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Sample records for 2-propenoic acid 2-methyl

  1. 40 CFR 721.10326 - 2-Propenoic acid, 2-methyl-, methyl ester, polymer with butyl 2-propenoate, ethyl 2-propenoate...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... ester, polymer with butyl 2-propenoate, ethyl 2-propenoate, zinc 2-methyl-2-propenoate (1:2) and zinc 2... 2-Propenoic acid, 2-methyl-, methyl ester, polymer with butyl 2-propenoate, ethyl 2-propenoate, zinc 2-methyl-2-propenoate (1:2) and zinc 2-propenoate (1:2), 2,2'-(1,2-diazenediyl)bis - and...

  2. 40 CFR 721.10326 - 2-Propenoic acid, 2-methyl-, methyl ester, polymer with butyl 2-propenoate, ethyl 2-propenoate...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... ester, polymer with butyl 2-propenoate, ethyl 2-propenoate, zinc 2-methyl-2-propenoate (1:2) and zinc 2...-propenoate, zinc 2-methyl-2-propenoate (1:2) and zinc 2-propenoate (1:2), 2,2′-(1,2-diazenediyl)bis - and 2,2... butyl 2-propenoate, ethyl 2-propenoate, zinc 2-methyl-2-propenoate (1:2) and zinc 2-propenoate (1:2),...

  3. 40 CFR 721.10326 - 2-Propenoic acid, 2-methyl-, methyl ester, polymer with butyl 2-propenoate, ethyl 2-propenoate...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... ester, polymer with butyl 2-propenoate, ethyl 2-propenoate, zinc 2-methyl-2-propenoate (1:2) and zinc 2...-propenoate, zinc 2-methyl-2-propenoate (1:2) and zinc 2-propenoate (1:2), 2,2′-(1,2-diazenediyl)bis - and 2,2... butyl 2-propenoate, ethyl 2-propenoate, zinc 2-methyl-2-propenoate (1:2) and zinc 2-propenoate (1:2),...

  4. 40 CFR 721.10133 - 2-Propenoic acid, 2-methyl, 2-hydroxyethyl ester, homopolymer.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...-hydroxyethyl ester, homopolymer. 721.10133 Section 721.10133 Protection of Environment ENVIRONMENTAL PROTECTION... New Uses for Specific Chemical Substances § 721.10133 2-Propenoic acid, 2-methyl, 2-hydroxyethyl ester... identified as 2-propenoic acid, 2-methyl, 2-hydroxyethyl ester, homopolymer (PMN P-07-401; CAS No....

  5. 40 CFR 721.10133 - 2-Propenoic acid, 2-methyl, 2-hydroxyethyl ester, homopolymer.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...-hydroxyethyl ester, homopolymer. 721.10133 Section 721.10133 Protection of Environment ENVIRONMENTAL PROTECTION... New Uses for Specific Chemical Substances § 721.10133 2-Propenoic acid, 2-methyl, 2-hydroxyethyl ester... identified as 2-propenoic acid, 2-methyl, 2-hydroxyethyl ester, homopolymer (PMN P-07-401; CAS No....

  6. 40 CFR 721.10136 - 2-Propenoic acid, 2-methyl-, 2-hydroxyethyl ester, reaction products with hexakis(alkoxyalkyl...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...-hydroxyethyl ester, reaction products with hexakis(alkoxyalkyl)melamine (generic). 721.10136 Section 721.10136... SIGNIFICANT NEW USES OF CHEMICAL SUBSTANCES Significant New Uses for Specific Chemical Substances § 721.10136 2-Propenoic acid, 2-methyl-, 2-hydroxyethyl ester, reaction products with...

  7. 40 CFR 721.10136 - 2-Propenoic acid, 2-methyl-, 2-hydroxyethyl ester, reaction products with hexakis(alkoxyalkyl...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...-hydroxyethyl ester, reaction products with hexakis(alkoxyalkyl)melamine (generic). 721.10136 Section 721.10136... SIGNIFICANT NEW USES OF CHEMICAL SUBSTANCES Significant New Uses for Specific Chemical Substances § 721.10136 2-Propenoic acid, 2-methyl-, 2-hydroxyethyl ester, reaction products with...

  8. 40 CFR 721.10136 - 2-Propenoic acid, 2-methyl-, 2-hydroxyethyl ester, reaction products with hexakis(alkoxyalkyl...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...-hydroxyethyl ester, reaction products with hexakis(alkoxyalkyl)melamine (generic). 721.10136 Section 721.10136... SIGNIFICANT NEW USES OF CHEMICAL SUBSTANCES Significant New Uses for Specific Chemical Substances § 721.10136 2-Propenoic acid, 2-methyl-, 2-hydroxyethyl ester, reaction products with...

  9. 40 CFR 721.10136 - 2-Propenoic acid, 2-methyl-, 2-hydroxyethyl ester, reaction products with hexakis(alkoxyalkyl...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...-hydroxyethyl ester, reaction products with hexakis(alkoxyalkyl)melamine (generic). 721.10136 Section 721.10136... SIGNIFICANT NEW USES OF CHEMICAL SUBSTANCES Significant New Uses for Specific Chemical Substances § 721.10136 2-Propenoic acid, 2-methyl-, 2-hydroxyethyl ester, reaction products with...

  10. 40 CFR 721.10136 - 2-Propenoic acid, 2-methyl-, 2-hydroxyethyl ester, reaction products with hexakis(alkoxyalkyl...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...-hydroxyethyl ester, reaction products with hexakis(alkoxyalkyl)melamine (generic). 721.10136 Section 721.10136... SIGNIFICANT NEW USES OF CHEMICAL SUBSTANCES Significant New Uses for Specific Chemical Substances § 721.10136 2-Propenoic acid, 2-methyl-, 2-hydroxyethyl ester, reaction products with...

  11. 40 CFR 721.4792 - 2-propenoic acid, 2-methyl-, C11-14-isoalkyl esters, C13-rich.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...-isoalkyl esters, C13-rich. 721.4792 Section 721.4792 Protection of Environment ENVIRONMENTAL PROTECTION... esters, C13-rich. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as 2-propenoic acid, 2-methyl-, C11-14-isoalkyl esters, C13-rich (PMN P-99-1189; CAS...

  12. 40 CFR 721.4792 - 2-propenoic acid, 2-methyl-, C11-14-isoalkyl esters, C13-rich.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...-isoalkyl esters, C13-rich. 721.4792 Section 721.4792 Protection of Environment ENVIRONMENTAL PROTECTION... esters, C13-rich. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as 2-propenoic acid, 2-methyl-, C11-14-isoalkyl esters, C13-rich (PMN P-99-1189; CAS...

  13. 75 FR 50926 - 2-propenoic acid, 2-methyl-, C12-16-alkyl esters, telomers with 1-dodecanethiol, polyethylene...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-08-18

    ...This regulation establishes an exemption from the requirement of a tolerance for residues of 2-propenoic acid, 2-methyl-, C12-16- alkyl esters, telomers with 1-dodecanethiol, polyethylene-polypropylene glycol ether with propylene glycol monomethacrylate (1:1), and styrene 2,2'-(1,2-diazenediyl)bis[2-methylbutanenitrile]-initiated, number average molecular weight (in AMU) 4000; when used as an......

  14. 40 CFR 721.10122 - 2-Propenoic acid, 2-methyl-, 1,1′-[2-ethyl-2-[[(2-methyl-1-oxo-2-propen-1-yl)oxy]methyl]- 1,3...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false 2-Propenoic acid, 2-methyl-, 1,1â²- methyl]- 1,3-propanediyl] ester, polymer with 1,3-butadiene, ethenylbenzene and 2-hydroxyethyl 2-methyl-2-propenoate. 721.10122 Section 721.10122 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) TOXIC SUBSTANCES CONTROL...

  15. 40 CFR 721.8450 - 2-Propenoic acid, 2-methyl-, 2-[3-(2H-benzotriazol-2-yl)-4-hydroxyphenyl]ethyl ester.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... ester. 721.8450 Section 721.8450 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED... Specific Chemical Substances § 721.8450 2-Propenoic acid, 2-methyl-, 2- ethyl ester. (a) Chemical substance... acid, 2-methyl-, 2- ethyl ester, (PMN P-90-333) is subject to reporting under this section for...

  16. 40 CFR 721.10526 - 2-Propenoic acid, 2-methyl-, 2-hydroxyethyl ester, telomers with C18-26-alkyl acrylate, 1...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false 2-Propenoic acid, 2-methyl-, 2-hydroxyethyl ester, telomers with C18-26-alkyl acrylate, 1-dodecanethiol, N-(hydroxymethyl)-2-methyl-2-propenamide, polyfluorooctyl methacrylate and vinylidene chloride, 2,2'- hydrochloride (1:2)-initiated (generic). 721.10526 Section 721.10526...

  17. 40 CFR 721.10526 - 2-Propenoic acid, 2-methyl-, 2-hydroxyethyl ester, telomers with C18-26-alkyl acrylate, 1...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false 2-Propenoic acid, 2-methyl-, 2-hydroxyethyl ester, telomers with C18-26-alkyl acrylate, 1-dodecanethiol, N-(hydroxymethyl)-2-methyl-2-propenamide, polyfluorooctyl methacrylate and vinylidene chloride, 2,2'- hydrochloride (1:2)-initiated (generic). 721.10526 Section 721.10526...

  18. 40 CFR 721.10122 - 2-Propenoic acid, 2-methyl-, 1,1′-[2-ethyl-2-[[(2-methyl-1-oxo-2-propen-1-yl)oxy]methyl]- 1,3...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...- methyl]- 1,3-propanediyl] ester, polymer with 1,3-butadiene, ethenylbenzene and 2-hydroxyethyl 2-methyl-2..., polymer with 1,3-butadiene, ethenylbenzene and 2-hydroxyethyl 2-methyl-2-propenoate. (a) Chemical...-propenoic acid, 2-methyl-, 1,1′- methyl]- 1,3-propanediyl] ester, polymer with 1,3-butadiene,...

  19. 40 CFR 721.10122 - 2-Propenoic acid, 2-methyl-, 1,1′-[2-ethyl-2-[[(2-methyl-1-oxo-2-propen-1-yl)oxy]methyl]- 1,3...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...- methyl]- 1,3-propanediyl] ester, polymer with 1,3-butadiene, ethenylbenzene and 2-hydroxyethyl 2-methyl-2..., polymer with 1,3-butadiene, ethenylbenzene and 2-hydroxyethyl 2-methyl-2-propenoate. (a) Chemical...-propenoic acid, 2-methyl-, 1,1′- methyl]- 1,3-propanediyl] ester, polymer with 1,3-butadiene,...

  20. 40 CFR 721.10122 - 2-Propenoic acid, 2-methyl-, 1,1′-[2-ethyl-2-[[(2-methyl-1-oxo-2-propen-1-yl)oxy]methyl]- 1,3...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...- methyl]- 1,3-propanediyl] ester, polymer with 1,3-butadiene, ethenylbenzene and 2-hydroxyethyl 2-methyl-2..., polymer with 1,3-butadiene, ethenylbenzene and 2-hydroxyethyl 2-methyl-2-propenoate. (a) Chemical...-propenoic acid, 2-methyl-, 1,1′- methyl]- 1,3-propanediyl] ester, polymer with 1,3-butadiene,...

  1. 40 CFR 721.10122 - 2-Propenoic acid, 2-methyl-, 1,1′-[2-ethyl-2-[[(2-methyl-1-oxo-2-propen-1-yl)oxy]methyl]- 1,3...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...- methyl]- 1,3-propanediyl] ester, polymer with 1,3-butadiene, ethenylbenzene and 2-hydroxyethyl 2-methyl-2..., polymer with 1,3-butadiene, ethenylbenzene and 2-hydroxyethyl 2-methyl-2-propenoate. (a) Chemical...-propenoic acid, 2-methyl-, 1,1′- methyl]- 1,3-propanediyl] ester, polymer with 1,3-butadiene,...

  2. 40 CFR 721.8450 - 2-Propenoic acid, 2-methyl-, 2-[3-(2H-benzotriazol-2-yl)-4-hydroxyphenyl]ethyl ester.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false 2-Propenoic acid, 2-methyl-, 2- ethyl ester. 721.8450 Section 721.8450 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) TOXIC SUBSTANCES CONTROL ACT SIGNIFICANT NEW USES OF CHEMICAL SUBSTANCES Significant New Uses...

  3. 40 CFR 721.8450 - 2-Propenoic acid, 2-methyl-, 2-[3-(2H-benzotriazol-2-yl)-4-hydroxyphenyl]ethyl ester.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false 2-Propenoic acid, 2-methyl-, 2- ethyl ester. 721.8450 Section 721.8450 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) TOXIC SUBSTANCES CONTROL ACT SIGNIFICANT NEW USES OF CHEMICAL SUBSTANCES Significant New Uses...

  4. 40 CFR 721.8450 - 2-Propenoic acid, 2-methyl-, 2-[3-(2H-benzotriazol-2-yl)-4-hydroxyphenyl]ethyl ester.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false 2-Propenoic acid, 2-methyl-, 2- ethyl ester. 721.8450 Section 721.8450 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) TOXIC SUBSTANCES CONTROL ACT SIGNIFICANT NEW USES OF CHEMICAL SUBSTANCES Significant New Uses...

  5. 40 CFR 721.8450 - 2-Propenoic acid, 2-methyl-, 2-[3-(2H-benzotriazol-2-yl)-4-hydroxyphenyl]ethyl ester.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false 2-Propenoic acid, 2-methyl-, 2- ethyl ester. 721.8450 Section 721.8450 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) TOXIC SUBSTANCES CONTROL ACT SIGNIFICANT NEW USES OF CHEMICAL SUBSTANCES Significant New Uses...

  6. 40 CFR 721.8340 - Mono esters from 2- propenoic acid (generic).

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Mono esters from 2- propenoic acid... Specific Chemical Substances § 721.8340 Mono esters from 2- propenoic acid (generic). (a) Chemical... as mono esters from 2-propenoic acid (PMN P-01-85) is subject to reporting under this section for...

  7. 40 CFR 721.8340 - Mono esters from 2- propenoic acid (generic).

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Mono esters from 2- propenoic acid... Specific Chemical Substances § 721.8340 Mono esters from 2- propenoic acid (generic). (a) Chemical... as mono esters from 2-propenoic acid (PMN P-01-85) is subject to reporting under this section for...

  8. 76 FR 41135 - 2-Propenoic acid, 2-methyl-, phenylmethyl ester, polymer with 2-propenoic acid and sodium 2...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-07-13

    ... Findings In the Federal Register of April 20, 2011 (76 FR 22069) (FRL-8869- 7), EPA issued a notice... Regulatory Planning and Review (58 FR 51735, October 4, 1993). Because this final rule has been exempted from... Actions Concerning Regulations That Significantly Affect Energy Supply, Distribution, or Use (66 FR...

  9. 40 CFR 721.8350 - 2-Propenoic acid, 7-oxa-bi-cy-clo[4.1.0]hept-3-ylmethyl ester.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false 2-Propenoic acid, 7-oxa-bi-cy-clo hept-3-ylmethyl ester. 721.8350 Section 721.8350 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) TOXIC SUBSTANCES CONTROL ACT SIGNIFICANT NEW USES OF CHEMICAL SUBSTANCES Significant New Uses for Specific Chemical Substances...

  10. Preparation and electrochemical properties of gel polymer electrolytes using triethylene glycol diacetate-2-propenoic acid butyl ester copolymer for high energy density lithium-ion batteries

    NASA Astrophysics Data System (ADS)

    Fan, Huanhuan; Li, Hongxiao; Fan, Li-Zhen; Shi, Qiao

    2014-03-01

    Gel polymer electrolytes (GPE) composed of triethylene glycol diacetate (TEGDA)-2-propenoic acid butyl ester (BA) copolymer and commercial used liquid organic electrolyte are prepared via in situ polymerization. The ionic conductivity of the as-prepared GPE can reach 5.5 × 10-3 S cm-1 with 6 wt% monomers and 94 wt% liquid electrolyte at 25 °C. Additionally, the temperature dependence of the ionic conductivity is consistent with an Arrhenius temperature behavior in a temperature range of 20-90 °C. Furthermore, the electrochemical stability window of the GPE is 5 V at 25 °C. A Li|GPE|(Li[Li1/6Ni1/4Mn7/12]O2) cell has been fabricated, which shows good charge-discharge properties and stable cycle performance compared to liquid electrolyte under the same test conditions.

  11. Effect of polyacrylonitrile on triethylene glycol diacetate-2-propenoic acid butyl ester gel polymer electrolytes with interpenetrating crosslinked network for flexible lithium ion batteries

    NASA Astrophysics Data System (ADS)

    Wang, Qiujun; Song, Wei-Li; Fan, Li-Zhen; Shi, Qiao

    2015-11-01

    A new flexible gel polymer electrolytes (GPE) with interpenetrating cross-linked network is fabricated by blending long-chain polyacrylonitrile (PAN) polymer matrix and short-chain triethylene glycol diacetate-2-propenoic acid butyl ester (TEGDA-BA) framework, with the purpose of enhancing the mechanical stability of the GPE frameworks via synergistic effects of the linear polymers and crosslinked monomers. The as fabricated frameworks enable the liquid electrolytes to be firmly entrapped in the polymeric matrices, which significantly improves the mechanical bendability and interface stability of the resultant GPE. The GPE with 5 wt% PAN exhibits high ionic conductivity up to 5.9 × 10-3 S cm-1 at 25 °C with a stable electrochemical window observed (>5.0 V vs. Li/Li+). The Li|GPE|LiFePO4 half cells demonstrate remarkably stable capacity retention and rate ability during cycling tests. As expected, the LiFePO4|GPE|Li4Ti5O12 full cells also exhibit discharge capacity of 125.2 mAh g-1 coupled with high columbic efficiency greater than 98% after 100 cycles. The excellent mechanical flexibility and charge/discharge performance suggest that the GPE holds great application potential in flexible LIBs.

  12. 40 CFR 721.8500 - 2-Propenoic acid, 2-methyl-, 7-oxabicyclo [4.1.0]hept-3-ylmethyl ester.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... § 721.63 (a)(1), (a)(3), (a)(4), (a)(5)(viii), (a)(5)(xv), (a)(6)(i), (a)(6)(ii), (a)(6)(iv), (b) (concentration set at 0.1 percent), and (c). (ii) Hazard communication program. Requirements as specified in... hept-3-ylmethyl ester. (a) Chemical substance and significant new uses subject to reporting. (1)...

  13. 40 CFR 721.8500 - 2-Propenoic acid, 2-methyl-, 7-oxabicyclo [4.1.0]hept-3-ylmethyl ester.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... § 721.63 (a)(1), (a)(3), (a)(4), (a)(5)(viii), (a)(5)(xv), (a)(6)(i), (a)(6)(ii), (a)(6)(iv), (b) (concentration set at 0.1 percent), and (c). (ii) Hazard communication program. Requirements as specified in... hept-3-ylmethyl ester. (a) Chemical substance and significant new uses subject to reporting. (1)...

  14. 77 FR 20314 - 2-Propenoic Acid, 2-Methyl-, 2-Ethylhexyl Ester, Telomer With 1-Dodecanethiol, Ethenylbenzene and...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-04-04

    ... Register of Friday, December 30, 2011 (76 FR 82238) (FRL-9331-1), EPA issued a notice pursuant to section... these rules from review under Executive Order 12866, entitled Regulatory Planning and Review (58 FR... That Significantly Affect Energy Supply, Distribution, or Use (66 FR 28355, May 22, 2001) or...

  15. 75 FR 4292 - 2-Propenoic acid, 2-ethylhexyl ester, polymer with ethenylbenzene and 2-methylpropyl 2-methyl-2...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-01-27

    ... Findings In the Federal Register of October 7, 2009 (74 FR 51597) (FRL-8792- 7), EPA issued a notice... Planning and Review (58 FR 51735, October 4, 1993). Because this final rule has been exempted from review... Concerning Regulations That Significantly Affect Energy Supply, Distribution, or Use (66 FR 28355, May...

  16. 2-Methyl-4-chlorophenoxyacetic acid (MCPA)

    Integrated Risk Information System (IRIS)

    2 - Methyl - 4 - chlorophenoxyacetic acid ( MCPA ) ; CASRN 94 - 74 - 6 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard

  17. 40 CFR 721.8485 - 2-Propenoic acid, 2-methyl-, (octahydro-4,7-methano-1H- indene-5-diyl)bis(methylene) ester.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...-, (octahydro-4,7-methano-1H- indene-5-diyl)bis(methylene) ester. 721.8485 Section 721.8485 Protection of...-methyl-, (octahydro-4,7-methano-1H- indene-5-diyl)bis(methylene) ester. (a) Chemical substance and...-, (octahydro-4,7-methano- 1H- indene-5-diyl)bis(methylene) ester (PMN P-99-1075; CAS No. 43048-08-4) is...

  18. 40 CFR 721.8485 - 2-Propenoic acid, 2-methyl-, (octahydro-4,7-methano-1H- indene-5-diyl)bis(methylene) ester.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...-, (octahydro-4,7-methano-1H- indene-5-diyl)bis(methylene) ester. 721.8485 Section 721.8485 Protection of...-methyl-, (octahydro-4,7-methano-1H- indene-5-diyl)bis(methylene) ester. (a) Chemical substance and...-, (octahydro-4,7-methano- 1H- indene-5-diyl)bis(methylene) ester (PMN P-99-1075; CAS No. 43048-08-4) is...

  19. 2-Methyl-aspartic acid monohydrate.

    PubMed

    Brewer, Greg; Burton, Aaron S; Dworkin, Jason P; Butcher, Ray J

    2013-11-30

    The title compound, C5H9NO4·H2O, is an isomer of the α-amino acid glutamic acid that crystallizes from water in its zwitterionic form as a monohydrate. It is not one of the 20 proteinogenic α-amino acids that are used in living systems and differs from the natural amino acids in that it has an α-methyl group rather than an α-H atom. In the crystal, an O-H⋯O hydrogen bond is present between the acid and water mol-ecules while extensive N-H⋯O and O-H⋯O hydrogen bonds link the components into a three-dimensional array. PMID:24454270

  20. 2-(2-Methyl-4-chlorophenoxy)propionic acid (MCPP)

    Integrated Risk Information System (IRIS)

    2 - ( 2 - Methyl - 4 - chlorophenoxy ) propionic acid ( MCPP ) ; CASRN 93 - 65 - 2 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( H

  1. 4-(2-Methyl-4-chlorophenoxy) butyric acid (MCPB)

    Integrated Risk Information System (IRIS)

    4 - ( 2 - Methyl - 4 - chlorophenoxy ) butyric acid ( MCPB ) ; CASRN 94 - 81 - 5 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Hea

  2. 40 CFR 180.318 - 4-(2-Methyl-4-chlorophenoxy) butyric acid; tolerance for residues.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...)butanoic acid, and its metabolite MCPA, (4-chloro-2-methylphenoxy)acetic acid, in or on the following food... acid; tolerance for residues. 180.318 Section 180.318 Protection of Environment ENVIRONMENTAL... FOOD Specific Tolerances § 180.318 4-(2-Methyl-4-chlorophenoxy) butyric acid; tolerance for...

  3. Aplastic anaemia after exposure to a weed killer, 2-methyl-4-chlorphenoxyacetic acid.

    PubMed

    Palva, H L; Koivisto, O; Palva, I P

    1975-01-01

    A 64-year-old farmer developed aplastic anaemia after exposure to 2-methyl-4-chlorphenoxyactic acid while spraying weed killer. Muscular weakness, haemorrhagic gastritis and slight signs of liver damage occurred at the same time. All these symptoms, including blood dyscrasia , are consistent with those described as toxic effects of chlorphenoxyacetic acids in animal experiments. A causal relationship between aplastic anaemia and the 2-methyl-4-chlorphenoxyacetic acid thus seems probable. The anaemia was reversible, but the case serves as a warning that careful safety measures are required during the use of chlorphenoxyacetic acids and related compounds. PMID:804793

  4. Acute leukaemia after exposure to a weed killer, 2-methyl-4-chlorphenoxyacetic acid.

    PubMed

    Timonen, T T; Palva, I P

    1980-01-01

    Acute leukaemia is known to develop in many cases of benzene-induced pancytopenia [1]. This is a report of the development of acute leukaemia in a patient who had apparently recovered from pancytopenia after chronic exposure to a weed killer, 2-methyl-4-chlorphenoxyacetic acid. PMID:6769284

  5. 40 CFR 721.9582 - Certain perfluoroalkyl sulfonates.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...-N-(hydroxyethyl), reaction products with 1,1′-methylenebis 70776-36-2 2-Propenoic acid, 2-methyl...- amino]ethyl 2-propenoate 127133-66-8 2-Propenoic acid, 2-methyl-, polymers with Bu methacrylate, lauryl...]ethyl esters 148684-79-1 Sulfonamides, C4-8-alkane, perfluoro, N-(hydroxyethyl)-N-methyl,...

  6. 40 CFR 721.9582 - Certain perfluoroalkyl sulfonates.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...-N-(hydroxyethyl), reaction products with 1,1′-methylenebis 70776-36-2 2-Propenoic acid, 2-methyl...- amino]ethyl 2-propenoate 127133-66-8 2-Propenoic acid, 2-methyl-, polymers with Bu methacrylate, lauryl...]ethyl esters 148684-79-1 Sulfonamides, C4-8-alkane, perfluoro, N-(hydroxyethyl)-N-methyl,...

  7. 40 CFR 721.9582 - Certain perfluoroalkyl sulfonates.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...-N-(hydroxyethyl), reaction products with 1,1′-methylenebis 70776-36-2 2-Propenoic acid, 2-methyl...- amino]ethyl 2-propenoate 127133-66-8 2-Propenoic acid, 2-methyl-, polymers with Bu methacrylate, lauryl...]ethyl esters 148684-79-1 Sulfonamides, C4-8-alkane, perfluoro, N-(hydroxyethyl)-N-methyl,...

  8. 40 CFR 721.10363 - Alkenoic acid, 2-methyl-, 2-oxiranylmethyl ester, reaction products with 4,4′ -methylenebis...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...-oxiranylmethyl ester, reaction products with 4,4â² -methylenebis (cyclohexanamine) (generic). 721.10363 Section... CONTROL ACT SIGNIFICANT NEW USES OF CHEMICAL SUBSTANCES Significant New Uses for Specific Chemical Substances § 721.10363 Alkenoic acid, 2-methyl-, 2-oxiranylmethyl ester, reaction products with...

  9. 40 CFR 721.10363 - Alkenoic acid, 2-methyl-, 2-oxiranylmethyl ester, reaction products with 4,4′ -methylenebis...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...-oxiranylmethyl ester, reaction products with 4,4â² -methylenebis (cyclohexanamine) (generic). 721.10363 Section... CONTROL ACT SIGNIFICANT NEW USES OF CHEMICAL SUBSTANCES Significant New Uses for Specific Chemical Substances § 721.10363 Alkenoic acid, 2-methyl-, 2-oxiranylmethyl ester, reaction products with...

  10. 40 CFR 721.10363 - Alkenoic acid, 2-methyl-, 2-oxiranylmethyl ester, reaction products with 4,4′ -methylenebis...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...-oxiranylmethyl ester, reaction products with 4,4â² -methylenebis (cyclohexanamine) (generic). 721.10363 Section... CONTROL ACT SIGNIFICANT NEW USES OF CHEMICAL SUBSTANCES Significant New Uses for Specific Chemical Substances § 721.10363 Alkenoic acid, 2-methyl-, 2-oxiranylmethyl ester, reaction products with...

  11. Selectivity of substrate binding and ionization of 2-methyl-3-hydroxypyridine-5-carboxylic acid oxygenase.

    PubMed

    Luanloet, Thikumporn; Sucharitakul, Jeerus; Chaiyen, Pimchai

    2015-08-01

    2-Methyl-3-hydroxypyridine-5-carboxylic acid (MHPC) oxygenase (EC 1.14.12.4) from Pseudomonas sp. MA-1 is a flavin-dependent monooxygenase that catalyzes a hydroxylation and aromatic ring cleavage reaction. The functional roles of two residues, Tyr223 and Tyr82, located ~ 5 Å away from MHPC, were characterized using site-directed mutagenesis, along with ligand binding, product analysis and transient kinetic experiments. Mutation of Tyr223 resulted in enzyme variants that were impaired in their hydroxylation activity and had Kd values for substrate binding 5-10-fold greater than the wild-type enzyme. Because this residue is adjacent to the water molecule that is located next to the 3-hydroxy group of MHPC, the results indicate that the interaction between Tyr223, H2 O and the 3-hydroxyl group of MHPC are important for substrate binding and hydroxylation. By contrast, the Kd for substrate binding of Tyr82His and Tyr82Phe variants were similar to that of the wild-type enzyme. However, only ~ 40-50% of the substrate was hydroxylated in the reactions of both variants, whereas most of the substrate was hydroxylated in the wild-type enzyme reaction. In free solution, MHPC or 5-hydroxynicotinic acid exists in a mixture of monoanionic and tripolar ionic forms, whereas only the tripolar ionic form binds to the wild-type enzyme. The binding of tripolar ionic MHPC would allow efficient hydroxylation through an electrophilic aromatic substitution mechanism. For the Tyr82His and Tyr82Phe variants, both forms of substrates can bind to the enzymes, indicating that the mutation at Tyr82 abolished the selectivity of the enzyme towards the tripolar ionic form. Transient kinetic studies indicated that the hydroxylation rate constants of both Tyr82 variants are approximately two- to 2.5-fold higher than that of the wild-type enzyme. Altogether, our findings suggest that Tyr82 is important for the binding selectivity of MHPC oxygenase towards the tripolar ionic species, whereas the

  12. 40 CFR 721.9582 - Certain perfluoroalkyl sulfonates.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...-methyl-, octadecyl ester, polymer with 1,1-dichloroethene, 2- methylamino]ethyl 2-propenoate, N...-propenoate and 2- amino]ethyl 2-propenoate 127133-66-8 2-Propenoic acid, 2-methyl-, polymers with Bu...-methyl, reaction products with 1,6-diisocyanatohexane homopolymer and ethylene glycol...

  13. 40 CFR 180.318 - 4-(2-Methyl-4-chlorophenoxy) butyric acid; tolerance for residues.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... established for the combined residues, free and conjugated, of the herbicide MCPB, 4-(4-chloro-2-methylphenoxy)butanoic acid, and its metabolite MCPA, (4-chloro-2-methylphenoxy)acetic acid, in or on the following...

  14. Vibrational spectra and natural bond orbital analysis of the herbicidal molecule 2(4-chlorophenoxy)-2-methyl propionic acid

    NASA Astrophysics Data System (ADS)

    Monicka, J. Clemy; James, C.

    2011-02-01

    The herbicide 2(4-chlorophenoxy)-2-methyl propionic acid (MCPP) has been subjected to NIR FT-Raman and infrared spectral studies. The optimized molecular structure, vibrational wavenumbers, IR intensities and Raman activities have been calculated by using density functional method (B3LYP) with the standard 6-31G(d) basis set. The calculated molecular geometry has been compared with the XRD data. The detailed assignments of the normal modes have been performed based on the potential energy distribution (PED) following the scaled quantum mechanical force field (SQMFF) methodology. The IR and Raman spectra have been plotted for the calculated wavenumbers. The simulated spectra satisfactorily coincide with the experimental spectra. The strong hyperconjugative interaction and charge delocalization that leads to the stability of the molecule have been investigated with the aid of natural bond orbital (NBO) analysis.

  15. An unusual case of non-fatal poisoning due to herbicide 4-chloro-2-methyl phenoxyacetic acid (MCPA).

    PubMed

    Tennakoon, D A S Sakunthala; Perera, K A P Bandumala; Hathurusinghe, L S

    2014-10-01

    MCPA (4-chloro-2-methyl phenoxyacetic acid) is a systemic hormone-type selective herbicide readily absorbed by leaves and roots. Use of MCPA for murder or attempted murder is very rare in Sri Lanka. However, a reported case of attempted murder by adding MCPA to water will be discussed in this paper. Three extraction methods were carried out with urine samples spiked with MCPA, namely liquid-liquid extraction with chloroform, solid phase extraction using C18 cartridges and vortex mixing with methanolic hydrochloric acid. Based on the recovery results, solid phase extraction was selected as the most suitable method and applied in the analysis of urine and water samples. Identification of MCPA in urine, water and the suspected poison bottle was carried out by HPLC and was confirmed by GC-MS. 4-chloro -2- methyl phenol metabolite was also identified and confirmed in the urine sample of the patient by GC-MS. Quantitative analysis of MCPA was carried out by HPLC using a validated method where Zorbax XDB-C18 column was used with photo diode array detector. In this case, presence of MCPA in one patient's urine sample collected four days after the incident was confirmed by GC-MS and found at a concentration of 0.83μg/ml. MCPA was not identified in the urine samples collected after 13 days in other three patients. The water sample taken from the suspected water storage tank found to contain 101μg/ml of MCPA. The results showed that HPLC combined with GC-MS is suitable for forensic analysis of MCPA in urine. PMID:24867053

  16. The use of poly(2-acrylamido-2-methyl-1-propanesulfonic acid) polymers as spacers for isotachophoresis in sieving gel matrices.

    PubMed

    Bellini, M P; Manchester, K L

    1999-03-01

    The electric field strength gradients generated in isotachophoresis (ITP) may be used for the separation of biomolecules. Poly(2-acrylamido-2-methyl-1-propanesulfonic acid) (polyAMPS) polymers of a uniform distribution of molecular mass were synthesized and used as novel spacers in ITP. Since these polymeric spacers are strongly acidic species, their ionic charges remain constant over a wide pH range, so that their ionic mobilities are governed solely by their molecular masses and not by the pH of the milieu. A modification of ITP known as telescope electrophoresis was used to separate a number of acidic dyes of varying ionic mobility, using polyAMPS polymers as spacers. The resolution obtained was superior to that obtained by polyacrylamide gel electrophoresis (PAGE), due to the focusing effect of the electric field strength gradient. Since these novel polymeric spacers are designed to operate within sieving medium, it was decided to test their suitability for the separation of DNA molecules. DNA molecules up to 1000 bp long were successfully resolved, with a similar resolution to that obtained with conventional PAGE. PMID:10036157

  17. Crystal structure of 3-acet-oxy-2-methyl-benzoic acid.

    PubMed

    Saranya, Matheswaran; Subashini, Annamalai; Arunagiri, Chidambaram; Muthiah, Packianathan Thomas

    2015-07-01

    In the title mol-ecule, C10H10O4, the carb-oxy-lic acid group is twisted by 11.37 (15)° from the plane of the benzene ring and the acet-oxy group is twisted from this plane by 86.60 (17)°. In the crystal, mol-ecules are linked by pairs of O-H⋯O hydrogen bonds, forming inversion dimers with the expected R 2 (2)(8) graph-set motif. PMID:26279915

  18. Crystal structure of (S)-2-amino-2-methyl­succinic acid

    PubMed Central

    Fujii, Isao

    2015-01-01

    The title compound, C5H9NO4, crystallized as a zwitterion. There is an intra­molecular N—H⋯O hydrogen bond involving the trans-succinic acid and the ammonium group, forming an S(6) ring motif. In the crystal, mol­ecules are linked by O—H⋯O hydrogen bonds, forming C(7) chains along the c-axis direction. The chains are linked by N—H⋯O and C—H⋯O hydrogen bonds, forming sheets parallel to the bc plane. Further N—H⋯O hydrogen bonds link the sheets to form a three-dimensional framework. PMID:26594447

  19. 1-Benzyl-2-methyl-3-indolylmethylene barbituric acid derivatives: Anti-cancer agents that target nucleophosmin 1 (NPM1).

    PubMed

    Penthala, Narsimha Reddy; Ketkar, Amit; Sekhar, Konjeti R; Freeman, Michael L; Eoff, Robert L; Balusu, Ramesh; Crooks, Peter A

    2015-11-15

    In the present study, we have designed and synthesized a series of 1-benzyl-2-methyl-3-indolylmethylene barbituric acid analogs (7a-7h) and 1-benzyl-2-methyl-3-indolylmethylene thiobarbituric acid analogs (7 i-7 l) as nucleophosmin 1 (NPM1) inhibitors and have evaluated them for their anti-cancer activity against a panel of 60 different human cancer cell lines. Among these analogs 7 i, 7 j, and 7 k demonstrated potent growth inhibitory effects in various cancer cell types with GI50 values <2 μM. Compound 7 k exhibited growth inhibitory effects on a sub-panel of six leukemia cell lines with GI50 values in the range 0.22-0.35 μM. Analog 7 i also exhibited GI50 values <0.35 μM against three of the leukemia cell lines in the sub-panel. Analogs 7 i, 7 j, 7 k and 7 l were also evaluated against the mutant NPM1 expressing OCI-AML3 cell line and compounds 7 k and 7 l were found to cause dose-dependent apoptosis (AP50 = 1.75 μM and 3.3 μM, respectively). Compound 7k also exhibited potent growth inhibition against a wide variety of solid tumor cell lines: that is, A498 renal cancer (GI50 = 0.19 μM), HOP-92 and NCI-H522 lung cancer (GI50 = 0.25 μM), COLO 205 and HCT-116 colon cancer (GI50 = 0.20 and 0.26 μM, respectively), CNS cancer SF-539 (GI50 = 0.22 μM), melanoma MDA-MB-435 (GI50 = 0.22 μM), and breast cancer HS 578T (GI50 = 0.22 μM) cell lines. Molecular docking studies suggest that compounds 7 k and 7 l exert their anti-leukemic activity by binding to a pocket in the central channel of the NPM1 pentameric structure. These results indicate that the small molecule inhibitors 7 i, 7 j, 7 k, and 7 l could be potentially developed into anti-NPM1 drugs for the treatment of a variety of hematologic malignancies and solid tumors. PMID:26602084

  20. First European Report of Social Wasps Trapped in Response to Acetic acid, Isobutanol, 2-Methyl-2-propanol, and Heptyl butyrate in Tests Conducted in Hungary

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Five species of social wasps were captured in trapping tests in Hungary that evaluated the attractiveness of acetic acid, isobutanol, 2-methyl-2-propanol, and heptyl butyrate to social wasps. Both Vespula vulgaris (L.) and Vespula germanica (Fabr.), were captured in traps baited with isobutanol, t...

  1. 21 CFR 73.3100 - 1,4-Bis[(2-hydroxyethyl)amino]-9,10-anthracenedione bis(2-propenoic)ester copolymers.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 1 2012-04-01 2012-04-01 false 1,4-Bis -9,10-anthracenedione bis(2-propenoic)ester copolymers. 73.3100 Section 73.3100 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES GENERAL LISTING OF COLOR ADDITIVES EXEMPT FROM CERTIFICATION Medical...

  2. 21 CFR 73.3100 - 1,4-Bis[(2-hydroxyethyl)amino]-9,10-anthracenedione bis(2-propenoic)ester copolymers.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 1 2013-04-01 2013-04-01 false 1,4-Bis -9,10-anthracenedione bis(2-propenoic)ester copolymers. 73.3100 Section 73.3100 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES GENERAL LISTING OF COLOR ADDITIVES EXEMPT FROM CERTIFICATION Medical...

  3. Structure of the PLP Degradative Enzyme 2-Methyl-3-hydroxypyridine-5-carboxylic Acid Oxygenase from Mesorhizobium loti MAFF303099 and Its Mechanistic Implications

    SciTech Connect

    McCulloch, Kathryn M.; Mukherjee, Tathagata; Begley, Tadhg P.; Ealick, Steven E.; Cornell

    2009-06-12

    A vitamin B{sub 6} degradative pathway has recently been identified and characterized in Mesorhizobium loti MAFF303099. One of the enzymes on this pathway, 2-methyl-3-hydroxypyridine-5-carboxylic acid oxygenase (MHPCO), is a flavin-dependent enzyme and catalyzes the oxidative ring-opening of 2-methyl-3-hydroxypyridine-5-carboxylic acid to form E-2-(acetamino-methylene)succinate. The gene for this enzyme has been cloned, and the corresponding protein has been overexpressed in Escherichia coli and purified. The crystal structure of MHPCO has been solved to 2.1 {angstrom} using SAD phasing with and without the substrate MHPC bound. These crystal structures provide insight into the reaction mechanism and suggest roles for active site residues in the catalysis of a novel oxidative ring-opening reaction.

  4. 40 CFR 721.10064 - 2-Propenoic acid, 2-[2-(ethenyloxy)ethoxy]ethyl ester.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... workplace. Requirements as specified in § 721.63 (a)(1), (a)(2)(i), (a)(3)(i), (b), and (c). North Butyl... permissible. (ii) Hazard communication program. Requirements as specified in § 721.72 (a), (b), (c), (d), (f...)(5). (iii) Industrial, commercial, and consumer activities. Requirements as specified in §...

  5. 40 CFR 721.10064 - 2-Propenoic acid, 2-[2-(ethenyloxy)ethoxy]ethyl ester.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... workplace. Requirements as specified in § 721.63 (a)(1), (a)(2)(i), (a)(3)(i), (b), and (c). North Butyl... permissible. (ii) Hazard communication program. Requirements as specified in § 721.72 (a), (b), (c), (d), (f...)(5). (iii) Industrial, commercial, and consumer activities. Requirements as specified in §...

  6. 75 FR 31713 - 2-Propenoic acid polymer, with 1,3-butadiene and ethenylbenzene; Tolerance Exemption

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-06-04

    ...) 305-5805. II. Background and Statutory Findings In the Federal Register of March 19, 2010 (75 FR 13277... Order 12866, entitled Regulatory Planning and Review (58 FR 51735, October 4, 1993). Because this final..., Distribution, or Use (66 FR 28355, May 22, 2001) or Executive Order 13045, entitled Protection of Children...

  7. 76 FR 52875 - 2-Propenoic Acid, Polymer With Ethenylbenzene and (1-methylethenyl) Benzene, Sodium Salt...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-08-24

    ... Findings In the Federal Register Wednesday, July 6, 2011 (76 FR 39358) (FRL- 8875-6), EPA issued a notice... FR 51735, October 4, 1993). Because this final rule has been exempted from review under Executive... Regulations That Significantly Affect Energy Supply, Distribution, or Use (66 FR 28355, May 22, 2001)...

  8. Evaluation of 2-methyl-3-hydroxy-4-pyridinecarboxylic acid as a possible chelating agent for iron and aluminium.

    PubMed

    Dean, Annalisa; Ferlin, Maria Grazia; Brun, Paola; Castagliuolo, Ignazio; Badocco, Denis; Pastore, Paolo; Venzo, Alfonso; Bombi, G Giorgio; Di Marco, Valerio B

    2008-04-01

    In view of a possible application to Fe and Al chelation therapy, 2-methyl-3-hydroxy-4-pyridinecarboxylic acid (DT2) was synthesised, and its complex formation, electrochemical and cytotoxic properties were studied. The complexing properties of DT2 towards Fe(III) and Al(III) were investigated in aqueous 0.6 m (Na)Cl at 25 degrees C by means of potentiometric titrations, UV-vis spectrophotometry, and 1H NMR spectroscopy. DT2 is a triprotic acid (H3L+) having pKa1 = 0.47, pKa2 = 5.64 and pKa3 = 11.18. The metal-ligand complexes observed in solution and their corresponding stability constants (log beta values) are the following: FeLH (19.38), FeL (16.01), FeLH(-1) (12.28), FeL2H2 (37.29), FeL3H3 (53.41), FeL3H2 (47.99), FeL3H (41.21) and FeL3 (34.1); AlLH (17.43), AlL2H2 (33.74), AlL2H (27.6), AlL3H3 (48.72), AlL3H2 (42.67), AlL3H (35.8) and AlL3 (27.92). The complex formation between DT2 and Fe(II) was studied by UV-vis: the weak complex FeLH (log beta = 15.8) was detected. DT2 shows a lower complexation efficiency with Fe(III) and Al(III) than that of other available chelators, but higher than that of its non-methylated analogue 3-hydroxy-4-pyridinecarboxylic acid (DT0). The electrochemical behaviour of DT2 was investigated by means of cyclic voltammetry, indicating that the oxidation of the ligand proceeds through a two electron process with a CECE mechanism. Voltammetric curves suggest that the oxidation or the reduction of DT2 in vivo is unlikely. According to the thermodynamic data, also the Fe(III)-DT2 complexes do not undergo redox cycling at physiological pH. Amperometric titrations of solutions containing Fe(III) and DT2 at pH = 5 indicated the same Fe(III) : ligand stoichiometric ratio as calculated from potentiometric data. The toxicity of DT2 and of other simple hydroxypyridinecarboxylic acids was investigated in vitro and no cytotoxic activity was observed (IC50 > 0.1 mM) on cancer cell lines and also on primary human cells, following a three day

  9. 21 CFR 73.3100 - 1,4-Bis[(2-hydroxyethyl)amino]-9,10-anthracenedione bis(2-methyl-2-propenoic)ester copolymers.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... vinyl and/or acrylic monomers to form the contact lens material. (b) Uses and restrictions. (1) The... the Federal Food, Drug, and Cosmetic Act (the act) with respect to the contact lens made from...

  10. SYNTHESIS AND IN VITRO CHARACTERIZATION OF HYDROXYPROPYL METHYLCELLULOSE-GRAFT-POLY (ACRYLIC ACID/2-ACRYLAMIDO-2-METHYL-1-PROPANESULFONIC ACID) POLYMERIC NETWORK FOR CONTROLLED RELEASE OF CAPTOPRIL.

    PubMed

    Furqan Muhammad, Iqbal; Mahmood, Ahmad; Aysha, Rashid

    2016-01-01

    A super-absorbent hydrogel was developed by crosslinking of 2-acrylamido-2-methyl-1-propanesulfonic acid (AMPS) and acrylic acid with hydroxypropyl methylcellulose (HPMC) for controlled release drug delivery of captopril, a well known antihypertensive drug. Acrylic acid and AMPS were polymerized and crosslinked with HPMC by free radical polymerization, a widely used chemical crosslinking method. N,N'-methylenebisacrylamide (MBA) and potassium persulfate (KPS) were added as cross-linker and initiator, respectively. The hydrogel formulation was loaded with captopril (as model drug). The concentration of captopril was monitored at 205 nm using UV spectrophotometer. Equilibrium swelling ratio was determined at pH 2, 4.5 and 7.4 to evaluate the pH responsiveness of the formed hydrogel. The super-absorbent hydrogels were evaluated by FTIR, SEM, XRD, and thermal analysis (DSC and TGA). The formation of new copolymeric network was determined by FTIR, XRD, TGA and DSC analysis. The hydrogel formulations with acrylic acid and AMPS ratio of 4: 1 and lower amounts of crosslinker had shown maximum swelling. Moreover, higher release rate of captopril was observed at pH 7.4 than at pH 2, because of more swelling capacity of copolymer with increasing pH of the aqueous medium. The present research work confirms the development of a stable hydrogel comprising of HPMC with acrylic acid and AMPS. The prepared hydrogels exhibited pH sensitive behav-ior. This superabsorbent composite prepared could be a successful drug carrier for treating hypertension. PMID:27008813

  11. 21 CFR 73.3100 - 1,4-Bis[(2-hydroxyethyl)amino]-9,10-anthracenedione bis(2-propenoic)ester copolymers.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 1 2010-04-01 2010-04-01 false 1,4-Bis -9,10-anthracenedione bis(2-propenoic)ester copolymers. 73.3100 Section 73.3100 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES GENERAL LISTING OF COLOR ADDITIVES EXEMPT FROM CERTIFICATION Medical Devices § 73.3100 1,4-Bis -9,10-anthracenedione...

  12. 2-Acrylamido-2-methyl-1-propanesulfonic Acid Grafted Poly(vinylidene fluoride-co-hexafluoropropylene)-Based Acid-/Oxidative-Resistant Cation Exchange for Membrane Electrolysis.

    PubMed

    Pandey, Ravi P; Das, Arindam K; Shahi, Vinod K

    2015-12-30

    For developing acid-/oxidative-resistant aliphatic-polymer-based cation-exchange membrane (CEM), macromolecular modification of poly(vinylidene fluoride-co-hexafluoropropylene) (PVDF-co-HFP) was carried out by controlled chemical grafting of 2-acrylamido-2-methyl-1-propanesulfonic acid (AMPS). To introduce the unsaturation suitable for chemical grafting, dehydrofluorination of commercially available PVDF-co-HFP was achieved under alkaline medium. Sulfonated copolymer (SCP) was prepared by the free radical copolymerization of dehydofluorinated PVDF-co-HFP (DHPVDF-co-HFP) and AMPS in the presence of free radical initiator. Prepared SCP-based CEMs were analyzed for their morphological characteristics, ion-exchange capacity (IEC), water uptake, conductivity, and stabilities (mechanical, chemical, and thermal) in comparison with state-of-art Nafion117 membrane. High bound water content avoids the membrane dehydration, and most optimal (SCP-1.33) membrane exhibited about ∼2.5-fold high bound water content in comparison with that of Nafion117 membrane. Bunsen reaction of iodine-sulfur (I-S) was successfully performed by direct-contact-mode membrane electrolysis in a two-compartment electrolytic cell using different SCP membranes. High current efficiency (83-99%) confirmed absence of any side reaction and 328.05 kJ mol-H2(-1) energy was required for to produce 1 mol of H2 by electrolytic cell with SCP-1.33 membrane. In spite of low conductivity for reported SCP membrane in comparison with that of Nafion117 membrane, SCP-1.33 membrane was assessed as suitable candidate for electrolysis because of its low-cost nature and excellent stabilities in highly acidic environment may be due to partial fluorinated segments in the membrane structure. PMID:26642107

  13. Experimental study of the removal of copper ions using hydrogels of xanthan, 2-acrylamido-2-methyl-1-propane sulfonic acid, montmorillonite: Kinetic and equilibrium study.

    PubMed

    Aflaki Jalali, Marzieh; Dadvand Koohi, Ahmad; Sheykhan, Mehdi

    2016-05-20

    In this paper, removal of copper ions from aqueous solution using novel xanthan gum (XG) hydrogel, xanthan gum-graft-2-acrylamido-2-methyl-1-propane sulfonic acid (XG-g-P(AMPS)) hydrogel and xanthan gum-graft-2-acrylamido-2-methyl-1-propane sulfonic acid/montmorillonite (XG-g-P(AMPS)/MMT) hydrogel composite were studied. The structure and morphologies of the xanthan-based hydrogels were characterized by Fourier transform infrared spectroscopy (FTIR) and scanning electron microscope (SEM). Adsorbents comprised a porous crosslink structure with side chains that carried carboxyl, hydroxyl and sulfonate. Maximum adsorption was observed in the pH=5.2, initial concentrations of Cu(2+)=321.8 mg/L, Temperature=45 °C, contact time=5 h with 0.2 g/50 mL of the hydrogels. Adsorption process was found to follow Langmuir isotherm model with maximum adsorption capacity of 24.57, 39.06 and 29.49 mg/g for the XG, XG-g-P(AMPS) and XG-g-P(AMPS)/MMT, respectively. Adsorption kinetics data fitted well with pseudo second order model. The negative ΔG° values and the positive ΔS° confirmed that the adsorption was a spontaneous process. The positive ΔH° values suggested that the adsorption was endothermic in nature. PMID:26917382

  14. 40 CFR 261.33 - Discarded commercial chemical products, off-specification species, container residues, and spill...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...-Propenenitrile U152 126-98-7 2-Propenenitrile, 2-methyl- (I,T) U008 79-10-7 2-Propenoic acid (I) U113 140-88-5 2...-10-7 2-Propenoic acid (I) U009 107-13-1 Acrylonitrile U009 107-13-1 2-Propenenitrile U010...

  15. 40 CFR 261.33 - Discarded commercial chemical products, off-specification species, container residues, and spill...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...-Propenenitrile U152 126-98-7 2-Propenenitrile, 2-methyl- (I,T) U008 79-10-7 2-Propenoic acid (I) U113 140-88-5 2...-10-7 2-Propenoic acid (I) U009 107-13-1 Acrylonitrile U009 107-13-1 2-Propenenitrile U010...

  16. 40 CFR 261.33 - Discarded commercial chemical products, off-specification species, container residues, and spill...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...-Propenenitrile U152 126-98-7 2-Propenenitrile, 2-methyl- (I,T) U008 79-10-7 2-Propenoic acid (I) U113 140-88-5 2...-10-7 2-Propenoic acid (I) U009 107-13-1 Acrylonitrile U009 107-13-1 2-Propenenitrile U010...

  17. 40 CFR 261.33 - Discarded commercial chemical products, off-specification species, container residues, and spill...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...-Propenenitrile U152 126-98-7 2-Propenenitrile, 2-methyl- (I,T) U008 79-10-7 2-Propenoic acid (I) U113 140-88-5 2...-10-7 2-Propenoic acid (I) U009 107-13-1 Acrylonitrile U009 107-13-1 2-Propenenitrile U010...

  18. Synthesis and antibacterial activity of thioglycolic amino acid derivatives and dipeptides containing the 2-methyl-3,4-dihydroquinazolin-4-one moiety.

    PubMed

    Atta, F M

    1994-11-01

    3-(2'-Chloroethyl)-2-methyl-3,4-dihydroquinazolin-4-one (I) was reacted with sodio (sodium thioglycolate) in dry dioxane and yielded compound II. By using thionyl chloride, this compound was converted to the corresponding acid chloride (III). The prepared acyl chloride (III) was allowed to interact with different alpha-amino acids such as Gly, L-Ala, L-B-Phe, DL-Asp, L-Glu, L-Thr and L-Val to give new amino acid derivatives (IVa-g). A selected C-terminal derivative of glycine (IVa) was converted into acid chloride (V). The acid chloride formed was reacted with L-Ala, L-B-Phe, DL-Asp, L-Glu, L-Thr and L-Val and yielded the new dipeptides VIa-f. The structures of the synthesized compounds were elucidated by elemental analysis and IR spectra. The prepared peptides were tested for their antimicrobial activities by comparison with tetra-cycline as a reference compound. PMID:7765582

  19. Novel opioid peptide derived antagonists containing (2S)-2-methyl-3-(2,6-dimethyl-4-carbamoylphenyl)propanoic acid [(2S)-Mdcp].

    PubMed

    Ghosh, Animesh; Luo, Jie; Liu, Chen; Weltrowska, Grazyna; Lemieux, Carole; Chung, Nga N; Lu, Yixin; Schiller, Peter W

    2008-09-25

    A synthesis of the novel tyrosine analogue (2 S)-2-methyl-3-(2,6-dimethyl-4-carbamoylphenyl)propanoic acid [(2 S)-Mdcp] (15) was developed. In (2 S)-Mdcp, the amino and hydroxyl groups of 2',6'-dimethyltyrosine are replaced by a methyl and a carbamoyl group, respectively, and its substitution for Tyr (1) in opioid agonist peptides resulted in compounds showing antagonism at all three opioid receptors. The cyclic peptide (2 S)-Mdcp-c[D-Cys-Gly-Phe(pNO 2)-D-Cys]NH 2 (1) was a potent and selective mu antagonist, whereas (2 S)-Mdcp-c[D-Pen-Gly-Phe(pF)-Pen]-Phe-OH (3) showed subnanomolar delta antagonist activity and extraordinary delta selectivity. PMID:18800771

  20. Novel Opioid Peptide Derived Antagonists Containing (2S)-2-Methyl-3-(2,6-dimethyl-4-carbamoylphenyl)propanoic Acid [(2S)-Mdcp

    PubMed Central

    Ghosh, Animesh; Luo, Jie; Liu, Chen; Weltrowska, Grazyna; Lemieux, Carole; Chung, Nga N.; Lu, Yixin; Schiller, Peter W.

    2009-01-01

    A synthesis of the novel tyrosine analogue (2S)-2-methyl-3-(2,6-dimethyl-4-carbamoylphenyl)propanoic acid [(2S)-Mdcp] (15) was developed. In (2S)-Mdcp the amino- and hydroxyl groups of 2',6'-dimethyltyrosine are replaced by a methyl- and a carbamoyl group, respectively, and its substitution for Tyr1 in opioid agonist peptides resulted in compounds showing antagonism at all three opioid receptors. The cyclic peptide (2S)-Mdcp-c[D-Cys-Gly-Phe(pNO2)-D-Cys]NH2 (1) was a potent and selective μ antagonist, whereas (2S)-Mdcp-c[D-Pen-Gly-Phe(pF)-Pen]-Phe-OH (3) showed subnanomolar δ antagonist activity and extraordinary δ selectivity. PMID:18800771

  1. Transformation of microcystins to 2-methyl-3-methoxy-4-phenylbutyric acid by room temperature ozone oxidation for rapid quantification of total microcystins.

    PubMed

    Zhang, L L; Yu, R P; Wang, L P; Wu, S F; Song, Q J

    2016-04-20

    Microcystins (MCs) are cyanobacterial hepatotoxins capable of accumulation into animal tissues. To determine the total microcystins in water, a novel analytical method, including ozonolysis, methylation of 2-methyl-3-methoxy-4-phenylbutyric acid (MMPB) with methylchloroformate (MCF) and gas chromatography mass spectrometry (GC-MS) detection was developed. The results show that MCs can be oxidized by ozone to produce MMPB at ambient temperature, proving ozonation is an effective, rapid and green method for the transformation of MCs to MMPB without secondary pollution. The oxidation conditions as well as the esterification process were optimized and, subsequently applied to analysis of environmental samples. The method shows wide linear range and high sensitivity with a detection limit of 0.34 μg L(-1). The established method was successfully applied to the analysis of microcystins in water samples. PMID:26975781

  2. Secondary Organic Aerosol Formation from 2-Methyl-3-Buten-2-ol Photooxidation: Evidence of Acid-Catalyzed Reactive Uptake of Epoxides

    SciTech Connect

    Zhang, Haofei; Zhang, Zhenfa; Cui, Tianqu; Lin, Ying-Hsuan; Bhathela, Neil A.; Ortega, John; Worton, David; Goldstein, Allen H.; Guenther, Alex B.; Jimenez, Jose L.; Gold, Avram; Surratt, Jason D.

    2014-04-08

    Secondary organic aerosol (SOA) formation from 2-methyl-3-buten-2-ol (MBO) photooxidation has recently been observed in both field and laboratory studies. Similar to isoprene, MBO-derived SOA increases with elevated aerosol acidity in the absence of nitric oxide; therefore, an epoxide intermediate, (3,3-dimethyloxiran-2-yl)methanol (MBO epoxide) was synthesized and tentatively proposed here to explain this enhancement. In the present study, the potential of the synthetic MBO epoxide to form SOA via reactive uptake was systematically examined. SOA was observed only in the presence of acidic aerosols. Major SOA constituents, 2,3-dihydroxyisopentanol (DHIP) and MBO-derived organosulfate isomers, were chemically characterized in both laboratory-generated SOA and in ambient fine aerosols collected from the BEACHON-RoMBAS field campaign during summer 2011, where MBO emissions are substantial. Our results support epoxides as potential products of MBO photooxidation leading to formation of atmospheric SOA and suggest that reactive uptake of epoxides may generally explain acid enhancement of SOA observed from other biogenic hydrocarbons.

  3. Effects of a salt of cholestyramine and 2-[4-(p-chlorobenzoyl)phenoxy]2-methyl propionic acid (alpha-1081) on biliary lipid secretion in rats.

    PubMed

    Aldini, R; Barbara, L; Benelli, A; Borzatta, V; Geminiani, S; Mascellani, G; Morselli, A; Roda, A; Roda, E

    1981-11-01

    1 Hypolipidaemic agents may increase biliary cholesterol in man, inducing a supersaturated bile. 2 To evaluate this possible side-effect, we have studied bile lipid secretion over a period of 8 h with intact enterohepatic circulation and 4 h with complete interruption in rats treated for two months with a salt of cholestyramine and 2-[4-(p-chlorobenzoyl)-phenoxy]2-methyl propionic acid (alpha-1081, 1.150 g/kg body wt., daily), cholestyramine (1.125 g/kg body wt. daily), procetofenic acid (25 mg/kg body wt. daily) and saline respectively (six rats for each group). 3 Cholesterol saturation index significantly (P less than 0.005) increased (from 0.21 +/- 0.01 to 0.39 +/- 0.09, mean +/- s.d.), in rats fed with procetofenic acid but it did not in alpha-1081- and cholestyramine-treated animals. 4 Procetofenic acid and, to a lesser extent, cholestyramine increased the bile flow. Procetofenic acid increased cholesterol secretion from 0.45 +/- 0.17 to 0.94 +/- 0.19 mumol kg-1 body wt. h-1 (mean +/- s.d.). 5 Cholestyramine increased both serum cholesterol and bile acid secretion from 0.45 +/- 0.17 to 0.68 +/- 0.10 and 25.8 +/- 9.48 to 39.96 +/- 6.68 mumol kg-1 body wt. h-1 respectively; alpha-1081, on the contrary, had no effect on bile lipid secretion. 6 These data suggest that alpha-1081 may be used as a new hypolipidaemic drug without any risk of increasing cholesterol in bile. PMID:6895340

  4. Effects of a salt of cholestyramine and 2-[4-(p-chlorobenzoyl)phenoxy]2-methyl propionic acid (alpha-1081) on biliary lipid secretion in rats.

    PubMed Central

    Aldini, R.; Barbara, L.; Benelli, A.; Borzatta, V.; Geminiani, S.; Mascellani, G.; Morselli, A.; Roda, A.; Roda, E.

    1981-01-01

    1 Hypolipidaemic agents may increase biliary cholesterol in man, inducing a supersaturated bile. 2 To evaluate this possible side-effect, we have studied bile lipid secretion over a period of 8 h with intact enterohepatic circulation and 4 h with complete interruption in rats treated for two months with a salt of cholestyramine and 2-[4-(p-chlorobenzoyl)-phenoxy]2-methyl propionic acid (alpha-1081, 1.150 g/kg body wt., daily), cholestyramine (1.125 g/kg body wt. daily), procetofenic acid (25 mg/kg body wt. daily) and saline respectively (six rats for each group). 3 Cholesterol saturation index significantly (P less than 0.005) increased (from 0.21 +/- 0.01 to 0.39 +/- 0.09, mean +/- s.d.), in rats fed with procetofenic acid but it did not in alpha-1081- and cholestyramine-treated animals. 4 Procetofenic acid and, to a lesser extent, cholestyramine increased the bile flow. Procetofenic acid increased cholesterol secretion from 0.45 +/- 0.17 to 0.94 +/- 0.19 mumol kg-1 body wt. h-1 (mean +/- s.d.). 5 Cholestyramine increased both serum cholesterol and bile acid secretion from 0.45 +/- 0.17 to 0.68 +/- 0.10 and 25.8 +/- 9.48 to 39.96 +/- 6.68 mumol kg-1 body wt. h-1 respectively; alpha-1081, on the contrary, had no effect on bile lipid secretion. 6 These data suggest that alpha-1081 may be used as a new hypolipidaemic drug without any risk of increasing cholesterol in bile. PMID:6895340

  5. Polyacrylamido-2-methyl-1-propane sulfonic acid-grafted-natural rubber as bio-adsorbent for heavy metal removal from aqueous standard solution and industrial wastewater.

    PubMed

    Phetphaisit, Chor Wayakron; Yuanyang, Siriwan; Chaiyasith, Wipharat Chuachuad

    2016-01-15

    Bio-adsorbent modified natural rubber (modified NR) was prepared, by placing the sulfonic acid functional group on the isoprene chain. This modification was carried out with the aim to prepare material capable to remove heavy metals from aqueous solution. The structures of modified NR materials were characterized by FT-IR and NMR spectroscopies. Thermal gravimetric analysis of modified NR showed that the initial degradation temperature of rubber decreases with increasing amount of polyacrylamido-2-methyl-1-propane sulfonic acid (PAMPS) in the structure. In addition, water uptake of the rubber based materials was studied as a function of time and content of PAMPS. The influence of the amount of PAMPS grafted onto NR, time, pH, concentration of metal ions, temperature, and regeneration were studied in terms of their influence on the adsorption of heavy metals (Pb(2+), Cd(2+) and Cu(2+)). The adsorption isotherms of Pb(2+) and Cd(2+) were fitted to the Freundlich isotherm model, while Cu(2+) was fitted to the Langmuir isotherm. However, the results from these two isotherms resulted in a similar behavior. The adsorption capacity of the modified NR for the various heavy metals was in the following order: Pb(2+)∼Cd(2+)>Cu(2+). The maximum adsorption capacities of Pb(2+), Cd(2+), and Cu(2+) were 272.7, 267.2, and 89.7 mg/g of modified rubber, respectively. Moreover, the modified natural rubber was used for the removal of metal ions in real samples of industrial effluents where the efficiency and regeneration were also investigated. PMID:26348149

  6. Characterization of potential NMDA and cholecystokinin antagonists. II. Lipophilicity studies on 2-methyl-4-oxo-3H-quinazoline-3-alkyl-carboxylic acid derivatives.

    PubMed

    Almási, J; Takács-Novák, K; Kökösi, J; Vámos, J

    1999-03-25

    The lipophilicity of 17 newly synthesized potential NMDA and cholecystokinin antagonist 2-methyl-4-oxo-3H-quinazoline-3-alkyl-carboxylic acid derivatives has been investigated. The apparent partition coefficients of two amphoteric compounds of overlapping protonation (Q1 and Q2) were determined by shake-flask method and converted into true log P values using the protonation microconstants. The difference between their lipophilicity expressed with the true partition coefficients was less, than it could be expected from the 2D structures and was explained with conformational preferences and formation of intramolecular interactions. Out of the other 15 monoprotic quinazolone compounds the lipophilicity of ten molecules (Q8-Q17, experimental set) was determined by TLC method with the help of a calibration set consisting of 12 standard molecules, five quinazolones (Q3-Q7) and seven pyrido[1,2-a]pyrimidines (PP1-PP7). In order to justify the suitability of pyrido-pyrimidines as standards for the chromatographic log P determination of quinazolones, first Q3-Q7 were examined by TLC and HPLC using PP1-PP7 for calibration. Data showed good agreement of results obtained by shake-flask and two different chromatographic methods indicating the similar chromatographic behavior of the two bicyclic systems and the relevance of PP1-PP7 to extend the calibration set of quinazolones. The obtained log P values proved mostly the expected structure-activity relationships. Some findings, however, have revealed specific partition behavior of the compounds providing useful information in the estimation of their pharmacokinetics, and these are discussed in the paper. PMID:10089287

  7. A multiphasic hollow fiber reactor for the whole-cell bioconversion of 2-methyl-1,3-propanediol to (r)-beta-hydroxyisobutyric acid.

    PubMed

    León, R; Prazeres, D M; Fernandes, P; Molinari, F; Cabral, J M

    2001-01-01

    This paper describes the bioconversion of 2-methyl-1,3-propanediol to (R)-beta-hydoxyisobutyric acid (HIBA) by Acetobacter ALEI in a hollow fiber membrane bioreaction system arrangement that allows the integration of three liquid phases: the aqueous bioconversion phase, the organic phase consisting of a solution of trioctyl phosphine oxide (TOPO) in isooctane, and the third phase consisting of a basic stripping solution that allows reextraction of HIBA from the organic phase. A comparison of HIBA mass transfer experiments was carried out in the membrane reactor with two and three phases for different pH and TOPO concentrations. The use of the three-phase arrangement allows the extraction of high quantities of HIBA from the aqueous medium (higher than 85%) independently of the pH, whereas in the two-phase system the percentage of HIBA extracted from the aqueous medium was lower, 42% in the best case, and strongly influenced by the pH. The percentage of the extractive agent TOPO in the organic phase influenced on the mass transfer rate in both bi- and triphasic arrangements. By simply integrating the re-extraction phase in the system it was possible to increase the extraction yield by 2-fold, reduce the amount of TOPO by 4-fold, and operate at the more favorable pH 4. A bioconversion experiment was done in these conditions (pH = 4, TOPO = 5%) to confirm the advantages of including the third stripping solution. Fed-batch operation of the triphasic membrane reactor was maintained for more than 20 h, reaching an HIBA concentration in the stripping solution of 29 g L(-)(1). PMID:11386867

  8. Use of 8-substituted-FAD analogues to investigate the hydroxylation mechanism of the flavoprotein 2-methyl-3-hydroxypyridine-5-carboxylic acid oxygenase.

    PubMed

    Chaiyen, Pimchai; Sucharitakul, Jeerus; Svasti, Jisnuson; Entsch, Barrie; Massey, Vincent; Ballou, David P

    2004-04-01

    2-Methyl-3-hydroxypyridine-5-carboxylic acid (MHPC) oxygenase (MHPCO) is a flavoprotein that catalyzes the oxygenation of MHPC to form alpha-(N-acetylaminomethylene)-succinic acid. Although formally similar to the oxygenation reactions catalyzed by phenol hydroxylases, MHPCO catalyzes the oxygenation of a pyridyl derivative rather than a simple phenol. Therefore, in this study, the mechanism of the reaction was investigated by replacing the natural cofactor FAD with FAD analogues having various substituents (-Cl, -CN, -NH(2), -OCH(3)) at the C8-position of the isoalloxazine. Thermodynamic and catalytic properties of the reconstituted enzyme were investigated and found to be similar to those of the native enzyme, validating that these FAD analogues are reasonable to be used as mechanistic probes. Dissociation constants for the binding of MHPC or the substrate analogue 5-hydroxynicotinate (5HN) to the reconstituted enzymes indicate that the reconstituted enzymes bind well with ligands. Redox potential values of the reconstituted enzymes were measured and found to be more positive than the values of free FAD analogues, which correlated well with the electronic effects of the 8-substituents. Studies of the reductive half-reaction of MHPCO have shown that the rates of flavin reduction by NADH could be described as a parabolic relationship with the redox potential values of the reconstituted enzymes, which is consistent with the Marcus electron transfer theory. Studies of the oxidative half-reaction of MHPCO revealed that the rate of hydroxylation depended upon the different analogues employed. The rate constants for the hydroxylation step correlated with the calculated pK(a) values of the 8-substituted C(4a)-hydroxyflavin intermediates, which are the leaving groups in the oxygen transfer step. It was observed that the rates of hydroxylation were greater when the pK(a) values of C(4a)-hydroxyflavins were lower. Although these results are not as dramatic as those from

  9. Photodynamics of potent antioxidants: ferulic and caffeic acids.

    PubMed

    Horbury, Michael D; Baker, Lewis A; Quan, Wen-Dong; Greenough, Simon E; Stavros, Vasilios G

    2016-07-14

    The dynamics of ferulic acid (3-(4-hydroxy-3-methoxyphenyl)-2-propenoic acid) and caffeic acid (3-(3,4-dihydroxyphenyl)-2-propenoic acid) in acetonitrile, dioxane and water at pH 2.2 following photoexcitation to the first excited singlet state are reported. These hydroxycinnamic acids display both strong ultraviolet absorption and potent antioxidant activity, making them promising sunscreen components. Ferulic and caffeic acids have previously been shown to undergo trans-cis photoisomerization via irradiation studies, yet time-resolved measurements were unable to observe formation of the cis-isomer. In the present study, we are able to observe the formation of the cis-isomer as well as provide timescales of relaxation following initial photoexcitation. PMID:27310931

  10. 40 CFR 721.8350 - 2-Propenoic acid, 7-oxa-bi-cy-clo[4.1.0]hept-3-ylmethyl ester.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... significant new uses are: (i) Protection in the workplace. Requirements as specified in § 721.63 (a)(1), (a)(3), (a)(4), (a)(5)(viii), (a)(5)(xv), (a)(6)(i), (a)(6)(ii), (a)(6)(iv), (b) (concentration set at 0.1... ester. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical...

  11. 40 CFR 721.10218 - 2-Propenoic acid, 2-mehtyl-, C12-15-branched and linear alkyl esters, telomers with alkyl 2...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...-branched and linear alkyl esters, telomers with alkyl 2- thio]-2-alkanoate, aminoalkyl methacrylate and alkyl methacrylate, tert-Bu 2-ethylhexanoperoxoate-initiated (generic). 721.10218 Section 721.10218...-alkanoate, aminoalkyl methacrylate and alkyl methacrylate, tert-Bu 2-ethylhexanoperoxoate-initiated...

  12. 40 CFR 721.10218 - 2-Propenoic acid, 2-mehtyl-, C12-15-branched and linear alkyl esters, telomers with alkyl 2...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...-branched and linear alkyl esters, telomers with alkyl 2- thio]-2-alkanoate, aminoalkyl methacrylate and alkyl methacrylate, tert-Bu 2-ethylhexanoperoxoate-initiated (generic). 721.10218 Section 721.10218...-alkanoate, aminoalkyl methacrylate and alkyl methacrylate, tert-Bu 2-ethylhexanoperoxoate-initiated...

  13. 40 CFR 721.10218 - 2-Propenoic acid, 2-mehtyl-, C12-15-branched and linear alkyl esters, telomers with alkyl 2...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...-branched and linear alkyl esters, telomers with alkyl 2- thio]-2-alkanoate, aminoalkyl methacrylate and alkyl methacrylate, tert-Bu 2-ethylhexanoperoxoate-initiated (generic). 721.10218 Section 721.10218...-alkanoate, aminoalkyl methacrylate and alkyl methacrylate, tert-Bu 2-ethylhexanoperoxoate-initiated...

  14. 40 CFR 721.10218 - 2-Propenoic acid, 2-mehtyl-, C12-15-branched and linear alkyl esters, telomers with alkyl 2...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...-branched and linear alkyl esters, telomers with alkyl 2- thio]-2-alkanoate, aminoalkyl methacrylate and alkyl methacrylate, tert-Bu 2-ethylhexanoperoxoate-initiated (generic). 721.10218 Section 721.10218...-alkanoate, aminoalkyl methacrylate and alkyl methacrylate, tert-Bu 2-ethylhexanoperoxoate-initiated...

  15. Greening Wittig Reactions: Solvent-Free Synthesis of Ethyl Trans-Cinnamate and Trans-3-(9-Anthryl)-2-Propenoic Acid Ethyl Ester

    ERIC Educational Resources Information Center

    Nguyen, Kim Chi; Weizman, Haim

    2007-01-01

    Green procedure is used to create solvent-free alternatives for conventional Wittig reactions, which are widely used to install a double bond in a highly selective manner. Solvent-free reactions reduce health and environmental risks and provide a basis for an inquiry-based discussion of the stereochemistry of the Wittig reaction and the factors…

  16. Two-dimensional hydrogen-bonded polymers in the crystal structures of the ammonium salts of phen­oxy­acetic acid, (4-fluoro­phen­oxy)acetic acid and (4-chloro-2-methyl­phen­oxy)acetic acid

    PubMed Central

    Smith, Graham

    2014-01-01

    The structures of the ammonium salts of phen­oxy­acetic acid, NH4 +·C8H6O3 −, (I), (4-fluoro­phen­oxy)acetic acid, NH4 +·C8H5FO3 −, (II), and the herbicidally active (4-chloro-2-methyl­phen­oxy)acetic acid (MCPA), NH4 +·C9H8ClO3 −·0.5H2O, (III) have been determined. All have two-dimensional layered structures based on inter-species ammonium N—H⋯O hydrogen-bonding associations, which give core substructures consisting primarily of conjoined cyclic motifs. The crystals of (I) and (II) are isomorphous with the core comprising R 1 2(5), R 1 2(4) and centrosymmetric R 4 2(8) ring motifs, giving two-dimensional layers lying parallel to (100). In (III), the water mol­ecule of solvation lies on a crystallographic twofold rotation axis and bridges two carboxyl O atoms in an R 4 4(12) hydrogen-bonded motif, creating two R 4 3(10) rings, which together with a conjoined centrosymmetric R 4 2(8) ring incorporating both ammonium cations, generate two-dimensional layers lying parallel to (100). No π–π ring associations are present in any of the structures. PMID:25552984

  17. 40 CFR 721.1025 - Benzenamine, 4-chloro-2-methyl-; benzenamine, 4-chloro-2-methyl-, hydrochloride; and ben-zenamine...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Benzenamine, 4-chloro-2-methyl-; benzenamine, 4-chloro-2-methyl-, hydrochloride; and ben-zenamine, 2-chloro-6-methyl-. 721.1025 Section 721... Benzenamine, 4-chloro-2-methyl-; benzenamine, 4-chloro-2-methyl-, hydrochloride; and ben-zenamine,...

  18. 40 CFR 721.1025 - Benzenamine, 4-chloro-2-methyl-; benzenamine, 4-chloro-2-methyl-, hydrochloride; and ben-zenamine...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Benzenamine, 4-chloro-2-methyl-; benzenamine, 4-chloro-2-methyl-, hydrochloride; and ben-zenamine, 2-chloro-6-methyl-. 721.1025 Section 721... Benzenamine, 4-chloro-2-methyl-; benzenamine, 4-chloro-2-methyl-, hydrochloride; and ben-zenamine,...

  19. Synthesis, Radiolabeling and Biological Evaluation of (R)- and (S)-2-Amino-3-[18F]Fluoro-2-Methylpropanoic Acid (FAMP) and (R)- and (S)-3-[18F]Fluoro-2-Methyl-2-N-(Methylamino)propanoic Acid (NMeFAMP) as Potential PET Radioligands for Imaging Brain Tumors

    PubMed Central

    Yu, Weiping; McConathy, Jonathan; Williams, Larry; Camp, Vernon M.; Malveaux, Eugene J.; Zhang, Zhaobin; Olson, Jeffrey J.; Goodman, Mark M.

    2009-01-01

    The non-natural amino acids (R)- and (S)-2-amino-3-fluoro-2-methylpropanoic acid 5 and (R)- and (S)-3-fluoro-2-methyl-2-N-(methylamino)propanoic acid 8 were synthesized in shorter reaction sequences than in the original report starting from enantiomerically pure (S)- and (R)-α-methyl-serine, respectively. The reaction sequence provided the cyclic sulfamidate precursors for radiosynthesis of (R)- and (S)-[18F]5 and (R)- and (S)-[18F]8 in fewer steps than in the original report. (R)- and (S)-[18F]5 and(R)- and (S)-[18F]8 were synthesized by no-carrier-added nucleophilic [18F]fluorination in 52–66% decay-corrected-yields with radiochemical purity over 99%. The cell assays showed that all four compounds were substrates for amino acid transport and enter 9L rat gliosarcoma cells in vitro at least in part by system-A amino acid transport. The biodistribution studies demonstrated that in vivo tumor to normal brain ratios for all compounds were high with ratios of 20:1 to115:1 in rats with intracranial 9L tumors. The (R)- enantiomers of [18F]5 and [18F]8 demonstrated higher tumor uptake in vivo compared to the (S)- enantiomers. PMID:20028004

  20. 40 CFR 261.33 - Discarded commercial chemical products, off-specification species, container residues, and spill...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...-Propenenitrile U152 126-98-7 2-Propenenitrile, 2-methyl- (I,T) U008 79-10-7 2-Propenoic acid (I) U113 140-88-5 2... Acrylonitrile U009 107-13-1 2-Propenenitrile U010 50-07-7 Azirino pyrrolo indole-4,7-dione, 6-amino-8-...

  1. Dehydration of 2-Methyl-1-Cyclohexanol: New Findings from a Popular Undergraduate Laboratory Experiment

    ERIC Educational Resources Information Center

    Friesen, J. Brent; Schretzman, Robert

    2011-01-01

    The mineral acid-catalyzed dehydration of 2-methyl-1-cyclohexanol has been a popular laboratory exercise in second-year organic chemistry for several decades. The dehydration experiment is often performed by organic chemistry students to illustrate Zaitsev's rule. However, sensitive analytical techniques reveal that the results do not entirely…

  2. Pharmacological profile of novel acid pump antagonist 7-(4-fluorobenzyloxy)-2,3-dimethyl-1-{[(1S,2S)-2-methyl cyclopropyl]methyl}-1H-pyrrolo[2,3-d]pyridazine (CS-526).

    PubMed

    Ito, Keiichi; Kinoshita, Kazuya; Tomizawa, Atsuyuki; Inaba, Fumi; Morikawa-Inomata, Yuka; Makino, Mitsuko; Tabata, Keiichi; Shibakawa, Nobuhiko

    2007-10-01

    The pharmacological profiles of the novel acid pump antagonist 7-(4-fluorobenzyloxy)-2,3-dimethyl-1-{[(1S,2S)-2-methylcyclopropyl]methyl}-1H-pyrrolo[2,3-d]pyridazine (CS-526) were investigated in terms of hog gastric H+,K+-ATPase activity, gastric acid secretion, and acute gastroesophageal lesions in comparison with other proton pump inhibitors (PPIs). CS-526 inhibited H+,K+-ATPase activity in a concentration-dependent manner, with an IC50 value of 61 nM. The inhibitory effect of CS-526 on H+,K+-ATPase activity was more potent than that of any of the other PPIs examined. The inhibitory mechanism of CS-526 on H+,K+-ATPase was a competitive antagonism to the K+ binding site of H+,K+-ATPase, and it was also a reversible inhibition. In pylorus-ligated rats, intraduodenal or oral administration of CS-526 inhibited gastric acid secretion in a dose-dependent manner, and the ID50 values were 2.8 or 0.7 mg/kg, respectively. In Heidenhain pouch dogs, intrapouch administration of CS-526 inhibited histamine-stimulated gastric acid secretion in a dose- and retention time-dependent manner. In a reflux esophagitis model, intraduodenal and oral administration of CS-526 prevented esophageal lesions with ID50 values of 5.4 and 1.9 mg/kg, respectively. Lansoprazole prevented esophagitis only by intraduodenal administration (ID50 = 2.2 mg/kg). Furthermore, CS-526 inhibited acute gastric mucosal lesions. These data demonstrate that the novel acid pump antagonist CS-526 has potent antisecretory and antiulcer effects. These findings indicate that CS-526 would have a curative effect on gastroesophageal reflux disease via its potent antisecretory and antiulcer actions. PMID:17630360

  3. A 2:1 co-crystal of 2-methyl­benzoic acid and N,N′-bis­(pyridin-4-ylmeth­yl)ethanedi­amide: crystal structure and Hirshfeld surface analysis

    PubMed Central

    Syed, Sabrina; Jotani, Mukesh M.; Halim, Siti Nadiah Abdul; Tiekink, Edward R. T.

    2016-01-01

    The asymmetric unit of the title 2:1 co-crystal, 2C8H8O2·C14H14N4O2, comprises an acid mol­ecule in a general position and half a di­amide mol­ecule, the latter being located about a centre of inversion. In the acid, the carb­oxy­lic acid group is twisted out of the plane of the benzene ring to which it is attached [dihedral angle = 28.51 (8)°] and the carbonyl O atom and methyl group lie approximately to the same side of the mol­ecule [hy­droxy-O—C—C—C(H) torsion angle = −27.92 (17)°]. In the di­amide, the central C4N2O2 core is almost planar (r.m.s. deviation = 0.031 Å), and the pyridyl rings are perpendicular, lying to either side of the central plane [central residue/pyridyl dihedral angle = 88.60 (5)°]. In the mol­ecular packing, three-mol­ecule aggregates are formed via hy­droxy-O—H⋯N(pyrid­yl) hydrogen bonds. These are connected into a supra­molecular layer parallel to (12) via amide-N—H⋯O(carbon­yl) hydrogen bonds, as well as methyl­ene-C—H⋯O(amide) inter­actions. Significant π–π inter­actions occur between benzene/benzene, pyrid­yl/benzene and pyrid­yl/pyridyl rings within and between layers to consolidate the three-dimensional packing. PMID:27006815

  4. A 2:1 co-crystal of 2-methyl-benzoic acid and N,N'-bis-(pyridin-4-ylmeth-yl)ethanedi-amide: crystal structure and Hirshfeld surface analysis.

    PubMed

    Syed, Sabrina; Jotani, Mukesh M; Halim, Siti Nadiah Abdul; Tiekink, Edward R T

    2016-03-01

    The asymmetric unit of the title 2:1 co-crystal, 2C8H8O2·C14H14N4O2, comprises an acid mol-ecule in a general position and half a di-amide mol-ecule, the latter being located about a centre of inversion. In the acid, the carb-oxy-lic acid group is twisted out of the plane of the benzene ring to which it is attached [dihedral angle = 28.51 (8)°] and the carbonyl O atom and methyl group lie approximately to the same side of the mol-ecule [hy-droxy-O-C-C-C(H) torsion angle = -27.92 (17)°]. In the di-amide, the central C4N2O2 core is almost planar (r.m.s. deviation = 0.031 Å), and the pyridyl rings are perpendicular, lying to either side of the central plane [central residue/pyridyl dihedral angle = 88.60 (5)°]. In the mol-ecular packing, three-mol-ecule aggregates are formed via hy-droxy-O-H⋯N(pyrid-yl) hydrogen bonds. These are connected into a supra-molecular layer parallel to (12[Formula: see text]) via amide-N-H⋯O(carbon-yl) hydrogen bonds, as well as methyl-ene-C-H⋯O(amide) inter-actions. Significant π-π inter-actions occur between benzene/benzene, pyrid-yl/benzene and pyrid-yl/pyridyl rings within and between layers to consolidate the three-dimensional packing. PMID:27006815

  5. Crystal structures of the two salts 2-methyl-1H-imidazol-3-ium nitrate–2-methyl-1H-imidazole (1/1) and 2-methyl-1H-imidazol-3-ium nitrate

    PubMed Central

    Diop, Mouhamadou Birame; Diop, Libasse; Maris, Thierry

    2016-01-01

    The title salts, C4H7N2 +·NO3 −·C4H6N2, (I), and C4H7N2 +·NO3 −, (II), were obtained from solutions containing 2-methyl­imidazole and nitric acid in different concentrations. In the crystal structure of salt (I), one of the –NH H atoms of the imidazole ring shows half-occupancy, hence only every second mol­ecule is in its cationic form. The nitrate anion in this structure lies on a twofold rotation axis. The neutral 2-methyl­imidazole mol­ecule and the 2-methyl-1H-imidazol-3-ium cation inter­act through N—H⋯N hydrogen bonds to form [(C4H6N2)⋯(C4H7N2)+] pairs. These pairs are linked with two nitrate anions on both sides through bifurcated N—H⋯(O,O) hydrogen bonds into chains running parallel to [001]. In the crystal structure of salt (II), the C4H7N2 + cation and the NO3 − anion are both located on a mirror plane, leading to a statistical disorder of the methyl H atoms. The cations and anions again inter­act through bifurcated N—H⋯(O,O) hydrogen bonds, giving rise to the formation of chains consisting of alternating anions and cations parallel to [100]. PMID:27375869

  6. Crystal structures of the two salts 2-methyl-1H-imidazol-3-ium nitrate-2-methyl-1H-imidazole (1/1) and 2-methyl-1H-imidazol-3-ium nitrate.

    PubMed

    Diop, Mouhamadou Birame; Diop, Libasse; Maris, Thierry

    2016-04-01

    The title salts, C4H7N2 (+)·NO3 (-)·C4H6N2, (I), and C4H7N2 (+)·NO3 (-), (II), were obtained from solutions containing 2-methyl-imidazole and nitric acid in different concentrations. In the crystal structure of salt (I), one of the -NH H atoms of the imidazole ring shows half-occupancy, hence only every second mol-ecule is in its cationic form. The nitrate anion in this structure lies on a twofold rotation axis. The neutral 2-methyl-imidazole mol-ecule and the 2-methyl-1H-imidazol-3-ium cation inter-act through N-H⋯N hydrogen bonds to form [(C4H6N2)⋯(C4H7N2)(+)] pairs. These pairs are linked with two nitrate anions on both sides through bifurcated N-H⋯(O,O) hydrogen bonds into chains running parallel to [001]. In the crystal structure of salt (II), the C4H7N2 (+) cation and the NO3 (-) anion are both located on a mirror plane, leading to a statistical disorder of the methyl H atoms. The cations and anions again inter-act through bifurcated N-H⋯(O,O) hydrogen bonds, giving rise to the formation of chains consisting of alternating anions and cations parallel to [100]. PMID:27375869

  7. Production of 2-methyl-1-butanol in engineered Escherichia coli.

    PubMed

    Cann, Anthony F; Liao, James C

    2008-11-01

    Recent progress has been made in the production of higher alcohols by harnessing the power of natural amino acid biosynthetic pathways. Here, we describe the first strain of Escherichia coli developed to produce the higher alcohol and potential new biofuel 2-methyl-1-butanol (2MB). To accomplish this, we explored the biodiversity of enzymes catalyzing key parts of the isoleucine biosynthetic pathway, finding that AHAS II (ilvGM) from Salmonella typhimurium and threonine deaminase (ilvA) from Corynebacterium glutamicum improve 2MB production the most. Overexpression of the native threonine biosynthetic operon (thrABC) on plasmid without the native transcription regulation also improved 2MB production in E. coli. Finally, we knocked out competing pathways upstream of threonine production (DeltametA, Deltatdh) to increase its availability for further improvement of 2MB production. This work led to a strain of E. coli that produces 1.25 g/L 2MB in 24 h, a total alcohol content of 3 g/L, and with yields of up to 0.17 g 2MB/g glucose. PMID:18758769

  8. Identification of a novel selective peroxisome proliferator-activated receptor alpha agonist, 2-methyl-2-(4-{3-[1-(4-methylbenzyl)-5-oxo-4,5-dihydro-1H-1,2,4-triazol-3-yl]propyl}phenoxy)propanoic acid (LY518674), that produces marked changes in serum lipids and apolipoprotein A-1 expression.

    PubMed

    Singh, Jai Pal; Kauffman, Raymond; Bensch, William; Wang, Guoming; McClelland, Pam; Bean, James; Montrose, Chahrzad; Mantlo, Nathan; Wagle, Asavari

    2005-09-01

    Low high-density lipoprotein-cholesterol (HDL-c) is an important risk factor of coronary artery disease (CAD). Optimum therapy for raising HDL-c is still not available. Identification of novel HDL-raising agents would produce a major impact on CAD. In this study, we have identified a potent (IC50 approximately 24 nM) and selective peroxisome proliferator-activated receptor alpha (PPARalpha) agonist, 2-methyl-2-(4-{3-[1-(4-methylbenzyl)-5-oxo-4,5-dihydro-1H-1,2,4-triazol-3-yl]propyl}phenoxy)propanoic acid (LY518674). In human apolipoprotein A-1 (apoA-1) transgenic mice, LY518674 produced a dose-dependent increase in serum HDL-c, resulting in 208 +/- 15% elevation at optimum dose. A new synthesis of apoA-1 contributed to the increase in HDL-c. LY518674 increased apoA-1 mRNA levels in liver. Moreover, liver slices from animals treated with LY518674 secreted 3- to 6-fold more apoA-1 than control liver slices. In cultured hepatocytes, LY518674 produced 50% higher apoA-1 secretion, which was associated with increase in radiolabeled methionine incorporation in apoA-1. Thus, LY518674 is a potent and selective PPARalpha agonist that produced a much greater increase in serum HDL-c than the known fibrate drugs. The increase in HDL-c was associated with de novo synthesis of apoA-1. PMID:15933217

  9. Palladium-catalysed direct C-2 methylation of indoles.

    PubMed

    Tu, Daoquan; Cheng, Xiuzhi; Gao, Yadong; Yang, Panpan; Ding, Yousong; Jiang, Chao

    2016-08-21

    A direct C-2 methylation reaction of indoles bearing a readily removable N-2-pyrimidyl moiety as a site-specific directing group has been developed with a palladium catalyst. This reaction relied on the use of KF to promote efficient methylation. A moderate to good yield was achieved in a range of indole substrates. PMID:27424955

  10. Solubility of nitrous oxide in aqueous blends of N-methyldiethanolamine and 2-amino-2-methyl-1-propanol

    SciTech Connect

    Davis, R.A.; Pogainis, B.J.

    1995-11-01

    Aqueous solutions of alkanolamines have applications in acid gas treatment for the removal of acid gases such as carbon dioxide and hydrogen sulfide. The solubility of nitrous oxide in aqueous blends of N-methyldiethanolamine and 2-amino-2-methyl-1 propanol was measured over the temperature range 10--60 C. The total composition of the alkanolamines in water ranged from 30 to 50 mass %. The experimental results were interpreted in terms of Henry`s constants.

  11. Crystal structure of 2-methyl-1H-imidazol-3-ium hydrogen oxalate dihydrate.

    PubMed

    Diop, Mouhamadou Birame; Diop, Libasse; Plasseraud, Laurent; Cattey, Hélène

    2016-08-01

    Single crystals of the title mol-ecular salt, C4H7N2 (+)·HC2O4 (-)·2H2O, were isolated from the reaction of 2-methyl-1H-imidazole and oxalic acid in a 1:1 molar ratio in water. In the crystal, the cations and anions are positioned alternately along an infinite [010] ribbon and linked together through bifurcated N-H⋯(O,O) hydrogen bonds. The water mol-ecules of crystallization link the chains into (10-1) bilayers, with the methyl groups of the cations organized in an isotactic manner. PMID:27536393

  12. Crystal structure of 2-methyl-1H-imidazol-3-ium hydrogen oxalate dihydrate

    PubMed Central

    Diop, Mouhamadou Birame; Diop, Libasse; Plasseraud, Laurent; Cattey, Hélène

    2016-01-01

    Single crystals of the title mol­ecular salt, C4H7N2 +·HC2O4 −·2H2O, were isolated from the reaction of 2-methyl-1H-imidazole and oxalic acid in a 1:1 molar ratio in water. In the crystal, the cations and anions are positioned alternately along an infinite [010] ribbon and linked together through bifurcated N—H⋯(O,O) hydrogen bonds. The water mol­ecules of crystallization link the chains into (10-1) bilayers, with the methyl groups of the cations organized in an isotactic manner. PMID:27536393

  13. Fragrance material review on 2-methyl-4-phenyl-2-butanol.

    PubMed

    Scognamiglio, J; Jones, L; Letizia, C S; Api, A M

    2012-09-01

    A toxicologic and dermatologic review of 2-methyl-4-phenyl-2-butanol when used as a fragrance ingredient is presented. 2-methyl-4-phenyl-2-butanol is a member of the fragrance structural group Aryl Alkyl Alcohols and is a tertiary alcohol. The AAAs are a structurally diverse class of fragrance ingredients that includes primary, secondary, and tertiary alkyl alcohols covalently bonded to an aryl (Ar) group, which may be either a substituted or unsubstituted benzene ring. The common structural element for the AAA fragrance ingredients is an alcohol group -C-(R1)(R2)OH and generically the AAA fragrances can be represented as an Ar-C-(R1)(R2)OH or Ar-Alkyl-C-(R1)(R2)OH group. This review contains a detailed summary of all available toxicology and dermatology papers that are related to this individual fragrance ingredient and is not intended as a stand-alone document. Available data for 2-methyl-4-phenyl-2-butanol were evaluated then summarized and includes physical properties, acute toxicity, skin irritation, and skin sensitization data. A safety assessment of the entire Aryl Alkyl Alcohols will be published simultaneously with this document; please refer to Belsito et al. (2012) for an overall assessment of the safe use of this material and all Aryl Alkyl Alcohols in fragrances. assessment of aryl alkyl alcohols when used as fragrance ingredients. PMID:22036982

  14. Fragrance material review on 2-methyl-5-phenylpentanol.

    PubMed

    Scognamiglio, J; Jones, L; Letizia, C S; Api, A M

    2012-09-01

    A toxicologic and dermatologic review of 2-methyl-5-phenylpentanol when used as a fragrance ingredient is presented. 2-Methyl-5-phenylpentanol is a member of the fragrance structural group aryl alkyl alcohols and is a primary alcohol. The AAAs are a structurally diverse class of fragrance ingredients that includes primary, secondary, and tertiary alkyl alcohols covalently bonded to an aryl (Ar) group, which may be either a substituted or unsubstituted benzene ring. The common structural element for the AAA fragrance ingredients is an alcohol group -C-(R1)(R2)OH and generically the AAA fragrances can be represented as an Ar-C-(R1)(R2)OH or Ar-Alkyl-C-(R1)(R2)OH group. This review contains a detailed summary of all available toxicology and dermatology papers that are related to this individual fragrance ingredient and is not intended as a stand-alone document. Available data for 2-methyl-5-phenylpentanol were evaluated then summarized and includes physical properties, acute toxicity, skin irritation, mucous membrane (eye) irritation, skin sensitization, repeated dose, and genotoxicity data. A safety assessment of the entire aryl alkyl alcohols will be published simultaneously with this document; please refer to Belsito et al. (2012) for an overall assessment of the safe use of this material and all other branched chain saturated alcohols in fragrances. PMID:22033092

  15. Fragrance material review on 2-methyl-4-phenylpentanol.

    PubMed

    Scognamiglio, J; Jones, L; Letizia, C S; Api, A M

    2012-09-01

    A toxicologic and dermatologic review of 2-methyl-4-phenylpentanol when used as a fragrance ingredient is presented. 2-Methyl-4-phenylpentanol is a member of the fragrance structural group Aryl Alkyl Alcohols and is a primary alcohol. The AAAs are a structurally diverse class of fragrance ingredients that includes primary, secondary, and tertiary alkyl alcohols covalently bonded to an aryl (Ar) group, which may be either a substituted or unsubstituted benzene ring. The common structural element for the AAA fragrance ingredients is an alcohol group -C-(R1)(R2)OH and generically the AAAs fragrances can be represented as an Ar-C-(R1)(R2)OH or Ar-Alkyl-C-(R1)(R2)OH group. This review contains a detailed summary of all available toxicology and dermatology papers that are related to this individual fragrance ingredient and is not intended as a stand-alone document. Available data for 2-methyl-4-phenylpentanol were evaluated then summarized and includes physical properties, acute toxicity, skin irritation, mucous membrane (eye) irritation, skin sensitization, repeated dose, and genotoxicity data. A safety assessment of the entire Aryl Alkyl Alcohols will be published simultaneously with this document; please refer to Belsito et al. (2012) for an overall assessment of the safe use of this material and all Aryl Alkyl Alcohols in fragrances. PMID:22036976

  16. Environmental analysis of the life cycle emissions of 2-methyl tetrahydrofuran solvent manufactured from renewable resources.

    PubMed

    Slater, C Stewart; Savelski, Mariano J; Hitchcock, David; Cavanagh, Eduardo J

    2016-01-01

    An environmental analysis has been conducted to determine the cradle to gate life cycle emissions to manufacture the green solvent, 2-methyl tetrahydrofuran. The solvent is considered a greener chemical since it can be manufactured from renewable resources with a lower life cycle footprint. Analyses have been performed using different methods to show greenness in both its production and industrial use. This solvent can potentially be substituted for other ether and chlorinated solvents commonly used in organometallic and biphasic reactions steps in pharmaceutical and fine chemical syntheses. The 2-methyl tetrahydrofuran made from renewable agricultural by-products is marketed by Penn A Kem under the name ecoMeTHF™. The starting material, 2-furfuraldehyde (furfural), is produced from corn cob waste by converting the available pentosans by acid hydrolysis. An evaluation of each step in the process was necessary to determine the overall life cycle and specific CO2 emissions for each raw material/intermediate produced. Allocation of credits for CO2 from the incineration of solvents made from renewable feedstocks significantly reduced the overall carbon footprint. Using this approach, the overall life cycle emissions for production of 1 kg of ecoMeTHF™ were determined to be 0.191 kg, including 0.150 kg of CO2. Life cycle emissions generated from raw material manufacture represents the majority of the overall environmental impact. Our evaluation shows that using 2-methyl tetrahydrofuran in an industrial scenario results in a 97% reduction in emissions, when compared to typically used solvents such as tetrahydrofuran, made through a conventional chemical route. PMID:26889729

  17. [Synthesis of 2-methyl-5-substituted phenoxy-primaquine and antimalarials activity].

    PubMed

    Zhong, B H; Deng, R X; Zhong, J X; Wang, J

    1990-01-01

    In searching for efficient, safe and radically curative agent and causal prophylactics for malaria, seven 2-methyl-5-substituted phenoxy-6-methoxy-8-(1-methyl-4-aminobutylamino)-quinolines (II1-7) were synthesized and their antimalarial activities were compared with the corresponding 4-methyl substituted derivatives of primaquine. The starting material, 2-nitro-4-methoxy-5-bromo-acetanilide (III), was prepared from p-methoxy aniline through acetylation, bromination and nitration. III was then condensed with substituted phenols in the presence of potassium carbonate. The condensed products were subsequently hydrolyzed with dilute alcoholic hydrochloric acid to yield 2-nitro-4-methoxy-5-substituted phenoxy-aniline (V) which underwent Skraup's reaction with 2-butenal to provide the key intermediates 2-methyl-5-substituted phenoxy-6-methoxy-8-nitroquinolines (VI). These 8-nitroquinoline derivatives were reduced to 8-aminoquinoline derivatives (VII). The latter were condensed with 4-bromo-1-phthalimido-pentane and then hydrolyzed with hydrazine hydrate, the final products were obtained as oxalate or succinate. The structure of the target compounds and unknown intermediates were confirmed by elementary and spectral analysis. Primary biological evaluation showed that all compounds II1-7 were much less active than the 4-methyl substituted derivatives and slightly less active than primaquine in both causal prophylactic test against Plasmodium yoelii and suppressive antimalarial test against P. berhei. PMID:2239331

  18. Spectrophotometric, Fourier transform infrared spectroscopic and theoretical studies of the charge-transfer complexes between methyldopa [(S)-2 amino-3-(3,4-dihydroxyphenyl)-2-methyl propanoic acid] and the acceptors (chloranilic acid, o-chloranil and dichlorodicyanobenzoquinone) in acetonitrile and their thermodynamic properties

    NASA Astrophysics Data System (ADS)

    Sharma, K.; Sharma, S. P.; Lahiri, S. C.

    Methyldopa is a much used antihypertensive drug. It is the subject matter of study mostly for the determination and estimation of methyldopa in pharmaceutical properties. These considerations led us to study the charge-transfer interactions between methyldopa, a centrally acting antihypertensive agent of limited use with the known acceptors like o-chloranil (o-ClN), chloranilic acid (ClA) and dichlorodicyanobenzoquinone (DDQ). Methyldopa (MDP) formed beautifully colored complexes (having absorption maxima at 581 nm and 368 nm; 519 nm; 583.5 nm, 547 nm and 346 nm, respectively) with the acceptors mentioned before. The physico-chemical properties of the complexes were studied using UV-visible spectrophotometry and FTIR measurements. The composition, the accurate association constants and thermodynamics of the complexes were determined spectrophotometrically. Attempts were made to interpret the thermodynamics of complexes in terms of IDV, EAV and hνCT. Solid CT complexes between MDP + o-ClN, MDP + ClA and MDP + DDQ were prepared and FTIR spectra of the complexes were studied. The energies hνCT of the charge-transfer complexes and vertical ionization potential IDV of methyldopa were compared with the theoretical values of hνCT obtained from HOMO and LUMO of the donors and acceptors calculated using Density Function Theory utilizing different basis sets. The agreement between the results can be regarded to be reasonable. Oscillator strengths and dipole strengths of the complexes were determined theoretically and experimentally and the limitations of the calculations were outlined.

  19. Spectrophotometric, Fourier transform infrared spectroscopic and theoretical studies of the charge-transfer complexes between methyldopa [(S)-2 amino-3-(3,4-dihydroxyphenyl)-2-methyl propanoic acid] and the acceptors (chloranilic acid, o-chloranil and dichlorodicyanobenzoquinone) in acetonitrile and their thermodynamic properties.

    PubMed

    Sharma, K; Sharma, S P; Lahiri, S C

    2012-06-15

    Methyldopa is a much used antihypertensive drug. It is the subject matter of study mostly for the determination and estimation of methyldopa in pharmaceutical properties. These considerations led us to study the charge-transfer interactions between methyldopa, a centrally acting antihypertensive agent of limited use with the known acceptors like o-chloranil (o-ClN), chloranilic acid (ClA) and dichlorodicyanobenzoquinone (DDQ). Methyldopa (MDP) formed beautifully colored complexes (having absorption maxima at 581 nm and 368 nm; 519 nm; 583.5 nm, 547 nm and 346 nm, respectively) with the acceptors mentioned before. The physico-chemical properties of the complexes were studied using UV-visible spectrophotometry and FTIR measurements. The composition, the accurate association constants and thermodynamics of the complexes were determined spectrophotometrically. Attempts were made to interpret the thermodynamics of complexes in terms of I(D)(V), E(A)(V) and hν(CT). Solid CT complexes between MDP+o-ClN, MDP+ClA and MDP+DDQ were prepared and FTIR spectra of the complexes were studied. The energies hν(CT) of the charge-transfer complexes and vertical ionization potential I(D)(V) of methyldopa were compared with the theoretical values of hν(CT) obtained from HOMO and LUMO of the donors and acceptors calculated using Density Function Theory utilizing different basis sets. The agreement between the results can be regarded to be reasonable. Oscillator strengths and dipole strengths of the complexes were determined theoretically and experimentally and the limitations of the calculations were outlined. PMID:22446770

  20. Enantioselective syntheses and sensory properties of 2-methyl-tetrahydrofuran-3-thiol acetates.

    PubMed

    Dai, Yifeng; Shao, Junqiang; Yang, Shaoxiang; Sun, Baoguo; Liu, Yongguo; Ning, Ting; Tian, Hongyu

    2015-01-21

    The enantioselective synthesis of four stereoisomers of 2-methyl-tetrahydrofuran-3-thiol acetate was achieved. The two enantiomers of the important intermediate cis-2-methyl-3-hydroxy-tetrahydrofuran were obtained by Sharpless asymmetric dihydroxylation (AD), whereas the two enantiomers of trans-2-methyl-3-hydroxy-tetrahydrofuran were derived from the corresponding optically active cis-isomers by Mitsunobu reaction. Each stereoisomer of 2-methyl-3-hydroxy-tetrahydrofuran went through mesylation and nucleophilic substitution to afford the corresponding product with specific configuration. (2R,3S)- and (2R,3R)-2-methyl-tetrahydrofuran-3-thiol acetate were obtained in 80% ee, whereas the (2S,3R)- and (2S,3S)-isomers were in 62% ee. The odor properties of the synthesized four stereoisomers were evaluated by gas chromatography-olfactometry (GC-O), which revealed perceptible differences among stereoisomers both in odor features and in intensities. PMID:25560460

  1. Excess molar enthalpies of ternary mixtures for propanone or benzene + aniline + 2-methyl-1-propanol and of binary mixtures for propanone or aniline + 2-methyl-1-propanol at 298.15 K

    SciTech Connect

    Nagata, Isamu; Tamura, Kazuhiro; Miyai, Koichi

    1996-11-01

    Experimental excess molar enthalpies for the ternary mixtures 2-methyl-1-propanol + aniline + propanone and 2-methyl-1-propanol + aniline + benzene and their constituent binary mixtures 2-methyl-1-propanol + aniline and 2-methyl-1-propanol + propanone at the temperature 298.15 K, measured by using an isothermal dilution calorimeter, are reported. The results have been analyzed using a polynomial equation and the UNIQUAC-associated solution model with binary and ternary parameters.

  2. Mutagenic activity associated with cooling tower waters treated with a biocide containing 5-chloro-2-methyl-4-isothiazolin-3-one

    SciTech Connect

    Woodall, G.M.; Pancorbo, O.C.; Blevins, R.D.; Ferslew, K.E.

    1987-08-01

    With the Ames Salmonella-mammalian microsome test, significant mutagenic activity was detected in cooling tower water shortly (same day) after treatment with a biocide (CL2150) containing 5-chloro-2-methyl-4-isothiazolin-3-one(5-chloro-IT). Dose-related mutagenic responses with TA97 (-S9) and TA100 (-S9) were produced with the acid fraction (extracted at pH <2 with methylene chloride) of this cooling water sample (specific mutagenic activities of 281,000 and 188,000 net revertants/L equiv of water, respectively). This mutagenic activity detected in cooling water sampled in mid-summer did not persist beyond the first day of CL2150 treatment. The mutagenic activity displayed by the cooling waters with TA97 (-S9) exceeded that associated with the extractable 5-chloro-IT concentration (determined by capillary gas chromatography-mass spectrometry). 24 references, 6 figures, 3 tables.

  3. UNIFAC parameters for maleic anhydride and 2-methyl furan in p-dioxane system

    SciTech Connect

    Daumn, K.J.

    1983-01-01

    The purpose of this work was to develop a method for calculating equilibrium concentrations for reversible liquid phase reactions from a minimum of experimental data. The example reaction studied was the Diels Alder reaction between 2-methyl furan and maleic anhydride. Specifically, interaction parameters of the UNIFAC model for groups in the compounds 2-methyl furan, maleic anhydride and the solvent, p-dioxane, were determined. The activity coefficient of each substance was then predicted by the UNIFAC method. Equilibrium constants at 45/sup 0/C for the Diels Alder reaction between 2-methyl furan and maleic anhydride were then calculated from these activity coefficients and two previously determined sets of equilibrium concentrations at 45/sup 0/C. These two equilibrium constants were within 12% of each other, which demonstrated the validity of the method.

  4. Biodegradation-inspired bioproduction of methylacetoin and 2-methyl-2,3-butanediol

    PubMed Central

    Jiang, Xinglin; Zhang, Haibo; Yang, Jianming; Zheng, Yanning; Feng, Dexin; Liu, Wei; Xu, Xin; Cao, Yujin; Zou, Huibin; Zhang, Rubin; Cheng, Tao; Jiao, Fengjiao; Xian, Mo

    2013-01-01

    Methylacetoin (3-hydroxy-3-methylbutan-2-one) and 2-methyl-2,3-butanediol are currently obtained exclusively via chemical synthesis. Here, we report, to the best of our knowledge, the first alternative route, using engineered Escherichia coli. The biological synthesis of methylacetoin was first accomplished by reversing its biodegradation, which involved modifying the enzyme complex involved, switching the reaction substrate, and coupling the process to an exothermic reaction. 2-Methyl-2,3-butanediol was then obtained by reducing methylacetoin by exploiting the substrate promiscuity of acetoin reductase. A complete biosynthetic pathway from renewable glucose and acetone was then established and optimized via in vivo enzyme screening and host metabolic engineering, which led to titers of 3.4 and 3.2 g l−1 for methylacetoin and 2-methyl-2,3-butanediol, respectively. This work presents a biodegradation-inspired approach to creating new biosynthetic pathways for small molecules with no available natural biosynthetic pathway. PMID:23945710

  5. Organosulfates as Tracers for Secondary Organic Aerosol (SOA) Formation from 2-Methyl-3-Buten-2-ol (MBO) in the Atmosphere

    PubMed Central

    2012-01-01

    2-Methyl-3-buten-2-ol (MBO) is an important biogenic volatile organic compound (BVOC) emitted by pine trees and a potential precursor of atmospheric secondary organic aerosol (SOA) in forested regions. In the present study, hydroxyl radical (OH)-initiated oxidation of MBO was examined in smog chambers under varied initial nitric oxide (NO) and aerosol acidity levels. Results indicate measurable SOA from MBO under low-NO conditions. Moreover, increasing aerosol acidity was found to enhance MBO SOA. Chemical characterization of laboratory-generated MBO SOA reveals that an organosulfate species (C5H12O6S, MW 200) formed and was substantially enhanced with elevated aerosol acidity. Ambient fine aerosol (PM2.5) samples collected from the BEARPEX campaign during 2007 and 2009, as well as from the BEACHON-RoMBAS campaign during 2011, were also analyzed. The MBO-derived organosulfate characterized from laboratory-generated aerosol was observed in PM2.5 collected from these campaigns, demonstrating that it is a molecular tracer for MBO-initiated SOA in the atmosphere. Furthermore, mass concentrations of the MBO-derived organosulfate are well correlated with MBO mixing ratio, temperature, and acidity in the field campaigns. Importantly, this compound accounted for an average of 0.25% and as high as 1% of the total organic aerosol mass during BEARPEX 2009. An epoxide intermediate generated under low-NO conditions is tentatively proposed to produce MBO SOA. PMID:22849588

  6. 40 CFR 721.9500 - Silane, (1,1-dimethylethoxy) dimethoxy(2-methyl propyl)-.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Silane, (1,1-dimethylethoxy) dimethoxy... New Uses for Specific Chemical Substances § 721.9500 Silane, (1,1-dimethylethoxy) dimethoxy(2-methyl... substance silane, (1,1-dimethylethoxy) dimethoxy (2-methylpropyl)- (PMN P-89-906) is subject to...

  7. 40 CFR 721.9500 - Silane, (1,1-dimethylethoxy) dimethoxy(2-methyl propyl)-.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Silane, (1,1-dimethylethoxy) dimethoxy... New Uses for Specific Chemical Substances § 721.9500 Silane, (1,1-dimethylethoxy) dimethoxy(2-methyl... substance silane, (1,1-dimethylethoxy) dimethoxy (2-methylpropyl)- (PMN P-89-906) is subject to...

  8. 40 CFR 721.9500 - Silane, (1,1-dimethylethoxy) dimethoxy(2-methyl propyl)-.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Silane, (1,1-dimethylethoxy) dimethoxy... New Uses for Specific Chemical Substances § 721.9500 Silane, (1,1-dimethylethoxy) dimethoxy(2-methyl... substance silane, (1,1-dimethylethoxy) dimethoxy (2-methylpropyl)- (PMN P-89-906) is subject to...

  9. 40 CFR 721.9500 - Silane, (1,1-dimethylethoxy) dimethoxy(2-methyl propyl)-.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Silane, (1,1-dimethylethoxy) dimethoxy... New Uses for Specific Chemical Substances § 721.9500 Silane, (1,1-dimethylethoxy) dimethoxy(2-methyl... substance silane, (1,1-dimethylethoxy) dimethoxy (2-methylpropyl)- (PMN P-89-906) is subject to...

  10. 40 CFR 721.9500 - Silane, (1,1-dimethylethoxy) dimethoxy(2-methyl propyl)-.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Silane, (1,1-dimethylethoxy) dimethoxy... New Uses for Specific Chemical Substances § 721.9500 Silane, (1,1-dimethylethoxy) dimethoxy(2-methyl... substance silane, (1,1-dimethylethoxy) dimethoxy (2-methylpropyl)- (PMN P-89-906) is subject to...

  11. 40 CFR 721.10049 - Phenol, 4,4′- cyclohexylidene bis[2-methyl-.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Phenol, 4,4â²- cyclohexylidene bis[2... Specific Chemical Substances § 721.10049 Phenol, 4,4′- cyclohexylidene bis[2-methyl-. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as a...

  12. 40 CFR 721.10049 - Phenol, 4,4′- cyclohexylidene bis[2-methyl-.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Phenol, 4,4â²- cyclohexylidene bis[2... Specific Chemical Substances § 721.10049 Phenol, 4,4′- cyclohexylidene bis[2-methyl-. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as a...

  13. 40 CFR 721.10049 - Phenol, 4,4′- cyclohexylidene bis[2-methyl-.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Phenol, 4,4â²- cyclohexylidene bis[2... Specific Chemical Substances § 721.10049 Phenol, 4,4′- cyclohexylidene bis[2-methyl-. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as a...

  14. 40 CFR 721.10049 - Phenol, 4,4′- cyclohexylidene bis[2-methyl-.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Phenol, 4,4â²- cyclohexylidene bis[2... Specific Chemical Substances § 721.10049 Phenol, 4,4′- cyclohexylidene bis[2-methyl-. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as a...

  15. 40 CFR 721.10049 - Phenol, 4,4′- cyclohexylidene bis[2-methyl-.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Phenol, 4,4â²- cyclohexylidene bis[2... Specific Chemical Substances § 721.10049 Phenol, 4,4′- cyclohexylidene bis[2-methyl-. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as a...

  16. Enantioselective Metabolism of Chiral 3-Phenylbutyric Acid, an Intermediate of Linear Alkylbenzene Degradation, by Rhodococcus rhodochrous PB1

    PubMed Central

    Simoni, S.; Klinke, S.; Zipper, C.; Angst, W.; Kohler, H. E.

    1996-01-01

    Rhodococcus rhodochrous PB1 was isolated from compost soil by selective culture with racemic 3-phenylbutyric acid as the sole carbon and energy source. Growth experiments with the single pure enantiomers as well as with the racemate showed that only one of the two enantiomers, (R)-3-phenylbutyric acid, supported growth of strain PB1. Nevertheless, (S)-3-phenylbutyric acid was cometabolically transformed to, presumably, (S)-3-(2,3-dihydroxyphenyl)butyric acid (the absolute configuration at the C-3 atom is not known yet) by (R)-3-phenylbutyric acid-grown cells of strain PB1, as shown by (sup1)H nuclear magnetic resonance spectroscopy of the partially purified compound and gas chromatography-mass spectrometry analysis of the trimethylsilyl derivative. Oxygen uptake rates suggest that either 3-phenylpropionic acid or cinnamic acid (trans-3-phenyl-2-propenoic acid) is the substrate for aromatic ring hydroxylation. This view is substantiated by the fact that 3-(2,3-dihydroxyphenyl)propionic acid was a substrate for meta cleavage in cell extracts of (R)-3-phenylbutyric acid-grown cells of strain PB1. Gas chromatography-mass spectrometry analysis of trimethylsilane-treated ethyl acetate extracts of incubation mixtures showed that both the meta-cleavage product, 2-hydroxy-6-oxo-2,4-nonadiene-1,9-dicarboxylic acid, and succinate, a hydrolysis product thereof, were formed during such incubations. PMID:16535265

  17. 2-Methyl-sulfonyl-4-(trifluoro-meth-yl)benzoic acid.

    PubMed

    Yao, Lin-Shan; We, Bo; Gao, Jin-Sheng

    2012-06-01

    In the title mol-ecule, C(9)H(7)F(3)O(4)S, the S and the methyl C atoms of the methyl-sulfonyl group deviate from the benzene ring plane by 0.185 (2) and -1.394 (3) Å, respectively. In the crystal, O-H⋯O hydrogen bonds link the mol-ecules into chains along [201]. Weak C-H⋯O inter-actions further link these chains into layers parallel to the ac plane. PMID:22719621

  18. Microwave spectrum and structure of 2-methyl-1,3-dioxane

    NASA Astrophysics Data System (ADS)

    Shapkin, A. A.; Galeev, R. V.; Gunderova, L. N.; Fayzullin, M. G.; Mamleev, A. H.

    2006-12-01

    The microwave rotational spectra of parent and five isotopic species with 13C and 180 in natural abundance for 2- methyl-1,3-dioxane, C 5H 100 II, have been observed in the 28.0 - 44.0 GHz frequency region. The a - and c - type transitions with 4 <= J <= 10 have been assigned. The rotational constants for all isotopomers were determined. The substituted coordinates of the heavy atoms were calculated from the principal moments of inertia of normal and 13C(2) 12C 4H 10 160 II, 13C(4) 12C 4H 10 160 II, 13C(5) 12C 4H 10 160 II, 13C(7) 12C 4H 10 160, C 5H 10 160 180 isotopomers using Kraitchman's equations. Partial substituted r s structure of 2-methyl-1,3-dioxane molecule has been determined.

  19. Biochemical properties of a newly synthesized H(+)/K(+) ATPase inhibitor, 1-(2-methyl-4-methoxyphenyl)-4-.

    PubMed

    Cheon, H G; Lim, H; Lee, D H

    2001-01-01

    A new compound, 1-(2-methyl-4-methoxyphenyl)-4-[(3-hydroxypropyl)amino]-6-methyl-2,3-dihydropyrrolo[3,2-c]quinoline (DBM-819), inhibited gastric H(+)/K(+) ATPase in the rabbit (EC 3.6.1.3) with an IC(50) value of 5 microM. However, DBM-819 was a weak inhibitor of kidney Na(+)/K(+) ATPase in the dog, indicating that it has selectivity for the gastric H(+)/K(+) ATPase. The inhibition was reversible and non-competitive with respect to the activating cation K(+). The presence of dithiothreitol did not protect the H(+)/K(+) ATPase from inactivation. The inhibition by DBM-819 was potentiated by acid pretreatment of the compound, suggesting that DBM-819 is converted into a more active intermediate under acidic conditions. The results suggest that DBM-819 is a potent, selective and reversible inhibitor of gastric H(+)/K(+) ATPase, and that the essential cysteine residue may not be involved in the DBM-819-mediated inactivation of gastric H(+)/K(+) ATPase. PMID:11137874

  20. (Biphenyl-2-yl)bromidobis(2-methyl-tetra-hydro-furan-κO)magnesium(II).

    PubMed

    Nordschild, Simon; Wohlgemuth, D; Bolte, Michael

    2009-01-01

    In the title Grignard reagent, [MgBr(C(12)H(9))(C(5)H(10)O)(2)], the Mg centre adopts a distorted tetra-hedral MgCO(2)Br arrangement. The dihedral angle between the two aromatic rings of the biphenyl residue is 44.00 (14)°. Each mol-ecule incorporates one R- and one S-configured 2-methyl-tetra-hydro-furan mol-ecule. PMID:21583743

  1. 75 FR 4288 - Oxirane, 2-Methyl-, Polymer with Oxirane, Dimethyl Ether; Tolerance Exemption

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-01-27

    ...This regulation establishes an exemption from the requirement of a tolerance for residues of oxirane, 2-methyl-,polymer with oxirane, dimethyl ether (CAS Reg. No. 61419-46-3); minimum number average molecular weight (in AMW) 2,800; when used as an inert ingredient in a pesticide chemical formulation under 40 CFR 180.960. BASF Corporation, 100 Campus Dr., Florham Park, NJ 07932 submitted a......

  2. Crystallization of lysozyme with (R)-, (S)- and (RS)-2-methyl-2, 4-pentanediol

    SciTech Connect

    Stauber, Mark; Jakoncic, Jean; Berger, Jacob; Karp, Jerome M.; Axelbaum, Ariel; Sastow, Dahniel; Buldyrev, Sergey V.; Hrnjez, Bruce J.; Asherie, Neer

    2015-03-01

    Crystallization of lysozyme with (R)-2-methyl-2, 4-pentanediol produces more ordered crystals and a higher resolution protein structure than crystallization with (S)-2-methyl-2, 4-pentanediol. The results suggest that chiral interactions with chiral additives are important in protein crystal formation. Chiral control of crystallization has ample precedent in the small-molecule world, but relatively little is known about the role of chirality in protein crystallization. In this study, lysozyme was crystallized in the presence of the chiral additive 2-methyl-2, 4-pentanediol (MPD) separately using the R and S enantiomers as well as with a racemic RS mixture. Crystals grown with (R)-MPD had the most order and produced the highest resolution protein structures. This result is consistent with the observation that in the crystals grown with (R)-MPD and (RS)-MPD the crystal contacts are made by (R)-MPD, demonstrating that there is preferential interaction between lysozyme and this enantiomer. These findings suggest that chiral interactions are important in protein crystallization.

  3. Sulfur-containing flavors: gas phase structures of dihydro-2-methyl-3-thiophenone.

    PubMed

    Mouhib, Halima; Van, Vinh; Stahl, Wolfgang

    2013-08-01

    Dihydro-2-methyl-3-thiophenone was investigated using a combination of quantum chemical calculations and molecular beam Fourier transform microwave spectroscopy. The substance is present in coffee, roasted peanuts, and whiskey. The microwave spectrum was recorded under molecular beam conditions in the frequency range from 9 to 14 GHz. We report on the two main conformers of dihydro-2-methyl-3-thiophenone, for which highly accurate rotational constants and centrifugal distortion constants were obtained. No splittings due to internal rotation of the methyl group could be observed in the microwave spectrum. This is in agreement with the theoretical predictions of the barrier heights, which have been determined to be more than 1000 cm(-1) at the MP2/6-311++G(d,p) level of theory. In addition to the most abundant (32)S-isotopologue of the main conformer, also the (34)S-isotopologue was assigned, which occurs with a natural abundance of about 4%. Using the experimental rotational constants, different quantum chemical calculations were validated for the two observed conformers. To complete the theoretical investigation of dihydro-2-methyl-3-thiophenone, different transition states were optimized to understand the intramolecular conversion between the two conformers at the MP2/6-311++G(d,p) level. The transition states were optimized using the Berny algorithm. PMID:23815419

  4. Cloning and analysis of 1-hydroxy-2-methyl-2-(E)-butenyl-4-diphosphate reductase genes HsHDR1 and HsHDR2 in Huperzia serrate

    PubMed Central

    Lv, Haizhou; Zhang, Xin; Liao, Baosheng; Liu, Wanjing; He, Liu; Song, Jingyuan; Sun, Chao; Luo, Hongmei; Chen, Shilin

    2015-01-01

    We cloned and analyzed the two genes of the 1-hydroxy-2-methyl-2-(E)-butenyl-4-diphosphate reductase (HDR) gene family from Huperzia serrate. The two transcripts coding HDR, named HsHDR1 and HsHDR2, were discovered in the transcriptome dataset of H. serrate and were cloned by reverse transcription-polymerase chain reaction (RT-PCR). The physicochemical properties, protein domains, protein secondary structure, and 3D structure of the putative HsHDR1 and HsHDR2 proteins were analyzed. The full-length cDNA of the HsHDR1 gene contained 1431 bp encoding a putative protein with 476 amino acids, whereas the HsHDR2 gene contained 1428 bp encoding a putative protein of 475 amino acids. These two proteins contained the conserved domain of 1-hydroxy-2-methyl-2-(E)-butenyl-4-diphosphate reductase (PF02401), but without the transmembrane region and signal peptide. The most abundant expression of HsHDR1 and HsHDR2 was detected in H. serrate roots, followed by the stems and leaves. Our results provide a foundation for exploring the function of HsHDR1 and HsHDR2 in terpenoid and sterol biosynthesis in Huperziaceae plants. PMID:26713274

  5. Solubility of carbon dioxide in aqueous solutions of 2-amino-2-methyl-1,3-propanediol

    SciTech Connect

    Baek, J.I.; Yoon, J.H.

    1998-07-01

    The equilibrium solubility of carbon dioxide in aqueous solutions of 2-amino-2-methyl-1,3-propanediol (AMPD) has been measured at (30, 40, and 60) C and the partial pressure of carbon dioxide ranging from (0.5 to 3065) kPa. The concentrations of the aqueous solutions were (10 and 30) mass % AMPD. The tendency of the solubility of carbon dioxide in 30 mass % AMPD aqueous solution at 40 C was found to be similar to that in 30 mass % N-methyldiethanolamine aqueous solution.

  6. The infrared spectra of spiropentane methylenecyclobutane and 2-methyl-1-butene

    NASA Technical Reports Server (NTRS)

    Cleaves, Alden P; Sherrick, Mildred E

    1946-01-01

    The infrared spectra of spiropentane, methylenecyclobutane, and 2-methyl-1-butene were measured in the region from 3 to 14 microns with a rock salt prism spectrometer of medium dispersion. The pure samples were prepared at the NACA Cleveland Laboratory. The vapors of these three C5 hydrocarbons were investigated at room temperature and at pressures in the range from 80 to 300 millimeters of mercury absolute in a 10-centimeter cell. The spectra were compared with each other and with Ramon spectra for the same compounds.

  7. Dispersed Fluorescence Spectroscopy of Jet-Cooled Isobutoxy, 2-METHYL-1-BUTOXY, and Isopentoxy Radicals

    NASA Astrophysics Data System (ADS)

    Reza, Md Asmaul; Reilly, Neil J.; Alam, Jahangir; Mason, Amy; Liu, Jinjun

    2015-06-01

    It is well known that rate constants of certain reactions of alkoxy radicals, e.g., unimolecular dissociation (decomposition by C-C bond fission) and isomerization via 1,5 H-shift, are highly sensitive to the molecular structure. In the present and the next talks, we report dispersed fluorescence (DF) spectra of various alkoxy radicals obtained under supersonic jet-cooled conditions by pumping different vibronic bands of their tilde B ← tilde X laser induced fluorescence (LIF) excitation spectra. This talk focuses on the DF spectra of 2-methyl-1-propoxy (isobutoxy), 2-methyl-1-butoxy, and 3-methyl-1-butoxy (isopentoxy). In all cases, strong CO-stretch progressions were observed, as well as transitions to other vibrational levels, including low-frequency ones. Quantum chemical calculations were carried out to aid the assignment of the DF spectra. Franck-Condon factors were calculated using the ezSpectrum program. Wu, Q.; Liang, G.; Zu, L.; Fang, W. J. Phys. Chem A 2012, 116, 3156-3162. Lin, J.; Wu, Q.; Liang, G.; Zu, L.; Fang, W. RSC Adv. 2012, 2, 583-589. Liang, G.; Liu , C.; Hao, H.; Zu, L.; Fang, W. J. Phys. Chem. A 2013, 117, 13229- 13235. V. Mozhayskiy and A. I. Krylov, http://iopenshell.usc.edu/

  8. Crystallization of lysozyme with (R)-, (S)- and (RS)-2-methyl-2,4-pentanediol

    DOE PAGESBeta

    Stauber, Mark; Jakoncic, Jean; Berger, Jacob; Karp, Jerome M.; Axelbaum, Ariel; Sastow, Dahniel; Buldyrev, Sergey V.; Hrnjez, Bruce J.; Asherie, Neer

    2015-03-01

    Chiral control of crystallization has ample precedent in the small-molecule world, but relatively little is known about the role of chirality in protein crystallization. In this study, lysozyme was crystallized in the presence of the chiral additive 2-methyl-2,4-pentanediol (MPD) separately using the R and S enantiomers as well as with a racemic RS mixture. Crystals grown with (R)-MPD had the most order and produced the highest resolution protein structures. This result is consistent with the observation that in the crystals grown with (R)-MPD and (RS)-MPD the crystal contacts are made by (R)-MPD, demonstrating that there is preferential interaction between lysozymemore » and this enantiomer. These findings suggest that chiral interactions are important in protein crystallization.« less

  9. Interconversion of mechanical and dielectrical relaxation measurements for dicyclohexylmethyl-2-methyl succinate.

    PubMed

    Díaz-Calleja, R; Garcia-Bernabé, A; Sanchis, M J; del Castillo, L F

    2005-11-01

    A comparison between results of dielectrical relaxation and dynamic mechanical spectroscopies is carried out for the alpha-relaxation of the ester dicyclohexyl methyl-2-methyl succinate (DCMMS). The results for the dielectric permittivity and the shear modulus measurements are presented according to the empirical Havriliak-Negami (HN) equation. By using the time-temperature principle a master curve in each case was obtained for several temperatures. The comparative analysis presented here is based on the assumption of a relationship between rotational and shear viscosities. The former one is associated to the dielectrical relaxation, whereas the latter is associated to mechanical relaxation. Both viscosities are not necessarily equal in general, and we assume that the difference between them is an important factor to appropriately compare the dielectrical and mechanical results. PMID:16383609

  10. Biogenic 2-methyl-3-buten-2-ol increases regional ozone and HOx sources

    NASA Astrophysics Data System (ADS)

    Steiner, Allison L.; Tonse, Shaheen; Cohen, Ronald C.; Goldstein, Allen H.; Harley, Robert A.

    2007-08-01

    We present the first regional-scale chemistry simulation investigating the effects of biogenic 2-methyl-3-buten-2-ol (MBO) emissions on air quality. In a central California model domain, MBO emissions have a distinctly different regional pattern than isoprene but have similar daily maxima of about 5 mg m-2 hr-1. MBO oxidation causes an increase in ozone, formaldehyde, acetone and consequently hydrogen radical production (PHOx). The addition of MBO increases the daily maximum ozone as much as 3 ppb near source regions (2-5% in rural areas) and as much as 1 ppb in the Central Valley. Formaldehyde concentrations increase by as much as 1 ppb (40%) over the Sierra Nevada Mountains, increasing the production of HOx by 10-20% and accelerating local chemistry. This indicates that inclusion of MBO and other biogenic oxygenated emissions in regional simulations in the western and southeastern United States is essential for accurate representation of ozone and HOx.

  11. Regeneration of 2-amino-2-methyl-1-propanol used for carbon dioxide absorption.

    PubMed

    Zhang, Pei; Shi, Yao; Wei, Jianwen; Zhao, Wei; Ye, Qing

    2008-01-01

    To improve the efficiency of the carbon dioxide cycling process and to reduce the regeneration energy consumption, a sterically hindered amine of 2-amino-2-methyl-1-propranol (AMP) was investigated to determine its regeneration behavior as a CO2 absorbent. The CO2 absorption and amine regeneration characteristics were experimentally examined under various operating conditions. The regeneration efficiency increased from 86.2% to 98.3% during the temperature range of 358 to 403 K. The most suitable regeneration temperature for AMP was 383 K, in this experiment condition, and the regeneration efficiency of absorption/regenerationruns descended from 98.3% to 94.0%. A number of heat-stable salts (HSS) could cause a reduction in CO2 absorption capacity and regeneration efficiency. The results indicated that aqueous AMP was easier to regenerate with less loss of absorption capacity than other amines, such as, monoethanolamine (MEA), diethanolamine (DEA), diethylenetriamine (DETA), and N-methyldiethanolamine (MDEA). PMID:18572520

  12. Crystallization of lysozyme with (R)-, (S)- and (RS)-2-methyl-2,4-pentanediol

    PubMed Central

    Stauber, Mark; Jakoncic, Jean; Berger, Jacob; Karp, Jerome M.; Axelbaum, Ariel; Sastow, Dahniel; Buldyrev, Sergey V.; Hrnjez, Bruce J.; Asherie, Neer

    2015-01-01

    Chiral control of crystallization has ample precedent in the small-molecule world, but relatively little is known about the role of chirality in protein crystallization. In this study, lysozyme was crystallized in the presence of the chiral additive 2-methyl-2,4-pentanediol (MPD) separately using the R and S enantiomers as well as with a racemic RS mixture. Crystals grown with (R)-MPD had the most order and produced the highest resolution protein structures. This result is consistent with the observation that in the crystals grown with (R)-MPD and (RS)-MPD the crystal contacts are made by (R)-MPD, demonstrating that there is preferential interaction between lysozyme and this enantiomer. These findings suggest that chiral interactions are important in protein crystallization. PMID:25760593

  13. The Limits of Template-Directed Synthesis with Nucleoside-5'-Phosphoro(2-Methyl) Imidazolides

    NASA Technical Reports Server (NTRS)

    Hill, Aubrey R., Jr.; Orgel, Leslie E.; Wu, Taifeng

    1993-01-01

    In earlier work we have shown that C-rich templates containing isolated A, T or G residues and short oligo(G) sequences can be copied effectively using nucleoside-5'-phosphoro(2-methyl)imidazolides as substrates. We now show that isolated A or T residues within an oligo(G) sequence are a complete block to copying and that an isolated C residue is copied inefficiently. Replication is possible only if there are two complementary oligonucleotides each of which acts as a template to facilitate the synthesis of the other. We emphasize the severity of the problems that need to be overcome to make possible non-enzymatic replication in homogeneous aqueous solution. We conclude that an efficient catalyst was involved in the origin of polynucleotide replication.

  14. Molecular structure and charge transfer contributions to nonlinear optical property of 2-Methyl-4-nitroaniline: A DFT study

    NASA Astrophysics Data System (ADS)

    Jasmine, G. Femina; Amalanathan, M.; Roy, S. Dawn Dharma

    2016-05-01

    The Charge transfer contributions to the second-order nonlinear optical properties of 2-Methyl-4-nitroaniline have been performed by means of DFT computation. The vibrational contribution studies of 2-Methyl-4-nitroaniline have also been performed using FTIR, FT-Raman analysis. More support on the experimental findings were added from the quantum chemical studies performed with DFT (B3LYP) method using 6-311++G(d,p)basis sets. Natural bond orbital analysis confirms the presence of intramolecular charge transfer and the hydrogen bonding interaction. The HOMO and LUMO analysis reveals the possibility of charge transfer within the molecule. The first order hyperpolarizability (α0) and related properties (β,α0 and Δα) of 2-Methyl-4-nitroaniline were calculated. In addition, molecular electrostatic potential (MEP), charge analysis also were investigated using theoretical calculations.

  15. The variation trends of SFRP2 methylation of tissue, feces, and blood detection in colorectal cancer development.

    PubMed

    Sui, Chengguang; Ma, Jianzhong; Chen, Qun; Yang, Yang

    2016-07-01

    The susceptibility of secreted frizzled-related protein 2 (SFRP2) methylation in colorectal cancer (CRC) has been studied previously. The aim of this study was to determine the risk sizes and variation trends of SFRP2 methylation in CRC development in Chinese populations. Subgroup meta-analysis and the least-squares curve-fitting method were carried out to analyze the risk of SFRP2 methylation in tissue, feces, and blood detection from 2221 samples, including a total of 1103 cases of CRC, 459 cases of adenoma, 257 cases of polyps, and 402 controls. The data showed that odds ratios (95% confidence intervals) between CRC and controls for tissue, feces, and blood detection were 334.01 (104.42-1068.39), 63.76 (20.62-197.63), and 133.75 (18.32-976.32), respectively. There were also significant differences between tissue and feces or blood as well as between feces and blood methylation frequency. These results showed that the risk size in tissue was much greater than that in feces and that in blood. The results pointed out that three curves in tissue, feces, and blood detection described the variation trends of methylation incidence from the control to polyp, to adenoma and to CRC, and that the variation trend of the risk size of SFRP2 methylation was synchronized with the histological evolution process of CRC. The variation trend of the risk size of SFRP2 methylation incidence is consistent with the histological evolution process of CRC. The susceptibility to SFRP2 methylation is an important biomarker in the study of early diagnosis of CRC and high-risk patients. PMID:26258809

  16. Alterations of Cyclooxygenase-2 Methylation Levels Before and After Intervention Trial to Prevent Gastric Cancer in a Chinese Population.

    PubMed

    Zhang, Yang; Zeng, Hong-Mei; Nie, Xiao-Rui; Zhang, Lian; Ma, Jun-Ling; Li, Ji-You; Pan, Kai-Feng; You, Wei-Cheng

    2016-06-01

    To explore the epigenetic mechanisms underlying the effects of anti-Helicobacter pylori (H. pylori) alone and combined with COX-2 inhibitor (celecoxib), we dynamically evaluated the associations between COX-2 methylation alterations and gastric lesion evolution during the process of interventions. In a total of 809 trial participants COX-2 methylation levels were quantitatively detected before and after treatment. The self-comparison at the same stomach site for each subject showed significant methylation alteration differences among intervention groups (P < 0.001). With placebo group as reference, COX-2 methylation levels were decreased in anti-H. pylori [OR, 3.30; 95% confidence interval (CI), 2.16-5.02], celecoxib (OR, 2.04; 95% CI, 1.36-3.07), and anti-H. pylori followed by celecoxib (OR, 2.10; 95% CI, 1.38-3.17) groups. When stratified by baseline histology, the three active arms significantly decreased COX-2 methylation levels in indefinite dysplasia/dysplasia subjects, and ORs were 3.65 (95% CI, 1.96-6.80) for anti-H. pylori, 2.43 (95% CI 1.34-4.39) for celecoxib, and 2.80 (95% CI, 1.52-5.15) for anti-H. pylori followed by celecoxib, respectively. No additive effect on COX-2 methylation was found for anti-H. pylori followed by celecoxib than two treatments alone. Compared with subjects without methylation reduction, higher opportunity for gastric lesion regression was found in subjects with decreased COX-2 methylation levels, especially for indefinite dysplasia/dysplasia subjects (OR, 1.92; 95% CI, 1.03-3.60). These findings suggest that anti-H. pylori or celecoxib treatment alone could decrease COX-2 methylation levels in gastric mucosa. COX-2 methylation alteration was associated with the regression of indefinite dysplasia/dysplasia, which might serve as a potential biomarker for chemoprevention efficacy. Cancer Prev Res; 9(6); 484-90. ©2016 AACR. PMID:27020655

  17. Novel ring A stereoisomers of 2-methyl-1alpha,25-dihydroxyvitamin D(3) and 2-methyl-20-epi-1alpha,25-dihydroxyvitamin D(3): transactivation of target genes and modulation of differentiation in human promyelocytic leukemia (HL-60) cells.

    PubMed

    Nakagawa, K; Kurobe, M; Ozono, K; Konno, K; Fujishima, T; Takayama, H; Okano, T

    2000-03-15

    We evaluated the biological activity of two sets of ring A stereoisomers of 2-methyl-1alpha,25-dihydroxyvitamin D(3) (2-methyl-1alpha,25(OH)(2)D(3)) and 2-methyl-20-epi-1alpha, 25-dihydroxyvitamin D(3) (2-methyl-20-epi-1alpha,25(OH)(2)D(3)) in terms of the following: transactivation of a rat 25-hydroxyvitamin D(3)-24-hydroxylase gene promoter including two vitamin D response elements (VDREs) and a human osteocalcin gene promoter including a VDRE in transfected human osteosarcoma (MG-63) cells; a vitamin D receptor (VDR)-mediated response using a VDR-GAL4 one-hybrid luciferase reporter system and a retinoid X receptor alpha (RXRalpha)-mediated response using an expressed VDR/RXRalpha-GAL4 modified two-hybrid luciferase reporter system in transfected human epitheloid carcinoma, cervix (HeLa) cells; and modulation of cell surface CD11b antigen expression in human leukemia (HL-60) cells. All the diastereomers of both analogues exhibited unique biological activity profiles depending upon the configurations of the C-1 and C-3 hydroxyl groups, the C-2 methyl group in ring A, and the C-20 methyl group in the side chain. Of the eight possible diastereomers of the 2-methyl analogues, 2alpha-methyl-1alpha,25(OH)(2)D(3) was the most potent and exhibited comparable or even greater biological potency than 1alpha,25(OH)(2)D(3). Of the eight possible diastereomers of the 2-methyl-20-epi analogues, 2alpha-methyl-20-epi-1alpha,25(OH)(2)D(3) was the most potent and exhibited 100- to 200-fold higher transcriptional potencies than 1alpha,25(OH)(2)D(3) and exceptionally high cell regulatory activities. 2beta-methyl-20-epi-1alpha,25(OH)(2)D(3) was nearly as potent as its 2-epimer, 2alpha-methyl-20-epi-1alpha,25(OH)(2)D(3), whereas its 20-epimer, 2beta-methyl-1alpha,25(OH)(2)D(3), was almost completely biologically inactive. In these respects, it can be postulated that the double modification of 2-methyl substitution and 20-epimerization to 1alpha,25(OH)(2)D(3) induces remarkable changes

  18. Solubility and diffusivity of N{sub 2}O and CO{sub 2} in (diethanolamine + N-methyldiethanolamine + water) and in (diethanolamine + 2-amino-2-methyl-1-propanol + water)

    SciTech Connect

    Li, M.H.; Lee, W.C.

    1996-05-01

    Acid gases such as CO{sub 2} and H{sub 2}S are frequently removed from natural gas, synthetic natural gas, and other process gas streams by means of absorption into aqueous alkanol-amine solutions. The solubility and diffusivity of N{sub 2}O in (diethanolamine + N-methyldiethanolamine + water) and in (diethanolamine + 2-amino-2-methyl-1-propanol + water) were measured at (30, 35, and 40)C and at atmospheric pressure. Five (diethanolamine + N-methyldiethanolamine + water) and four (diethanolamine + 2-amino-2-methyl-1-propanol + water) systems were studied. The total amine mass percent in all cases was 30. A solubility apparatus was used to measure the solubility of N{sub 2}O in amine solutions. The diffusivity was measured by a wetted wall column absorber. The N{sub 2}O analogy was used to estimate the solubility and diffusivity of CO{sub 2} in (diethanolamine + N-methyldiethanolamine + water) and in (diethanolamine + 2-amino-2-methyl-1-propanol + water).

  19. Solubility and diffusivity of N{sub 2}O and CO{sub 2} in (monoethanolamine + N-methyldiethanolamine + water) and in (monoethanolamine + 2-amino-2-methyl-1-propanol + water)

    SciTech Connect

    Li, M.H.; Lai, M.D.

    1995-03-01

    Solutions of amines are frequently used in gas-treating processes to remove acid gases, such as CO{sub 2} and H{sub 2}S, from gas streams in the natural gas and synthetic ammonia industries and petroleum chemical plants. The solubility and diffusivity of N{sub 2}O in (monoethanolamine + N-methyldiethanolamine + water) and in (monoethanolamine + 2-amino-2-methyl-l-propanol + water) were measured at 30, 35, and 40 C and at atmospheric pressure. Six (monoethanolamine + N-methyldiethanolamine + water) and five (monoethanolamine + 2-amino-2-methyl-l-propanol + water) systems were studied. The total amine mass percent in all cases was 30. The solubilities were measured by a solubility apparatus similar to that of Haimour and Sandall (1984). A wetted wall column absorber was used to obtain the diffusivity of N{sub 2}O in amines. The N{sub 2}O solubilities in amine solutions have been correlated on the basis of the excess Henry constant correlation of Wang et al. (1992). The N{sub 2}O analogy was used to estimate the solubility and diffusivity of CO{sub 2} in (monoethanolamine + N-methyldiethanolamine + water) and in (monoethanolamine + 2-amino-2-methyl-l-propanol + water).

  20. Metabolic pathway involved in 2-methyl-6-ethylaniline degradation by Sphingobium sp. strain MEA3-1 and cloning of the novel flavin-dependent monooxygenase system meaBA.

    PubMed

    Dong, Weiliang; Chen, Qiongzhen; Hou, Ying; Li, Shuhuan; Zhuang, Kai; Huang, Fei; Zhou, Jie; Li, Zhoukun; Wang, Jue; Fu, Lei; Zhang, Zhengguang; Huang, Yan; Wang, Fei; Cui, Zhongli

    2015-12-01

    2-Methyl-6-ethylaniline (MEA) is the main microbial degradation intermediate of the chloroacetanilide herbicides acetochlor and metolachlor. Sphingobium sp. strain MEA3-1 can utilize MEA and various alkyl-substituted aniline and phenol compounds as sole carbon and energy sources for growth. We isolated the mutant strain MEA3-1Mut, which converts MEA only to 2-methyl-6-ethyl-hydroquinone (MEHQ) and 2-methyl-6-ethyl-benzoquinone (MEBQ). MEA may be oxidized by the P450 monooxygenase system to 4-hydroxy-2-methyl-6-ethylaniline (4-OH-MEA), which can be hydrolytically spontaneously deaminated to MEBQ or MEHQ. The MEA microbial metabolic pathway was reconstituted based on the substrate spectra and identification of the intermediate metabolites in both the wild-type and mutant strains. Plasmidome sequencing indicated that both strains harbored 7 plasmids with sizes ranging from 6,108 bp to 287,745 bp. Among the 7 plasmids, 6 were identical, and pMEA02' in strain MEA3-1Mut lost a 37,000-bp fragment compared to pMEA02 in strain MEA3-1. Two-dimensional electrophoresis (2-DE) and protein mass fingerprinting (PMF) showed that MEA3-1Mut lost the two-component flavin-dependent monooxygenase (TC-FDM) MeaBA, which was encoded by a gene in the lost fragment of pMEA02. MeaA shared 22% to 25% amino acid sequence identity with oxygenase components of some TC-FDMs, whereas MeaB showed no sequence identity with the reductase components of those TC-FDMs. Complementation with meaBA in MEA3-1Mut and heterologous expression in Pseudomonas putida strain KT2440 resulted in the production of an active MEHQ monooxygenase. PMID:26386060

  1. Metabolic Pathway Involved in 2-Methyl-6-Ethylaniline Degradation by Sphingobium sp. Strain MEA3-1 and Cloning of the Novel Flavin-Dependent Monooxygenase System meaBA

    PubMed Central

    Dong, Weiliang; Chen, Qiongzhen; Hou, Ying; Li, Shuhuan; Zhuang, Kai; Huang, Fei; Zhou, Jie; Li, Zhoukun; Wang, Jue; Fu, Lei; Zhang, Zhengguang; Huang, Yan; Wang, Fei

    2015-01-01

    2-Methyl-6-ethylaniline (MEA) is the main microbial degradation intermediate of the chloroacetanilide herbicides acetochlor and metolachlor. Sphingobium sp. strain MEA3-1 can utilize MEA and various alkyl-substituted aniline and phenol compounds as sole carbon and energy sources for growth. We isolated the mutant strain MEA3-1Mut, which converts MEA only to 2-methyl-6-ethyl-hydroquinone (MEHQ) and 2-methyl-6-ethyl-benzoquinone (MEBQ). MEA may be oxidized by the P450 monooxygenase system to 4-hydroxy-2-methyl-6-ethylaniline (4-OH-MEA), which can be hydrolytically spontaneously deaminated to MEBQ or MEHQ. The MEA microbial metabolic pathway was reconstituted based on the substrate spectra and identification of the intermediate metabolites in both the wild-type and mutant strains. Plasmidome sequencing indicated that both strains harbored 7 plasmids with sizes ranging from 6,108 bp to 287,745 bp. Among the 7 plasmids, 6 were identical, and pMEA02′ in strain MEA3-1Mut lost a 37,000-bp fragment compared to pMEA02 in strain MEA3-1. Two-dimensional electrophoresis (2-DE) and protein mass fingerprinting (PMF) showed that MEA3-1Mut lost the two-component flavin-dependent monooxygenase (TC-FDM) MeaBA, which was encoded by a gene in the lost fragment of pMEA02. MeaA shared 22% to 25% amino acid sequence identity with oxygenase components of some TC-FDMs, whereas MeaB showed no sequence identity with the reductase components of those TC-FDMs. Complementation with meaBA in MEA3-1Mut and heterologous expression in Pseudomonas putida strain KT2440 resulted in the production of an active MEHQ monooxygenase. PMID:26386060

  2. Canopy Level Emissions of 2-methyl-3-buten-2-ol, monoterpenes, and sesquiterpenes from a Pinus taeda Experimental Plantation

    EPA Science Inventory

    Emissions of biogenic volatile organic compounds (BVOC) observed during 2007 from a Pinus taeda experimental plantation in Central North Carolina are compared with model estimates from MEGAN 2.1. Relaxed Eddy Accumulation (REA) estimates of 2-methyl-3-buten-2-ol (MBO) fluxes are ...

  3. Free volume model for the unexpected effect of C2-methylation on the properties of imidazolium ionic liquids.

    PubMed

    Chen, Zheng Jian; Lee, Jong-Min

    2014-03-13

    For 1-alkyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imides and their cationic C2-methylated isomers, that is, [C(n)MIm]NTf2 and [C(n-1)DMIm]NTf2 (n = 3-8), the latter always has much higher viscosities (∼1.66 times at 25 °C) than the former. This finding is unexpected and contrary to the loss of the predominant hydrogen bonding between the cation and anion, caused by the C2-methylation in the imidazolium ionic liquids. In the present study, we propose a free volume model to explain this mysterious phenomenon. For the isomeric pairs, [C(n-1)DMIm]NTf2 was found to possess less unoccupied (free) volume than [C(n)MIm]NTf2 by ∼4.5 mL mol(-1) determined by both Fürth's surface tension and molar volume methods, and the free volume difference can be quantitatively correlated with the C2-methylation effect on viscosity. Generally, the less free volume in [C(n-1)DMIm]NTf2 relative to [C(n)MIm]NTf2 reduces the number of the hole carriers for molecular transport with a resulting increase in viscosity. Besides, the free volume model can also be applied to account for the C2-methylation effect on other properties, such as conductivity, surface tension, density, and refractive index. PMID:24576309

  4. Organosulfates as Tracers for Secondary Organic Aerosol (SOA) Formation from 2-Methyl-3-Buten-2 ol (MBO) in the Atmosphere

    EPA Science Inventory

    2-Methyl-3-buten-2-ol (MBO) is an important biogenic volatile organic compound (BVOC) emitted by pine trees and a potential precursor of atmospheric secondary organic aerosol (SOA) in forested regions. In the present study, hydroxyl radical (OH)-initiated oxidation of MBO was exa...

  5. Bacterial Degradation of tert-Amyl Alcohol Proceeds via Hemiterpene 2-Methyl-3-Buten-2-ol by Employing the Tertiary Alcohol Desaturase Function of the Rieske Nonheme Mononuclear Iron Oxygenase MdpJ

    PubMed Central

    Schuster, Judith; Schäfer, Franziska; Hübler, Nora; Brandt, Anne; Rosell, Mònica; Härtig, Claus; Harms, Hauke; Müller, Roland H.

    2012-01-01

    Tertiary alcohols, such as tert-butyl alcohol (TBA) and tert-amyl alcohol (TAA) and higher homologues, are only slowly degraded microbially. The conversion of TBA seems to proceed via hydroxylation to 2-methylpropan-1,2-diol, which is further oxidized to 2-hydroxyisobutyric acid. By analogy, a branched pathway is expected for the degradation of TAA, as this molecule possesses several potential hydroxylation sites. In Aquincola tertiaricarbonis L108 and Methylibium petroleiphilum PM1, a likely candidate catalyst for hydroxylations is the putative tertiary alcohol monooxygenase MdpJ. However, by comparing metabolite accumulations in wild-type strains of L108 and PM1 and in two mdpJ knockout mutants of strain L108, we could clearly show that MdpJ is not hydroxylating TAA to diols but functions as a desaturase, resulting in the formation of the hemiterpene 2-methyl-3-buten-2-ol. The latter is further processed via the hemiterpenes prenol, prenal, and 3-methylcrotonic acid. Likewise, 3-methyl-3-pentanol is degraded via 3-methyl-1-penten-3-ol. Wild-type strain L108 and mdpJ knockout mutants formed isoamylene and isoprene from TAA and 2-methyl-3-buten-2-ol, respectively. It is likely that this dehydratase activity is catalyzed by a not-yet-characterized enzyme postulated for the isomerization of 2-methyl-3-buten-2-ol and prenol. The vitamin requirements of strain L108 growing on TAA and the occurrence of 3-methylcrotonic acid as a metabolite indicate that TAA and hemiterpene degradation are linked with the catabolic route of the amino acid leucine, including an involvement of the biotin-dependent 3-methylcrotonyl coenzyme A (3-methylcrotonyl-CoA) carboxylase LiuBD. Evolutionary aspects of favored desaturase versus hydroxylation pathways for TAA conversion and the possible role of MdpJ in the degradation of higher tertiary alcohols are discussed. PMID:22194447

  6. Statistical thermodynamics of 1-butanol, 2-methyl-1-propanol, and butanal.

    PubMed

    Seal, Prasenjit; Papajak, Ewa; Yu, Tao; Truhlar, Donald G

    2012-01-21

    The purpose of the present investigation is to calculate partition functions and thermodynamic quantities, viz., entropy, enthalpy, heat capacity, and Gibbs free energies, for 1-butanol, 2-methyl-1-propanol, and butanal in the vapor phase. We employed the multi-structural (MS) anharmonicity method and electronic structure calculations including both explicitly correlated coupled cluster theory and density functional theory. The calculations are performed using all structures for each molecule and employing both the local harmonic approximation (MS-LH) and the inclusion of torsional anharmonicity (MS-T). The results obtained from the MS-T calculations are in excellent agreement with experimental data taken from the Thermodynamics Research Center data series and the CRC Handbook of Chemistry and Physics, where available. They are also compared with Benson's empirical group additivity values, where available; in most cases, the present results are more accurate than the group additivity values. In other cases, where experimental data (but not group additivity values) are available, we also obtain good agreement with experiment. This validates the accuracy of the electronic structure calculations when combined with the MS-T method for estimating the thermodynamic properties of systems with multiple torsions, and it increases our confidence in the predictions made with this method for molecules and temperatures where experimental or empirical data are not available. PMID:22280759

  7. Performance of tris(2-methyl-8-quinolinolato)aluminum as fluorescent anionophore.

    PubMed

    Yuchi, Akio; Hiramatsu, Hiroaki; Ohara, Miyuki; Ohata, Nayumi

    2003-08-01

    An X-ray crystallographic study demonstrated that the tris complex of Al3+ with 2-methyl-8-quinolinol (Hmq), [Al(mq)3], had a discrete octahedral geometry in a meridional configuration with respect to mq-; the Al-N bonds were appreciably elongated. In organic solvents, the complex reacted with water to give a lower species of a mu-oxo dimer, [Al2O(mq)4], and a protonated ligand, depending on the concentrations of water and of excess ligand. None of Cl-, Br-, I-, ClO4-, and CH3COO- showed any reactions with [Al(mq)3]. The anions having high affinities to Al3+, such as H2PO4- and F-, replaced all the ligand. The anion having a lower affinity, HSO4-, exclusively formed a mixed-ligand complex of [Al(mq)2HSO4], which had a more intense fluorescence than the others. In contrast, the corresponding 8-quinolinol (Hq) complex, [Alq3], showed no reactions with any anions. PMID:12945673

  8. DFT simulations and vibrational spectra of 2-amino-2-methyl-1,3-propanediol

    NASA Astrophysics Data System (ADS)

    Renuga Devi, T. S.; Sharmi kumar, J.; Ramkumaar, G. R.

    2014-12-01

    The FTIR and FT-Raman spectra of 2-amino-2-methyl-1,3-propanediol were recorded in the regions 4000-400 cm-1 and 4000-50 cm-1 respectively. The structural and spectroscopic data of the molecule in the ground state were calculated using Hartee-Fock and density functional method (B3LYP) with the augmented-correlation consistent-polarized valence double zeta (aug-cc-pVDZ) basis set. The most stable conformer was optimized and the structural and vibrational parameters were determined based on this. The complete assignments were performed on the basis of the Potential Energy Distribution (PED) of the vibrational modes, calculated using Vibrational Energy Distribution Analysis (VEDA) 4 program. With the observed FTIR and FT-Raman data, a complete vibrational assignment and analysis of the fundamental modes of the compound were carried out. Thermodynamic properties and Mulliken charges were calculated using both Hartee-Fock and density functional method using the aug-cc-pVDZ basis set and compared. The calculated HOMO-LUMO energy gap revealed that charge transfer occurs within the molecule. 1H and 13C NMR chemical shifts of the molecule were calculated using Gauge-Independent Atomic Orbital (GIAO) method and were compared with experimental results.

  9. Dispersed Fluorescence Spectroscopy of Jet-Cooled Isobutoxy and 2-Methyl-1-butoxy Radicals.

    PubMed

    Reza, Md Asmaul; Paul, Anam C; Reilly, Neil J; Alam, Jahangir; Liu, Jinjun

    2016-09-01

    We report dispersed fluorescence (DF) spectra of the isobutoxy and 2-methyl-1-butoxy radicals produced by photolysis of corresponding nitrites in supersonic jet expansion. Different vibrational structures have been observed in the DF spectra when different vibronic bands in the laser-induced fluorescence (LIF) spectra of each radical were pumped, which suggests that those vibronic bands be assigned to different conformers. Spectra simulated using calculated vibrational frequencies and Franck-Condon factors well reproduce the experimentally observed ones and support the assignment of the vibronic bands in the LIF spectra to the two lowest-energy conformers of each radical. DF spectra obtained by pumping the B̃ ← X̃ origin bands of the LIF spectra are dominated by CO stretch progressions because of the large difference in CO bond length between the ground (X̃) and the second excited (B̃) electronic states. Furthermore, with non-CO stretch bands pumped, the DF spectra are dominated by progressions of combination bands of the CO stretch and the pumped modes as a result of Duschinsky mixing. Ã-X̃ separation of both conformers of the isobutoxy radical has also been determined in the experiment. PMID:27504673

  10. Association between SMN2 methylation and disease severity in Chinese children with spinal muscular atrophy* #

    PubMed Central

    Cao, Yan-yan; Qu, Yu-jin; He, Sheng-xi; Li, Yan; Bai, Jin-li; Jin, Yu-wei; Wang, Hong; Song, Fang

    2016-01-01

    The homozygous loss of the survival motor neuron 1 (SMN1) gene is the primary cause of spinal muscular atrophy (SMA), a neuromuscular degenerative disease. A genetically similar gene, SMN2, which is not functionally equivalent in all SMA patients, modifies the clinical SMA phenotypes. We analyzed the methylation levels of 4 CpG islands (CGIs) in SMN2 in 35 Chinese children with SMA by MassARRAY. We found that three CpG units located in CGI 1 (nucleotides (nt) −871, −735) and CGI 4 (nt +999) are significantly hypomethylated in SMA type III compared with type I or II children after receiving Bonferroni correction. In addition to the differentially methylated CpG unit of nt −871, the methylation level of the nt −290/−288/−285 unit was negatively correlated with the expression of SMN2 full-length transcripts (SMN2-fl). In addition, the methylation level at nt +938 was inversely proportional to the ratio of SMN2-fl and lacking exon 7 transcripts (SMN2-(7, fl/(7), and was not associated with the SMN2 transcript levels. Thus, we can conclude that SMN2 methylation may regulate the SMA disease phenotype by modulating its transcription. PMID:26739529

  11. Diacetylene and Polydiacetylene Derivatives of 2-Methyl-4-Nitroaniline for Second-Harmonic Generation

    NASA Technical Reports Server (NTRS)

    Paley, M. S.; Frazier, D. O.; McManus, S. P.; Zutaut, S. E.; Sanghadasa, M.

    1993-01-01

    A novel diacetylene derivative of 2-Methyl-4-NitroAniline (MNA), a well-known material for Second-Harmonic Generation (SHG), is synthesized. This monomer DiAcetylene MethylNitroAniline, (DAMNA) is characterized by means of the Kurtz technique at 1064 nm and is found to have an SHG powder efficiency 62.5 % that of MNA itself. Thin crystalline films of DAMNA are grown onto quartz, Teflon, and Kapton substrates by means of vapor deposition in vacuum. These films are then polymerized in the solid state by exposure to long-wavelength UV radiation to give crystalline polydiacetylene thin films (PDAMNA). The films are next characterized for SHG, using an unpolymerized DAMNA film as a reference. Interestingly, films grown onto Teflon exhibit greater orientation and significantly greater SHG than those grown onto quartz and Kapton. This result is promising in that it demonstrates the potential of PDAMNA as both a crystalline and polymeric material for SHG applications, in which highly oriented thin films are desired. Computational modeling (usingAM1) is also carried out on DAMNA and is compared to the experimental results.

  12. Ferulic acid enhances the vasorelaxant effect of epigallocatechin gallate in tumor necrosis factor-alpha-induced inflammatory rat aorta.

    PubMed

    Zhao, Jian; Suyama, Aki; Tanaka, Mitsuru; Matsui, Toshiro

    2014-07-01

    Previously, we demonstrated synergistic enhancement of vasorelaxation by combination treatment with Trp-His and epigallocatechin gallate (EGCg) in intact rat aorta. The aim of the present study was to determine whether this vasorelaxant synergy could be recapitulated in tumor necrosis factor-alpha (TNF-α)-induced inflammatory rat aorta, and to determine the extent of its modulation by anti-inflammatory phenolic acids. Synergistic enhancement of vasorelaxation in rat aorta by Trp-His and EGCg was significantly attenuated in the presence of TNF-α, an effect that was reversed by the addition of ferulic acid (FA, 250 μM). Moreover, FA markedly enhanced EGCg-induced vasorelaxation, but not Trp-His-induced vasorelaxation, in TNF-α-treated aorta. Structure-activity analysis showed that the unsaturated 2-propenoic moiety and the methoxy group of FA were important for the enhancement of vasorelaxation by EGCg. The stimulation of EGCg-induced vasorelaxation by FA was antagonized by the nitric oxide synthase inhibitor N(G)-monomethyl-L-arginine acetate, while FA enhanced vasorelaxant properties of the endothelial nitric oxide (NO) synthase activator acetylcholine in TNF-α-treated inflammatory aorta. Moreover, the EGCg-stimulated NO production was also enhanced by FA in TNF-α-treated aorta. These data indicate that stimulation of NO production by FA enhances the vasorelaxant properties of EGCg in TNF-α-induced inflammatory aorta. PMID:24794014

  13. Experimental and Kinetic Modeling Study of 2-Methyl-2-Butene: Allylic Hydrocarbon Kinetics.

    PubMed

    Westbrook, Charles K; Pitz, William J; Mehl, Marco; Glaude, Pierre-Alexandre; Herbinet, Olivier; Bax, Sarah; Battin-Leclerc, Frederique; Mathieu, Olivier; Petersen, Eric L; Bugler, John; Curran, Henry J

    2015-07-16

    Two experimental studies have been carried out on the oxidation of 2-methyl-2-butene, one measuring ignition delay times behind reflected shock waves in a stainless steel shock tube, and the other measuring fuel, intermediate, and product species mole fractions in a jet-stirred reactor (JSR). The shock tube ignition experiments were carried out at three different pressures, approximately 1.7, 11.2, and 31 atm, and at each pressure, fuel-lean (ϕ = 0.5), stoichiometric (ϕ = 1.0), and fuel-rich (ϕ = 2.0) mixtures were examined, with each fuel/oxygen mixture diluted in 99% Ar, for initial postshock temperatures between 1330 and 1730 K. The JSR experiments were performed at nearly atmospheric pressure (800 Torr), with stoichiometric fuel/oxygen mixtures with 0.01 mole fraction of 2M2B fuel, a residence time in the reactor of 1.5 s, and mole fractions of 36 different chemical species were measured over a temperature range from 600 to 1150 K. These JSR experiments represent the first such study reporting detailed species measurements for an unsaturated, branched hydrocarbon fuel larger than iso-butene. A detailed chemical kinetic reaction mechanism was developed to study the important reaction pathways in these experiments, with particular attention on the role played by allylic C-H bonds and allylic pentenyl radicals. The results show that, at high temperatures, this olefinic fuel reacts rapidly, similar to related alkane fuels, but the pronounced thermal stability of the allylic pentenyl species inhibits low temperature reactivity, so 2M2B does not produce "cool flames" or negative temperature coefficient behavior. The connections between olefin hydrocarbon fuels, resulting allylic fuel radicals, the resulting lack of low-temperature reactivity, and the gasoline engine concept of octane sensitivity are discussed. PMID:25822578

  14. Continuous hydrogenation of ethyl levulinate to γ-valerolactone and 2-methyl tetrahydrofuran over alumina doped Cu/SiO2 catalyst: the potential of commercialization

    PubMed Central

    Zheng, Junlin; Zhu, Junhua; Xu, Xuan; Wang, Wanmin; Li, Jiwen; Zhao, Yan; Tang, Kangjian; Song, Qi; Qi, Xiaolan; Kong, Dejin; Tang, Yi

    2016-01-01

    Hydrogenation of levulinic acid (LA) and its esters to produce γ-valerolactone (GVL) and 2-methyl tetrahydrofuran (2-MTHF) is a key step for the utilization of cellulose derived LA. Aiming to develop a commercially feasible base metal catalyst for the production of GVL from LA, with satisfactory activity, selectivity, and stability, Al2O3 doped Cu/SiO2 and Cu/SiO2 catalysts were fabricated by co-precipitation routes in parallel. The diverse physio-chemical properties of these two catalysts were characterized by XRD, TEM, dissociative N2O chemisorptions, and Py-IR methods. The catalytic properties of these two catalysts were systematically assessed in the continuous hydrogenation of ethyl levulinate (EL) in a fixed-bed reactor. The effect of acidic property of the SiO2 substrate on the catalytic properties was investigated. To justify the potential of its commercialization, significant attention was paid on the initial activity, proper operation window, by-products control, selectivity, and stability of the catalyst. The effect of reaction conditions, such as temperature and pressure, on the performance of the catalyst was also thoroughly studied. The development of alumina doped Cu/SiO2 catalyst strengthened the value-chain from cellulose to industrially important chemicals via LA and GVL. PMID:27377401

  15. Continuous hydrogenation of ethyl levulinate to γ-valerolactone and 2-methyl tetrahydrofuran over alumina doped Cu/SiO2 catalyst: the potential of commercialization

    NASA Astrophysics Data System (ADS)

    Zheng, Junlin; Zhu, Junhua; Xu, Xuan; Wang, Wanmin; Li, Jiwen; Zhao, Yan; Tang, Kangjian; Song, Qi; Qi, Xiaolan; Kong, Dejin; Tang, Yi

    2016-07-01

    Hydrogenation of levulinic acid (LA) and its esters to produce γ-valerolactone (GVL) and 2-methyl tetrahydrofuran (2-MTHF) is a key step for the utilization of cellulose derived LA. Aiming to develop a commercially feasible base metal catalyst for the production of GVL from LA, with satisfactory activity, selectivity, and stability, Al2O3 doped Cu/SiO2 and Cu/SiO2 catalysts were fabricated by co-precipitation routes in parallel. The diverse physio-chemical properties of these two catalysts were characterized by XRD, TEM, dissociative N2O chemisorptions, and Py-IR methods. The catalytic properties of these two catalysts were systematically assessed in the continuous hydrogenation of ethyl levulinate (EL) in a fixed-bed reactor. The effect of acidic property of the SiO2 substrate on the catalytic properties was investigated. To justify the potential of its commercialization, significant attention was paid on the initial activity, proper operation window, by-products control, selectivity, and stability of the catalyst. The effect of reaction conditions, such as temperature and pressure, on the performance of the catalyst was also thoroughly studied. The development of alumina doped Cu/SiO2 catalyst strengthened the value-chain from cellulose to industrially important chemicals via LA and GVL.

  16. Photodissociation dynamics of 2-nitropropane and 2-methyl-2-nitropropane at 248 and 193 nm.

    PubMed

    Sengupta, Sumana; Indulkar, Yogesh; Kumar, Awadhesh; Dhanya, Suresh; Naik, Prakash Dattatray; Bajaj, Parma Nand

    2008-12-11

    Dynamics of formation of electronically excited NO2 and formation of OH fragment, during photo dissociation of 2-nitropropane (NP) and 2-methyl-2-nitropropane (MNP), were investigated at 193 and 248 nm. The radiative lifetime of the electronically excited NO2 fragment, observed at 193 nm, was measured to be 1.2 ( 0.1 micros and the rate coefficient of quenching of its emission by MNP was measured as (2.7 ( 0.1) x 10(-10) molecule(-1) cm3 s(-1). Formation of the ground electronic state of OH was confirmed in both molecules. State selective laser induced fluorescence technique was used to detect the nascent OH (X 2Pi, v'', J'') fragments in different ro-vibrational states, and to obtain information on energy partitioning. Though MNP and NP differ in the types of the available H atoms, the dynamics of OH formation is found to be the same in both. The relative population in different rotational states does not follow Boltzmann equilibrium distribution in both the molecules at 193 and 248 nm. The translational energies of the OH fragments, calculated from the Doppler width, are 21.2 ( 7.2 and 25.0 ( 2.5 kcal mol-1 for NP at 248 and 193 nm, respectively. The translational energies of the OH fragments, in the case of MNP, are found to be lower, 17.5 ( 4.1 and 22.0 ( 3.2 kcal mol-1,respectively, at 248 nm 193 nm. These results are compared with the earlier reports on photodissociation of nitromethane (NM), nitroethane (NE), and other nitroalkanes. All possible dissociation pathways of these molecules--NM, NE, NP, and MNPs leading to the formation of the OH fragment were investigated computationally, with geometry optimization at the B3LYP/6-311+G(d,p) level and energy calculation at the MP4(SDQ)/6-311+G (d,p) level. The results suggest that in NM, OH is formed after isomerization to CH2N(OH)O, whereas in all other cases OH is formed from HONO, a primary product of molecular elimination of nitroalkanes, formed with sufficient internal energy. PMID:19053556

  17. Toxicokinetics, including saturable protein binding, of 4-chloro-2-methyl phenoxyacetic acid (MCPA) in patients with acute poisoning.

    PubMed

    Roberts, Darren M; Dawson, Andrew H; Senarathna, Lalith; Mohamed, Fahim; Cheng, Ron; Eaglesham, Geoffrey; Buckley, Nick A

    2011-03-25

    Human data on protein binding and dose-dependent changes in toxicokinetics for MCPA are very limited. 128 blood samples were obtained in 49 patients with acute MCPA poisoning and total and unbound concentrations of MCPA were determined. The Scatchard plot was biphasic suggesting protein binding to two sites. The free MCPA concentration increased when the total concentration exceeded 239mg/L (95% confidence interval 198-274mg/L). Nonlinear regression using a two-site binding hyperbola model estimated saturation of the high affinity binding site at 115mg/L (95%CI 0-304). Further analyses using global fitting of serial data and adjusting for the concentration of albumin predicted similar concentrations for saturable binding (184mg/L and 167mg/L, respectively) without narrowing the 95%CI. In 25 patients, the plasma concentration-time curves for both bound and unbound MCPA were approximately log-linear which may suggest first order elimination, although sampling was infrequent so zero order elimination cannot be excluded. Using a cut-off concentration of 200mg/L, the half-life of MCPA at higher concentrations was 25.5h (95%CI 15.0-83.0h; n=16 patients) compared to 16.8h (95%CI 13.6-22.2h; n=10 patients) at lower concentrations. MCPA is subject to saturable protein binding but the influence on half-life appears marginal. PMID:21256202

  18. Tris[4-bromo-2-(methyl­imino­meth­yl)phenolato-κ2 N,O]cobalt(III)

    PubMed Central

    Huang, Qiu-Ping; Zhang, Chun-Lian; Zhao, Ru-Xia; Yang, Li; Jiang, Xi-Fu

    2013-01-01

    In the title compound, [Co(C8H7BrNO)3], the CoIII ion is coordinated in a slightly distorted octa­hedral environment by three N atoms and three O atoms from three bidentate 4-bromo-2-(methyl­imino­meth­yl)phenolate ligands. The dihedral angles between the benzene rings are 82.6 (2), 57.1 (2) and 62.9 (2)°. In the crystal, mol­ecules are linked by pairs of weak C—H⋯Br hydrogen bonds, forming inversion dimers. PMID:24454033

  19. 40 CFR 721.10556 - Poly(oxy-1,2-ethanediyl), .alpha.- (2-methyl-2-propen-1-yl) -.omega.-hydroxy-,C12-15-alkyl ethers.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Poly(oxy-1,2-ethanediyl), .alpha.- (2...-ethanediyl), .alpha.- (2-methyl-2-propen-1-yl) -.omega.-hydroxy-,C12-15-alkyl ethers. (a) Chemical substance...-ethanediyl), .alpha.- (2-methyl-2-propen-1-yl) -.omega.-hydroxy-,C12-15-alkyl ethers (PMN P-06-450; CAS...

  20. 40 CFR 721.10557 - Poly(oxy-1,2-ethanediyl), .alpha.- (2-methyl-2-propen-1-yl) -.omega.-hydroxy-,C10-16-alkyl ethers.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Poly(oxy-1,2-ethanediyl), .alpha.- (2...-ethanediyl), .alpha.- (2-methyl-2-propen-1-yl) -.omega.-hydroxy-,C10-16-alkyl ethers. (a) Chemical substance...-ethanediyl), .alpha.- (2-methyl-2-propen-1-yl) -.omega.-hydroxy-,C10-16-alkyl ethers (PMN P-06-451; CAS...

  1. 40 CFR 721.10556 - Poly(oxy-1,2-ethanediyl), .alpha.- (2-methyl-2-propen-1-yl) -.omega.-hydroxy-,C12-15-alkyl ethers.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Poly(oxy-1,2-ethanediyl), .alpha.- (2...-ethanediyl), .alpha.- (2-methyl-2-propen-1-yl) -.omega.-hydroxy-,C12-15-alkyl ethers. (a) Chemical substance...-ethanediyl), .alpha.- (2-methyl-2-propen-1-yl) -.omega.-hydroxy-,C12-15-alkyl ethers (PMN P-06-450; CAS...

  2. 40 CFR 721.10558 - Poly(oxy-1,2-ethanediyl), .alpha.- (2-methyl-2-propen-1-yl) -.omega.-hydroxy-,C12-16-alkyl ethers.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Poly(oxy-1,2-ethanediyl), .alpha.- (2...-ethanediyl), .alpha.- (2-methyl-2-propen-1-yl) -.omega.-hydroxy-,C12-16-alkyl ethers. (a) Chemical substance...-ethanediyl), .alpha.- (2-methyl-2-propen-1-yl) -.omega.-hydroxy-,C12-16-alkyl ethers (PMN P-06-452; CAS...

  3. 40 CFR 721.10557 - Poly(oxy-1,2-ethanediyl), .alpha.- (2-methyl-2-propen-1-yl) -.omega.-hydroxy-,C10-16-alkyl ethers.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Poly(oxy-1,2-ethanediyl), .alpha.- (2...-ethanediyl), .alpha.- (2-methyl-2-propen-1-yl) -.omega.-hydroxy-,C10-16-alkyl ethers. (a) Chemical substance...-ethanediyl), .alpha.- (2-methyl-2-propen-1-yl) -.omega.-hydroxy-,C10-16-alkyl ethers (PMN P-06-451; CAS...

  4. 40 CFR 721.10558 - Poly(oxy-1,2-ethanediyl), .alpha.- (2-methyl-2-propen-1-yl) -.omega.-hydroxy-,C12-16-alkyl ethers.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Poly(oxy-1,2-ethanediyl), .alpha.- (2...-ethanediyl), .alpha.- (2-methyl-2-propen-1-yl) -.omega.-hydroxy-,C12-16-alkyl ethers. (a) Chemical substance...-ethanediyl), .alpha.- (2-methyl-2-propen-1-yl) -.omega.-hydroxy-,C12-16-alkyl ethers (PMN P-06-452; CAS...

  5. Biosynthesis of rhodiocyanosides in Lotus japonicus: rhodiocyanoside A is synthesized from (Z)-2-methylbutanaloxime via 2-methyl-2-butenenitrile.

    PubMed

    Saito, Shigeki; Motawia, Mohammed Saddik; Olsen, Carl Erik; Møller, Birger Lindberg; Bak, Søren

    2012-05-01

    Lotus japonicus contains the two cyanogenic glucosides, linamarin and lotaustralin, and the non cyanogenic hydroxynitriles, rhodiocyanoside A and D, with rhodiocyanoside A as the major rhodiocyanoside. Rhodiocyanosides are structurally related to cyanogenic glucosides but are not cyanogenic. In vitro administration of intermediates of the lotaustralin pathway to microsomes prepared from selected L. japonicus accessions identified 2-methyl-2-butenenitrile as an intermediate in the rhodiocyanoside biosynthetic pathway. In vitro inhibitory studies with carbon monoxide and tetcyclacis indicate that the conversion of (Z)-2-methylbutanal oxime to 2-methyl-2-butenenitrile is catalyzed by cytochrome P450(s). Carbon monoxide inhibited cyanogenic glucosides as well as rhodiocyanosides synthesis, but inhibition of the latter pathway was much stronger. These results demonstrate that the cyanogenic glucoside and rhodiocyanosides pathways share CYP79Ds to obtain (Z)-2-methylbutanaloxime from l-isoleucine, whereas the subsequent conversions are catalyzed by different P450s. The aglycon of rhodiocyanoside A forms the cyclic product 3-methyl-2(5H)-furanone. Furanones are known to possess antimicrobial properties indicating that rhodiocyanoside A may have evolved to serve as a phytoanticipin that following β-glucosidase activation and cyclization of the aglycone formed, give rise to a potent defense compound. PMID:22385904

  6. SKA2 Methylation is associated with Decreased Prefrontal Cortical Thickness and Greater PTSD Severity among Trauma-Exposed Veterans

    PubMed Central

    Sadeh, Naomi; Spielberg, Jeffrey M.; Logue, Mark W.; Wolf, Erika J.; Smith, Alicia K.; Lusk, Joanna; Hayes, Jasmeet P.; Sperbeck, Emily; Milberg, William P.; McGlinchey, Regina E.; Salat, David H.; Carter, Weleetka C.; Stone, Annjanette; Schichman, Steven A.; Humphries, Donald E.; Miller, Mark W.

    2015-01-01

    Methylation of the SKA2 gene has recently been identified as a promising biomarker of suicide risk. Based on this finding, we examined associations between SKA2 methylation, cortical thickness, and psychiatric phenotypes linked to suicide in trauma-exposed veterans. 200 trauma-exposed white non-Hispanic veterans of the recent conflicts in Iraq and Afghanistan (91% male) underwent clinical assessment and had blood drawn for genotyping and methylation analysis. 145 participants also had neuroimaging data available. Based on previous research, we examined DNA methylation at the CpG locus cg13989295 as well as DNA methylation adjusted for genotype at the methylation-associated SNP (rs7208505) in relationship to whole-brain cortical thickness, posttraumatic stress disorder symptoms (PTSD), and depression symptoms. Whole-brain vertex-wise analyses identified three clusters in prefrontal cortex that were associated with genotype-adjusted SKA2 DNA methylation (methylationadj). Specifically, DNA methylationadj was associated with bilateral reductions of cortical thickness in frontal pole and superior frontal gyrus, and similar effects were found in the right orbitofrontal cortex and right inferior frontal gyrus. PTSD symptom severity was positively correlated with SKA2 DNA methylationadj and negatively correlated with cortical thickness in these regions. Mediation analyses showed a significant indirect effect of PTSD on cortical thickness via SKA2 methylation status. Results suggest that DNA methylationadj of SKA2 in blood indexes stress-related psychiatric phenotypes and neurobiology, pointing to its potential value as a biomarker of stress exposure and susceptibility. PMID:26324104

  7. Alumina-supported bimetallics of palladium alloyed with germanium, tin, lead, or antimony from organometallic precursors. II. Gas-phase hydrogenation of 2-methyl-1-buten-3-yne (valylene) and 2-methyl-1,3-butadiene (isoprene)

    SciTech Connect

    Aduriz, H.R.; Bodnariuk, P. ); Coq, B.; Figueras, F. )

    1991-05-01

    A series of PdGe, PdSb, PdSn, and PdPb/{alpha}{minus}Al{sub 2}O{sub 3} catalysts, prepared by the controlled surface reaction (CSR) technique from organometallic precursors have been tested in the gas-phase hydrogenation of 2-methyl-1-buten-3-yne (valylene) and 2-methyl-1,3-butadiene (isoprene). On catalysts reduced at 573 K, the turnover frequencies for valylene (TON{sub v}) and isoprene (TON{sub 1}) hydrogenation were not modified by addition to the 0.09wt% Pd/{alpha}{minus}Al{sub 2}O{sub 3} base catalyst of Ge, Sb, Sn, or Pb, up to0.1 wt% (at 293 K: TON{sub v}= 20 s{sup {minus}1} and TON{sub 1} = 33 s{sup {minus}1}). Pd/{alpha}{minus}Al{sub 2}O{sub 3} reduced at 773 K was severely sintered (d{sub TEM} increased from 2.8nm to 12.4nm) and TON{sub v} and TON{sub 1} at 293 K increased to 190 and 283 s{sup {minus}1}, respectively, as a result of an apparent crystal size effect: the reactants adsorb more strongly on the smaller Pd particles. Upon alloying with Ge, Sb, Sn, or Pb and a subsequent reduction at 773 K, a modest decrease of both TON{sub v} (by a factor of 2) and TON{sub 1} (by a factor of 2{minus}5) was observed. At high conversion, both the selectivity to isoprene (S{sub I}) in valylene hydrogenation, and to olefins (S{sub 0}) in isoprene hydrogenation on Pd/{alpha}{minus}Al{sub 2}O{sub 3} were improved upon alloying with Sb, Sn, or Pb (Ge had no effect). In addition, the isomerization of 2-methyl-1-butene and 3-methyl-1-butene (double bond migration reaction) during isoprene hydrogenation was partially suppressed on PdSn and PdPb/{alpha}{minus}Al{sub 2}O{sub 3}. The improvement in selectivities was interpreted in terms of a change in the relative adsorption strength of the reactants and intermediate products over the new bimetallic sites.

  8. N-Butyl-4-butyl­imino-2-methyl­pentan-2-aminium (E)-quercetinate

    PubMed Central

    Grosu, Ioana-Georgeta; Borodi, Gheorghe; Pop, Mihaela Maria

    2012-01-01

    The title salt, C14H31N2 +·C15H9O7 −, was obtained in the reaction of quercetin with n-butyl­amine in a mixture of acetone and hexane. The crystal structure determination shows that the quercetin donates one of its phenol H atoms to the N-butyl-4-butyl­imino-2-methyl­pentan-2-amine mol­ecule. The crystal structure of the salt is stabilized by intramolecular (N—H⋯N for the cation and O—H⋯O for the anion) and intermolecular hydrogen bonding (N—H⋯O between cation–anion pairs and O—H⋯O between anions). Quercetin molecules form dimers connected into a two-dimensional network. The dihedral angle between the quercetin ring systems is 19.61 (8)°. PMID:22904895

  9. Synthesis and characterization of a new photoluminescent material tris (2-methyl-8-hydroxy quinoline) lanthanum La(mq)3

    NASA Astrophysics Data System (ADS)

    Kumar, Rahul; Bhargava, Parag

    2016-05-01

    A new photoluminescence material, tris (2-methyl-8-hydroxy quinoline) lanthanum has been synthesized and characterized by different techniques. The prepared material La(mq)3 was characterized for structural, thermal and photoluminescence analysis. Structural analysis of this material was done by fourier transformed infrared spectroscopy (FTIR) and mass spectroscopy. Thermal analysis of this material was done by thermal gravimetric analysis (TGA) shows the thermal stability up to 400°C. Absorption and emission spectra of the material was measured by UV-visible spectroscopy and photoluminescence spectroscopy. Solution of this material La(mq)3 in ethanol showed absorption peak at 385nm respectively which may be attributed due to (π - π*) transitions. The photoluminescence spectra of La(mq)3 in ethanol solution showed intense peak at 430 nm.

  10. Densities and viscosities of solutions of monoethanolamine + N-Methyldiethanolamine + water and monoethanolamine + 2-amino-2-methyl-1-propanol + water

    SciTech Connect

    Li, M.H.; Lie, Y.C. . Dept. of Chemical Engineering)

    1994-07-01

    The densities and viscosities of aqueous mixtures of monoethanolamine (MEA) with N-methyldiethanolamine (MDEA) and MEA with 2-amino-2-methyl-1-propanol (AMP) have been studied at temperatures from 30 to 80 C. For density measurements, four MEA + MDEA (a total of 20 mass %) + H[sub 2]O mixtures and eight MEA + AMP (20 and 30 mass %) + H[sub 2]O mixtures were studied. For viscosity measurements, ten MEA + MDEA + H[sub 2]O mixtures and eight MEA + AMP + H[sub 2]O mixtures were measured. A Redlich-Kister equation of the excess volume was applied to represent the density of the liquid mixtures. The equation of Grunberg and Nissan of liquid viscosity was used to correlate the viscosity data. Both density and viscosity calculations show satisfactory results.

  11. Energy storage capacity of reversible liquid-phase Diels Alder reaction between maleic anhydride and 2- methyl furan

    SciTech Connect

    Sparks, B.G.; Poling, B.E.

    1983-07-01

    Calorimetry was used to determine the heat of reaction and equilibrium constant at 318 K for the reaction between maleic anhydride (A) and 2-methyl furan (B). The values were-60 kJ/gmol and 614 cm/sup 3//gmol, respectively. The motivation for this work was to find a single phase-reacting system that could be used to store solar energy. Thus, the energy storage capacity was calculated for a mixture of A and B, both initially at 7 kmol/m/sup 3/, in dioxane. The maximum apparent heat capacity of 7.37 J/cm/sup 3/ X K occurred at 334 K. This maximum value is 76% higher than the heat capacity of pure water.

  12. Substituent effects in heterogeneous catalysis. VIII. Reactions of 2-methyl- and 2-ethylcyclohexanone with deuterium catalyzed by platinum metals

    SciTech Connect

    Teratani, S.; Tanaka, K.; Ogawa, H.; Taya, K.

    1981-08-01

    2-Methyl and 2-ethyl derivatives of cyclohexanone were allowed to react with deuterium in t-BuOD using platinum group metals as catalysts. The product alcohols and the remaining ketone were examined by mass spectrometry. Over Ru, Os, and Ir, the simple addition of two deuterium atoms to the carbonyl linkage was predominant, accompanied by little isotopic exchange. Over Pt, however, isotopic exchange was significant and over Rh and Pd quite extensive. The samples obtained over Rh and Pd were further analyzed by NMR spectroscopy to determine the loci of the incorporated deuterium atoms. Deuterium exchange over Pd was almost entirely confined to the C(2) and C(6) positions, while that over Rh was smeared beyond these positions. These results can be accounted for by assuming the intermediacy of ..pi..-absorbed ..pi..-oxaallylic species on Pd and of ..beta..-diadsorbed species on Rh.

  13. Engineering an isoprenoid pathway in Escherichia coli for production of 2-methyl-3-buten-2-ol: a potential biofuel.

    PubMed

    Gupta, Dinesh; Summers, Michael L; Basu, Chhandak

    2014-06-01

    2-Methyl-3-buten-2-ol (MBO) is a natural volatile 5-carbon alcohol produced by several pine species that have the potential to be used as biofuel. MBO has a high energy content making it superior to ethanol in terms of energy output, and due to its volatility and lower solubility in water, MBO is easier to recover than ethanol. Pine's MBO synthase enzyme utilizes the intermediate dimethylallyl pyrophosphate (DMAPP) produced by the methyl-erythritol-4-phosphate isoprenoid pathway for the production of MBO. In this study, we performed metabolic engineering of Escherichia coli to express an alternate mevalonate dependent pathway for production of DMAPP, along with a codon optimized Pinus sabiniana MBO synthase gene. This heterologous expressed pathway carried out the conversion of an acetyl CoA precursor to DMAPP leading to production of MBO. PMID:24271564

  14. SKA2 methylation is associated with decreased prefrontal cortical thickness and greater PTSD severity among trauma-exposed veterans.

    PubMed

    Sadeh, N; Spielberg, J M; Logue, M W; Wolf, E J; Smith, A K; Lusk, J; Hayes, J P; Sperbeck, E; Milberg, W P; McGlinchey, R E; Salat, D H; Carter, W C; Stone, A; Schichman, S A; Humphries, D E; Miller, M W

    2016-03-01

    Methylation of the SKA2 (spindle and kinetochore-associated complex subunit 2) gene has recently been identified as a promising biomarker of suicide risk. Based on this finding, we examined associations between SKA2 methylation, cortical thickness and psychiatric phenotypes linked to suicide in trauma-exposed veterans. About 200 trauma-exposed white non-Hispanic veterans of the recent conflicts in Iraq and Afghanistan (91% male) underwent clinical assessment and had blood drawn for genotyping and methylation analysis. Of all, 145 participants also had neuroimaging data available. Based on previous research, we examined DNA methylation at the cytosine-guanine locus cg13989295 as well as DNA methylation adjusted for genotype at the methylation-associated single nucleotide polymorphism (rs7208505) in relationship to whole-brain cortical thickness, posttraumatic stress disorder symptoms (PTSD) and depression symptoms. Whole-brain vertex-wise analyses identified three clusters in prefrontal cortex that were associated with genotype-adjusted SKA2 DNA methylation (methylationadj). Specifically, DNA methylationadj was associated with bilateral reductions of cortical thickness in frontal pole and superior frontal gyrus, and similar effects were found in the right orbitofrontal cortex and right inferior frontal gyrus. PTSD symptom severity was positively correlated with SKA2 DNA methylationadj and negatively correlated with cortical thickness in these regions. Mediation analyses showed a significant indirect effect of PTSD on cortical thickness via SKA2 methylation status. Results suggest that DNA methylationadj of SKA2 in blood indexes stress-related psychiatric phenotypes and neurobiology, pointing to its potential value as a biomarker of stress exposure and susceptibility. PMID:26324104

  15. Structure–Activity Relationships Comparing N-(6-Methylpyridin-yl)-Substituted Aryl Amides to 2-Methyl-6-(substituted-arylethynyl)pyridines or 2-Methyl-4-(substituted-arylethynyl)thiazoles as Novel Metabotropic Glutamate Receptor Subtype 5 Antagonists†

    PubMed Central

    Kulkarni, Santosh S.; Zou, Mu-Fa; Cao, Jianjing; Deschamps, Jeffrey R.; Rodriguez, Alice L.; Conn, P. Jeffrey; Newman, Amy Hauck

    2010-01-01

    The metabotropic glutamate receptor subtype 5 (mGluR5) has been implicated in anxiety, depression, pain, mental retardation, and addiction. The potent and selective noncompetitive mGluR5 antagonist 2-methyl-6-(phenylethynyl)pyridine (MPEP, 1) has been a critically important tool used to further elucidate the role of mGluR5 in these CNS disorders. In an effort to provide novel and structurally diverse selective mGluR5 antagonists, we previously described a set of analogues with moderate activity wherein the alkyne bond was replaced with an amide group. In the present report, extended series of both amide and alkyne-based ligands were synthesized. MGluR5 binding and functional data were obtained that identified (1) several novel alkynes with comparable affinities to 1 at mGluR5 (e.g., 10 and 20–23), but (2) most structural variations to the amide template were not well tolerated, although a few potent amides were discovered (e.g., 55 and 56). Several of these novel analogues show drug-like physical properties (e.g., cLogP range) 2–5) that support their use for in vivo investigation into the role of mGluR5 in CNS disorders. PMID:19445453

  16. 2-Methyl-3-furanthiol and methional are possible off-flavors in stored orange juice: aroma-similarity, NIF/SNIF GC-O, and GC analyses.

    PubMed

    Bezman, Y; Rouseff, R L; Naim, M

    2001-11-01

    The occurrence of methional in fresh orange juice, and possible occurrence of beta-damascenone in heated orange juice, has been previously suggested. Here we report on the occurrence of 2-methyl-3-furanthiol in the headspace, collected by solid-phase micro-extraction, of fresh, pasteurized, and stored orange juice. The contents of 2-methyl-3-furanthiol and methional were quantified, and the relative level of beta-damascenone was estimated, in the headspace of fresh, pasteurized, and stored orange juices using the nasal impact frequency (NIF) and surface of NIF (SNIF) GC-Olfactometry procedure. 2-Methyl-3-furanthiol concentrations were 2 ng/L in fresh and pasteurized Shamuti orange juice, and 270 ng/L in stored juice of the same variety. Methional concentrations were 550, 830, and 11,550 ng/L in fresh, pasteurized, and stored pasteurized juices, respectively. beta-Damascenone content appeared to have increased during pasteurization and storage. Aroma-similarity experiments strongly suggest that 2-methyl-3-furanthiol and methional, at the levels found in stored orange juice (21 days at 35 degrees C), contribute to stored orange juice off-flavor. PMID:11714338

  17. SOA Formation from the Atmospheric Oxidation of 2-Methyl-3-Buten-2-ol and Its Implications for PM2.5

    EPA Science Inventory

    The formation of secondary organic aerosol (SOA) generated by irradiating 2-methyl-3-buten-2-01 (MBO) in the presence and/or absence of NOx H2O2, and/or SO2 was examined. Experiments were conducted. in smog chambers operated either in dyna....

  18. EMISSION OF 2-METHYL-3-BUTEN-2-OL BY PINES: A POTENTIALLY LARGE NATURAL SOURCE OF REACTIVE CARBON TO THE ATMOSPHERE

    EPA Science Inventory

    High rates of emission of 2-methyl-3-buten-2-ol (MBO) were measured from needles of several pine species. Emissions of MBO in the light were 1 to 2 orders of magnitude higher than emissions of monoterpenes and, in contrast to monoterpene emissions from pines, were absent in the d...

  19. 75 FR 770 - Acrylic acid-benzyl methacrylate-1-propanesulfonic acid, 2-methyl-2-[(1-oxo-2-propenyl)amino...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-01-06

    ... Findings In the Federal Register of October 7, 2009 (74 FR 51600) (FRL-8792- 7), EPA issued a notice..., entitled Regulatory Planning and Review (58 FR 51735, October 4, 1993). Because this final rule has been... FR 28355, May 22, 2001) or Executive Order 13045, entitled Protection of Children from...

  20. Treatment of taste and odor causing compounds 2-methyl isoborneol and geosmin in drinking water: a critical review.

    PubMed

    Srinivasan, Rangesh; Sorial, George A

    2011-01-01

    Problems due to the taste and odor in drinking water are common in treatment facilities around the world. Taste and odor are perceived by the public as the primary indicators of the safely and acceptability of drinking water and are mainly caused by the presence of two semi-volatile compounds--2-methyl isoborneol (MIB) and geosmin. A review of these two taste and odor causing compounds in drinking water is presented. The sources for the formation of these compounds in water are discussed along with the health and regulatory implications. The recent developments in the analysis of MIB/geosmin in water which have allowed for rapid measurements in the nanogram per liter concentrations are also discussed. This review focuses on the relevant treatment alternatives, that are described in detail with emphasis on their respective advantages and problems associated with their implementation in a full-scale facility. Conventional treatment processes in water treatment plants, such as coagulation, sedimentation and chlorination have been found to be ineffective for removal of MIB/geosmin. Studies have shown powdered activated carbon, ozonation and biofiltration to be effective in treatment of these two compounds. Although some of these technologies are more effective and show more promise than the others, much work remains to be done to optimize these technologies so that they can be retrofitted or installed with minimal impact on the overall operation and effectiveness of the treatment system. PMID:21476334

  1. Polycyclic aromatic hydrocarbons are associated with insulin receptor substrate 2 methylation in adipose tissues of Korean women.

    PubMed

    Kim, Young Hun; Lee, Yoon Soon; Lee, Duk Hee; Kim, Dong Sun

    2016-10-01

    Polycyclic aromatic hydrocarbons (PAHs) are highly lipid soluble and are an increasing concern for general populations given their various adverse health effects, including obesity-related metabolic dysfunction. DNA methylation can act as a downstream effector for the biological effects of environmental exposures, but whether PAHs influence DNA methylation is unclear. To test for possible adverse effects of PAHs on adipose tissue (AT), we determined the promoter methylation status of 12 genes involved in glucose and lipid metabolism (CS, GLUT4, IR, IRS1, IRS2, LIPIN1, MCAD, PCK1, PCK2, PPARGC1Β, SDHA, and SREBP1) in visceral AT of Korean women by using methylation-specific PCR (MSP). IRS2 methylation alone was significantly associated with concentrations of individual PAH chemicals. When the PAH summary measure was used, the odds ratios of IRS2 hypermethylation across quartile of the PAH summary measure were 1, 1.7, 2.0, and 11.2 (95% confidence interval: 1.5-84.0) after adjusting for age and BMI (P trend=0.02). The strength of association between PAH summary measure and IRS2 hypermethylation was as similar as that of BMI. Collectively, these results suggested that lipophilic PAHs might be contributing factors to the pathogenesis of insulin resistance through methylation-mediated suppression of the IRS2 gene. However, further studies with large sample size are needed to confirm our findings. PMID:27236571

  2. 2-Methyl-3-buten-2-ol (MBO) synthase expression in Nostoc punctiforme leads to over production of phytols

    PubMed Central

    Gupta, Dinesh; Ip, Tina; Summers, Michael L; Basu, Chhandak

    2015-01-01

    Phytol is a diterpene alcohol of medicinal importance and it also has potential to be used as biofuel. We found over production of phytol in Nostoc punctiforme by expressing a 2-Methyl-3-buten-2-ol (MBO) synthase gene. MBO synthase catalyzes the conversion of dimethylallyl pyrophosphate (DMAPP) into MBO, a volatile hemiterpene alcohol, in Pinus sabiniana. The result of enhanced phytol production in N. punctiforme, instead of MBO, could be explained by one of the 2 models: either the presence of a native prenyltransferase enzyme with a broad substrate specificity, or appropriation of a MBO synthase metabolic intermediate by a native geranyl diphosphate (GDP) synthase. In this work, an expression vector with an indigenous petE promoter for gene expression in the cyanobacterium N. punctiforme was constructed and MBO synthase gene expression was successfully shown using reverse transcriptase (RT)-PCR and SDS-PAGE. Gas chromatography – mass spectrophotometry (GC-MS) was performed to confirm phytol production from the transgenic N. punctiforme strains. We conclude that the expression of MBO synthase in N. punctiforme leads to overproduction of an economically important compound, phytol. This study provides insights about metabolic channeling of isoprenoids in cyanobacteria and also illustrates the challenges of bioengineering non-native hosts to produce economically important compounds. PMID:25424521

  3. Synthesis and cytotoxic activity of N-((2-methyl-4(3H)-quinazolinon-6-yl)methyl)dithiocarbamates.

    PubMed

    Cao, Sheng-Li; Wang, Yao; Zhu, Lin; Liao, Ji; Guo, Yan-Wen; Chen, Lin-Lin; Liu, Hong-Qin; Xu, Xingzhi

    2010-09-01

    A series of N-((2-methyl-4(3H)-quinazolinon-6-yl)methyl)dithiocarbamates 5a-w were synthesized and evaluated for their cytotoxic activity against five human cancer cell lines. We found that compound 5k inhibited proliferation of A549, MCF-7, HeLa, HT29 and HCT-116 cells with IC(50) values of 5.44, 7.15, 12.16, 10.35 and 11.44 microM, respectively. Compound 5i was the most potent with an IC(50) value of 3.65 microM against proliferation of MCF-7 cells, while 5n was the most potent with an IC(50) value of 5.09 microM against proliferation of A549 cells. Cell cycle analysis showed that both 5i and 5k arrested A549 cells at S and G2/M phases, suggesting that these compounds act through mechanisms different from 5-fluorouracil, which arrests cells at S phase only. PMID:20538385

  4. Fungal Symbionts of the Spruce Bark Beetle Synthesize the Beetle Aggregation Pheromone 2-Methyl-3-buten-2-ol.

    PubMed

    Zhao, Tao; Axelsson, Karolin; Krokene, Paal; Borg-Karlson, Anna-Karin

    2015-09-01

    Tree-killing bark beetles depend on aggregation pheromones to mass-attack their host trees and overwhelm their resistance. The beetles are always associated with phytopathogenic ophiostomatoid fungi that probably assist in breaking down tree resistance, but little is known about if or how much these fungal symbionts contribute to the beetles' aggregation behavior. In this study, we determined the ability of four major fungal symbionts of the spruce bark beetle Ips typographus to produce beetle aggregation pheromones. The fungi were incubated on Norway spruce Picea abies bark, malt agar, or malt agar amended with 0.5% (13)C glucose. Volatiles present in the headspace of each fungus were analyzed for 7 days after incubation using a SPME autosampler coupled to a GC/MS. Two Grosmannia species (G. penicillata and G. europhioides) produced large amounts of 2-methyl-3-buten-2-ol (MB), the major component in the beetles' aggregation pheromone blend, when growing on spruce bark or malt agar. Grosmannia europhioides also incorporated (13)C glucose into MB, demonstrating that the fungi can synthesize MB de novo using glucose as a carbon source. This is the first clear evidence that fungal symbionts of bark beetles can produce components in the aggregation pheromone blend of their beetle vectors. This provides new insight into the possible ecological roles of fungal symbionts in bark beetle systems and may deepen our understanding of species interactions and coevolution in these important biological systems. PMID:26302987

  5. LETTER TO THE EDITOR: Characteristics of the terahertz radiation from single crystals of N-substituted 2-methyl-4-nitroaniline

    NASA Astrophysics Data System (ADS)

    Hashimoto, Hideki; Takahashi, Hironori; Yamada, Takashi; Kuroyanagi, Kazuyoshi; Kobayashi, Takayoshi

    2001-06-01

    Terahertz (THz) radiation was generated via optical rectification from organic single crystals, i.e. N-substituted (N-benzyl, N-diphenylmethyl, and N-2-naphthylmethyl) derivatives of 2-methyl-4-nitroaniline (MNA), and it was detected by means of the electro-optic sampling method. The intensity and the spectrum of the THz radiation were compared with those of ZnTe and DAST (N, N-dimethylamino-N'-methylstilbazolium p-toluenesulphonate) crystals. The integrated intensity of the THz radiation from the N-benzyl-MNA crystal was two thirds of that for the ZnTe crystal, the best-known practical THz emitter, and was as intense as that for the DAST crystal, the best organic THz emitter ever studied. The spectrum of the ZnTe crystal extended to 3 THz, while that of the N-benzyl MNA and DAST crystals dropped off around 2.5 THz. The THz radiation intensities from all of the organic crystals were compared quantitatively, on the basis of the consideration of molecular arrangements in the crystals. It was suggested that the absorption due to low-frequency phonon modes affected both the intensity and the spectral band shape of the THz radiation.

  6. 2-Methyl-3-buten-2-ol (MBO) synthase expression in Nostoc punctiforme leads to over production of phytols.

    PubMed

    Gupta, Dinesh; Ip, Tina; Summers, Michael L; Basu, Chhandak

    2015-01-01

    Phytol is a diterpene alcohol of medicinal importance and it also has potential to be used as biofuel. We found over production of phytol in Nostoc punctiforme by expressing a 2-Methyl-3-buten-2-ol (MBO) synthase gene. MBO synthase catalyzes the conversion of dimethylallyl pyrophosphate (DMAPP) into MBO, a volatile hemiterpene alcohol, in Pinus sabiniana. The result of enhanced phytol production in N. punctiforme, instead of MBO, could be explained by one of the 2 models: either the presence of a native prenyltransferase enzyme with a broad substrate specificity, or appropriation of a MBO synthase metabolic intermediate by a native geranyl diphosphate (GDP) synthase. In this work, an expression vector with an indigenous petE promoter for gene expression in the cyanobacterium N. punctiforme was constructed and MBO synthase gene expression was successfully shown using reverse transcriptase (RT)-PCR and SDS-PAGE. Gas chromatography--mass spectrophotometry (GC-MS) was performed to confirm phytol production from the transgenic N. punctiforme strains. We conclude that the expression of MBO synthase in N. punctiforme leads to overproduction of an economically important compound, phytol. This study provides insights about metabolic channeling of isoprenoids in cyanobacteria and also illustrates the challenges of bioengineering non-native hosts to produce economically important compounds. PMID:25424521

  7. Atomic resolution experimental phase information reveals extensive disorder and bound 2-methyl-2,4-pentanediol in Ca(2+)-calmodulin.

    PubMed

    Lin, Jiusheng; van den Bedem, Henry; Brunger, Axel T; Wilson, Mark A

    2016-01-01

    Calmodulin (CaM) is the primary calcium signaling protein in eukaryotes and has been extensively studied using various biophysical techniques. Prior crystal structures have noted the presence of ambiguous electron density in both hydrophobic binding pockets of Ca(2+)-CaM, but no assignment of these features has been made. In addition, Ca(2+)-CaM samples many conformational substates in the crystal and accurately modeling the full range of this functionally important disorder is challenging. In order to characterize these features in a minimally biased manner, a 1.0 Å resolution single-wavelength anomalous diffraction data set was measured for selenomethionine-substituted Ca(2+)-CaM. Density-modified electron-density maps enabled the accurate assignment of Ca(2+)-CaM main-chain and side-chain disorder. These experimental maps also substantiate complex disorder models that were automatically built using low-contour features of model-phased electron density. Furthermore, experimental electron-density maps reveal that 2-methyl-2,4-pentanediol (MPD) is present in the C-terminal domain, mediates a lattice contact between N-terminal domains and may occupy the N-terminal binding pocket. The majority of the crystal structures of target-free Ca(2+)-CaM have been derived from crystals grown using MPD as a precipitant, and thus MPD is likely to be bound in functionally critical regions of Ca(2+)-CaM in most of these structures. The adventitious binding of MPD helps to explain differences between the Ca(2+)-CaM crystal and solution structures and is likely to favor more open conformations of the EF-hands in the crystal. PMID:26894537

  8. Canopy level emissions of 2-methyl-3-buten-2-ol, monoterpenes, and sesquiterpenes from an experimental Pinus taeda plantation.

    PubMed

    Geron, Christopher D; Daly, Ryan W; Arnts, Robert R; Guenther, Alex B; Mowry, Fred L

    2016-09-15

    Emissions of Biogenic Volatile Organic Compounds (BVOCs) observed during 2007 from an experimental Pinus taeda plantation in Central North Carolina are compared with model estimates from the Model of Emissions of Gases and Aerosols from Nature (MEGAN) version 2.1. Relaxed eddy accumulation (REA) estimates of 2-methyl-3-buten-2-ol (MBO) fluxes are a factor of 3-4 higher than MEGAN estimates. MEGAN monoterpene emission estimates were a factor of approximately two higher than REA flux measurements. MEGAN β-caryophyllene emission estimates were within 60% of growing season REA flux estimates but were several times higher than REA fluxes during cooler, dormant season periods. The sum of other sesquiterpene emissions estimated by MEGAN was several times higher than REA estimates throughout the year. Model components are examined to understand these discrepancies. Measured summertime leaf area index (LAI) (and therefore foliar biomass) is a factor of two higher than assumed in MEGAN for the P. taeda default. Increasing the canopy mean MBO emission factor from 0.35 to 1.0mgm(-2)h(-1) also reduces MEGAN vs. REA flux differences. This increase is within current MBO emission factor uncertainties. The algorithm within MEGAN which adjusts isoprene emission estimates as a function of the temperature and light of the previous 24h seems also to improve the seasonal MEGAN MBO correlation with REA fluxes. Including the effects of the previous 240h, however, seems to degrade temporal model correlation with fluxes. Monoterpene and sesquiterpene composition data from the REA are compared with MEGAN2.1 estimates and also branch enclosure and needle extract data collected at this site. To our knowledge, the flux data presented here are the first reported for MBO and sesquiterpenes from a P. taeda ecosystem. PMID:27232720

  9. N-(2-methyl-indol-1H-5-yl)-1-naphthalenesulfonamide: A novel reversible antimitotic agent inhibiting cancer cell motility.

    PubMed

    Aceves-Luquero, Clara; Galiana-Roselló, Cristina; Ramis, Guillem; Villalonga-Planells, Ruth; García-España, Enrique; Fernández de Mattos, Silvia; Peláez, Rafael; Llinares, José M; González-Rosende, M Eugenia; Villalonga, Priam

    2016-09-01

    A series of compounds containing the sulfonamide scaffold were synthesized and screened for their in vitro anticancer activity against a representative panel of human cancer cell lines, leading to the identification of N-(2-methyl-1H-indol-5-yl)-1-naphthalenesulfonamide (8e) as a compound showing a remarkable activity across the panel, with IC50 values in the nanomolar-to-low micromolar range. Cell cycle distribution analysis revealed that 8e promoted a severe G2/M arrest, which was followed by cellular senescence as indicated by the detection of senescence-associated β-galactosidase (SA-β-gal) in 8e-treated cells. Prolonged 8e treatment also led to the onset of apoptosis, in correlation with the detection of increased Caspase 3/7 activities. Despite increasing γ-H2A.X levels, a well-established readout for DNA double-strand breaks, in vitro DNA binding studies with 8e did not support interaction with DNA. In agreement with this, 8e failed to activate the cellular DNA damage checkpoint. Importantly, tubulin staining showed that 8e promoted a severe disorganization of microtubules and mitotic spindle formation was not detected in 8e-treated cells. Accordingly, 8e inhibited tubulin polymerization in vitro in a dose-dependent manner and was also able to robustly inhibit cancer cell motility. Docking analysis revealed a compatible interaction with the colchicine-binding site of tubulin. Remarkably, these cellular effects were reversible since disruption of treatment resulted in the reorganization of microtubules, cell cycle re-entry and loss of senescent markers. Collectively, our data suggest that this compound may be a promising new anticancer agent capable of both reducing cancer cell growth and motility. PMID:27349984

  10. A high temperature and atmospheric pressure experimental and detailed chemical kinetic modelling study of 2-methyl furan oxidation

    PubMed Central

    Somers, Kieran P.; Simmie, John M.; Gillespie, Fiona; Burke, Ultan; Connolly, Jessica; Metcalfe, Wayne K.; Battin-Leclerc, Frédérique; Dirrenberger, Patricia; Herbinet, Olivier; Glaude, Pierre-Alexandre; Curran, Henry J.

    2013-01-01

    An experimental ignition delay time study for the promising biofuel 2-methyl furan (2MF) was performed at equivalence ratios of 0.5, 1.0 and 2.0 for mixtures of 1% fuel in argon in the temperature range 1200–1800 K at atmospheric pressure. Laminar burning velocities were determined using the heat-flux method for mixtures of 2MF in air at equivalence ratios of 0.55–1.65, initial temperatures of 298–398 K and atmospheric pressure. A detailed chemical kinetic mechanism consisting of 2059 reactions and 391 species has been constructed to describe the oxidation of 2MF and is used to simulate experiment. Accurate reproduction of the experimental data has been obtained over all conditions with the developed mechanism. Rate of production and sensitivity analyses have been carried out to identify important consumption pathways of the fuel and key kinetic parameters under these conditions. The reactions of hydrogen atom with the fuel are highlighted as important under all experimental conditions studied, with abstraction by the hydrogen atom promoting reactivity and hydrogen atom addition to the furan ring inhibiting reactivity. This work, to the authors knowledge, is the first to combine theoretical and experimental work to describe the oxidation of any of the alkylated furans. The mechanism developed herein to describe 2MF combustion should also function as a sub-mechanism to describe the oxidation of 2,5-dimethyl furan whilst also providing key insights into the oxidation of this similar biofuel candidate. PMID:23814505

  11. Photooxidation of 2-methyl-3-Buten-2-ol (MBO) as a potential source of secondary organic aerosol.

    PubMed

    Chan, Arthur W H; Galloway, Melissa M; Kwan, Alan J; Chhabra, Puneet S; Keutsch, Frank N; Wennberg, Paul O; Flagan, Richard C; Seinfeld, John H

    2009-07-01

    2-Methyl-3-buten-2-ol (MBO) is an important biogenic hydrocarbon emitted in large quantities by pine forests. Atmospheric photooxidation of MBO is known to lead to oxygenated compounds, such as glycolaldehyde, which is the precursor to glyoxal. Recent studies have shown that the reactive uptake of glyoxal onto aqueous particles can lead to formation of secondary organic aerosol (SOA). In this work, MBO photooxidation under high- and low-NO(x) conditions was performed in dual laboratory chambers to quantify the yield of glyoxal and investigate the potential for SOA formation. The yields of glycolaldehyde and 2-hydroxy-2-methylpropanal (HMPR), fragmentation products of MBO photooxidation, were observed to be lower at lower NO(x) concentrations. Overall, the glyoxal yield from MBO photooxidation was 25% under high-NO(x) and 4% under low-NO(x) conditions. In the presence of wet ammonium sulfate seed and under high-NO(x) conditions, glyoxal uptake and SOA formation were not observed conclusively, due to relatively low (< 30 ppb) glyoxal concentrations. Slight aerosol formation was observed under low-NO(x) and dry conditions, with aerosol mass yields on the order of 0.1%. The small amount of SOA was not related to glyoxal uptake, but is likely a result of reactions similar to those that generate isoprene SOA under low-NO(x) conditions. The difference in aerosol yields between MBO and isoprene photooxidation under low-NO(x) conditions is consistent with the difference in vapor pressures between triols (from MBO) and tetrols (from isoprene). Despite its structural similarity to isoprene, photooxidation of MBO is not expected to make a significant contribution to SOA formation. PMID:19673246

  12. Poly[(μ2-2-hydr­oxy-2-methyl­propionato-κ3 O 1,O 2:O 1′)(μ2-2-hydr­oxy-2-methyl­propionato-κ2 O 1:κO 1′)dioxido­uranium(VI)

    PubMed Central

    Yoshimura, Takashi; Kikunaga, Hidetoshi; Shinohara, Atsushi

    2009-01-01

    In the title compound, [UO2(C4H7O3)2]n, the dioxouranium(VI) units are linked by 2-hydr­oxy-2-methyl­propionate ligands into a honeycomb structure. The U atom is seven-coordinate in a penta­gonal-bipyramidal geometry. The uncoordinated hydr­oxy groups of the 2-hydr­oxy-2-methyl­propionate ions inter­act with the O atom of the uranyl and with the coordinated hydr­oxy group of an adjacent 2-hydr­oxy-2-methyl­propionate ion through O—H⋯O hydrogen bonds. PMID:21582314

  13. 1-(2‧-Aminophenyl)- and 1-(2‧-hydroxyphenyl)-2-methyl-4-nitroimidazole: Crystallizing with two molecules in the asymmetric unit

    NASA Astrophysics Data System (ADS)

    Kubicki, Maciej; Wagner, Paweł

    2008-03-01

    Two similar 4-nitroimidazole derivatives, 1-(2'-aminophenyl)-2-methyl-4-nitroimidazole, C 10H 9N 3O 3, and 1-(2'-hydroxyphenyl)-2-methyl-4-nitroimidazole, C 10H 10N 4O 2, crystallize with two molecules in the asymmetric unit ( Z' = 2). Packing conflicts may result from tendency towards closing hydrogen-bonded rings (dimer for amino-, and tetramer for hydroxy-derivative) and molecular stacking. These conflicts are solved in different ways in both compounds, due to the different nature of 2'-substituents, but in both cases the crystal structure involves multiple molecules in the asymmetry unit. The geometrical features of symmetry-independent molecules are similar. The nitro group is almost coplanar with the imidazole plane in amino derivative while it is significantly twisted in hydroxy-one.

  14. 2-Methyl-6-(phenylethynyl) pyridine (MPEP) reverses maze learning and PSD-95 deficits in Fmr1 knock-out mice

    PubMed Central

    Gandhi, Réno M.; Kogan, Cary S.; Messier, Claude

    2014-01-01

    Fragile X Syndrome (FXS) is caused by the lack of expression of the fragile X mental retardation protein (FMRP), which results in intellectual disability and other debilitating symptoms including impairment of visual-spatial functioning. FXS is the only single-gene disorder that is highly co-morbid with autism spectrum disorder and can therefore provide insight into its pathophysiology. Lack of FMRP results in altered group I metabotropic glutamate receptor (mGluR) signaling, which is a target for putative treatments. The Hebb-Williams (H-W) mazes are a set of increasingly complex spatial navigation problems that depend on intact hippocampal and thus mGluR-5 functioning. In the present investigation, we examined whether an antagonist of mGluR-5 would reverse previously described behavioral deficits in fragile X mental retardation 1 knock-out (Fmr1 KO) mice. Mice were trained on a subset of the H-W mazes and then treated with either 20 mg/kg of an mGluR-5 antagonist, 2-Methyl-6-(phenylethynyl) pyridine (MPEP; n = 11) or an equivalent dose of saline (n = 11) prior to running test mazes. Latency and errors were dependent variables recorded during the test phase. Immediately after completing each test, marble-burying behavior was assessed, which confirmed that the drug treatment was pharmacologically active during maze learning. Although latency was not statistically different between the groups, MPEP treated Fmr1 KO mice made significantly fewer errors on mazes deemed more difficult suggesting a reversal of the behavioral deficit. MPEP treated mice were also less perseverative and impulsive when navigating mazes. Furthermore, MPEP treatment reversed post-synaptic density-95 (PSD-95) protein deficits in Fmr1 KO treated mice, whereas levels of a control protein (β-tubulin) remained unchanged. These data further validate MPEP as a potentially beneficial treatment for FXS. Our findings also suggest that adapted H-W mazes may be a useful tool to document alterations in

  15. Murine T cell activation is regulated by surfen (bis-2-methyl-4-amino-quinolyl-6-carbamide)

    SciTech Connect

    Warford, Jordan; Doucette, Carolyn D.; Hoskin, David W.; Easton, Alexander S.

    2014-01-10

    Highlights: •Surfen is the first inhibitor of glycosaminoglycan function to be studied in murine T cells. •Surfen reduces T cell proliferation stimulated in vitro and in vivo. •Surfen reduces CD25 expression in T cells activated in vivo but not in vitro. •Surfen increases T cell proliferation when T cell receptor activation is bypassed. •Surfen’s effects are blocked by co-administration of heparin sulfate. -- Abstract: Surfen (bis-2-methyl-4-amino-quinolyl-6-carbamide) binds to glycosaminoglycans (GAGs) and has been shown to influence their function, and the function of proteoglycans (complexes of GAGs linked to a core protein). T cells synthesize, secrete and express GAGs and proteoglycans which are involved in several aspects of T cell function. However, there are as yet no studies on the effect of GAG-binding agents such as surfen on T cell function. In this study, surfen was found to influence murine T cell activation. Doses between 2.5 and 20 μM produced a graduated reduction in the proliferation of T cells activated with anti-CD3/CD28 antibody-coated T cell expander beads. Surfen (20 mg/kg) was also administered to mice treated with anti-CD3 antibody to activate T cells in vivo. Lymphocytes from surfen-treated mice also showed reduced proliferation and lymph node cell counts were reduced. Surfen reduced labeling with a cell viability marker (7-ADD) but to a much lower extent than its effect on proliferation. Surfen also reduced CD25 (the α-subunit of the interleukin (IL)-2 receptor) expression with no effect on CD69 expression in T cells treated in vivo but not in vitro. When receptor activation was bypassed by treating T cells in vitro with phorbyl myristate acetate (10 ng/ml) and ionomycin (100 ng/ml), surfen treatment either increased proliferation (10 μM) or had no effect (2.5, 5 and 20 μM). In vitro treatment of T cells with surfen had no effect on IL-2 or interferon-γ synthesis and did not alter proliferation of the IL-2 dependent cell

  16. Cloning, molecular characterization and functional analysis of 1-hydroxy-2-methyl-2-(E)-butenyl-4-diphosphate reductase (HDR) gene for diterpenoid tanshinone biosynthesis in Salvia miltiorrhiza Bge. f. alba.

    PubMed

    Hao, Gangping; Shi, Renjiu; Tao, Ru; Fang, Qian; Jiang, Xingyu; Ji, Haiwei; Feng, Lei; Huang, Luqi

    2013-09-01

    The enzyme 1-hydroxy-2-methyl-2-(E)-butenyl-4-diphosphate reductase (HDR) is a terminal-acting enzyme in the plastid MEP pathway, which produce isoprenoid precursors. The full-length cDNA of HDR, designated SmHDR1 (Genbank Accession No. JX516088), was isolated for the first time from Salvia miltiorrhiza Bge. f. alba. SmHDR1 contains a 1389-bp open reading frame encoding 463 amino acids. The deduced SmHDR1 protein, which shows high identity to HDRs of other plant species, is predicted to possess a chloroplast transit peptide at the N-terminus and four conserved cysteine residues. Transcription pattern analysis revealed that SmHDR1 has high levels of transcription in leaves and low levels of transcription in roots and stems. The expression of SmHDR1 was induced by 0.1 mM methyl-jasmonate (MeJA) and salicylic acid (SA), but not by 0.1 mM abscisic acid (ABA), in the hairy roots of S. miltiorrhiza Bge. f. alba. Complementation of SmHDR1 in the Escherichia coli HDR mutant MG1655 ara < > ispH demonstrated the function of this enzyme. A functional color assay in E. coli showed that SmHDR1 accelerates the biosynthesis of β-carotene, indicating that SmHDR1 encodes a functional protein. Overexpression of SmHDR1 enhanced the production of tanshinones in cultured hairy roots of S. miltiorrhiza Bge. f. alba. These results indicate that SmHDR1 is a novel and important enzyme involved in the biosynthesis of diterpenoid tanshinones in S. miltiorrhiza Bge. f. alba. PMID:23770591

  17. Synthesis, characterization, and tyrosinase biomimetic catalytic activity of copper(II) complexes with schiff base ligands derived from α-diketones with 2-methyl-3-amino-(3 H)-quinazolin-4-one

    NASA Astrophysics Data System (ADS)

    Ramadan, Abd El-Motaleb M.; Ibrahim, Mohamed M.; Shaban, Shaban Y.

    2011-12-01

    A template condensation of α-diketones (biacetyl, benzile and 2,3-pentanedione) with 2-methyl-3-amino-(3 H)-quinazolin-4-one (AMQ) in the presence of CuX 2 (X = Cl -, Br -, NO3- or ClO4-) resulted in the formation of tetradentate Schiff base copper(II) complexes of the type [CuLX]X and [CuL]X 2. Structural characterization of the complex species was achieved by several physicochemical methods, namely elemental analysis, electronic spectra, IR, ESR, molar conductivity, thermal analysis (TAG & DTG), and magnetic moment measurements. The stereochemistry, the nature of the metal chelates, and the catalytic reactivity are markedly dependent upon the type of counter anions and the ligand substituent within the carbonyl moiety. A square planar monomeric structure is proposed for the perchlorate, nitrate, and bromide complexes, in which the counter anions are loosely bonded to copper(II) ion. For the chloride complexes, the molar conductivities and the spectral data indicated that they have square-pyramidal environments around copper(II) center. The reported copper(II) complexes exhibit promising tyrosinase catalytic activity towards the hydroxylation of phenol followed by the aerobic oxidation of the resulting catechol. A linear correlation almost exists between the catalytic reactivity and the Lewis-acidity of the central copper(II) ion created by the donating properties of the parent ligand. The steric considerations could be accounted to clarify the difference in the catalytic activity of these functional models.

  18. 76 FR 37690 - CooperVision, Inc.; Filing of Color Additive Petitions

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-06-28

    ... anthraquinone (C.I. Reactive Blue 246; CAS Reg. No. 121888-69-5) (CAP 1C0291) and 1,4- bis -9,10-anthracenedione... additive regulations be amended to provide for the safe use of 1,4- bis anthraquinone (C.I. Reactive Blue 246) and 1,4-bis -9,10-anthracenedione bis(2-methyl-2-propenoic)ester (C.I. Reactive Blue 247)....

  19. Crystal structure of 1-(5-amino-2H-tetra­zol-2-yl)-2-methyl­propan-2-ol

    PubMed Central

    Park, Hyun Sik; Ryu, Ji Yeon; Lee, Junseong

    2015-01-01

    The title compound, C5H11N5O, crystallized with two independent mol­ecules in the asymmetric unit. The two mol­ecules differ in the orientation of the 2-methyl­propan-2-ol unit, with the hy­droxy H atoms pointing in opposite directions. In the crystal, mol­ecules are linked via O—H⋯O and N—H⋯O hydrogen bonds, forming ribbons propagating along [10-1]. The ribbons are linked via N—H⋯N hydrogen bonds, forming a three-dimensional structure. PMID:26870496

  20. Volumetric Properties of the Mixture Propenenitrile C3H3N + C3H6O2 Methyl ethanoate (VMSD1511, LB4267_V)

    NASA Astrophysics Data System (ADS)

    Cibulka, I.; Fontaine, J.-C.; Sosnkowska-Kehiaian, K.; Kehiaian, H. V.

    This document is part of Subvolume C 'Binary Liquid Systems of Nonelectrolytes III' of Volume 26 'Heats of Mixing, Vapor-Liquid Equilibrium, and Volumetric Properties of Mixtures and Solutions' of Landolt-Börnstein Group IV 'Physical Chemistry'. It contains the Chapter 'Volumetric Properties of the Mixture Propenenitrile C3H3N + C3H6O2 Methyl ethanoate (VMSD1511, LB4267_V)' providing data from direct measurement of low-pressure thermodynamic speed of sound at variable mole fraction and constant temperature, in the single-phase region(s).

  1. Volumetric Properties of the Mixture Propenenitrile C3H3N + C3H6O2 Methyl ethanoate (VMSD1111, LB4251_V)

    NASA Astrophysics Data System (ADS)

    Cibulka, I.; Fontaine, J.-C.; Sosnkowska-Kehiaian, K.; Kehiaian, H. V.

    This document is part of Subvolume C 'Binary Liquid Systems of Nonelectrolytes III' of Volume 26 'Heats of Mixing, Vapor-Liquid Equilibrium, and Volumetric Properties of Mixtures and Solutions' of Landolt-Börnstein Group IV 'Physical Chemistry'. It contains the Chapter 'Volumetric Properties of the Mixture Propenenitrile C3H3N + C3H6O2 Methyl ethanoate (VMSD1111, LB4251_V)' providing data from direct low-pressure measurement of mass density at variable mole fraction and constant temperature, in the single-phase region(s).

  2. Volumetric Properties of the Mixture Propenenitrile C3H3N + C3H6O2 Methyl ethanoate (VMSD1212, LB4261_V)

    NASA Astrophysics Data System (ADS)

    Cibulka, I.; Fontaine, J.-C.; Sosnkowska-Kehiaian, K.; Kehiaian, H. V.

    This document is part of Subvolume C 'Binary Liquid Systems of Nonelectrolytes III' of Volume 26 'Heats of Mixing, Vapor-Liquid Equilibrium, and Volumetric Properties of Mixtures and Solutions' of Landolt-Börnstein Group IV 'Physical Chemistry'. It contains the Chapter 'Volumetric Properties of the Mixture Propenenitrile C3H3N + C3H6O2 Methyl ethanoate (VMSD1212, LB4261_V)' providing data by calculation of molar excess volume from low-pressure density measurements at variable mole fraction and constant temperature.

  3. Volumetric Properties of the Mixture Propenenitrile C3H3N + C3H6O2 Methyl ethanoate (VMSD1412, LB4273_V)

    NASA Astrophysics Data System (ADS)

    Cibulka, I.; Fontaine, J.-C.; Sosnkowska-Kehiaian, K.; Kehiaian, H. V.

    This document is part of Subvolume C 'Binary Liquid Systems of Nonelectrolytes III' of Volume 26 'Heats of Mixing, Vapor-Liquid Equilibrium, and Volumetric Properties of Mixtures and Solutions' of Landolt-Börnstein Group IV 'Physical Chemistry'. It contains the Chapter 'Volumetric Properties of the Mixture Propenenitrile C3H3N + C3H6O2 Methyl ethanoate (VMSD1412, LB4273_V)' providing data by calculation of isentropic compressibility from low-pressure density and thermodynamic speed of sound data at variable mole fraction and constant temperature, in the single-phase region(s).

  4. 2-Methyl­pyridinium 5-(2,4-dinitro­phen­yl)-1,3-dimethyl­barbiturate

    PubMed Central

    Sridevi, Gunaseelan; Kalaivani, Doraisamyraja

    2012-01-01

    In the title mol­ecular salt [systematic name: 2-methyl­pyridinium 5-(2,4-dinitro­phen­yl)-1,3-dimethyl-2,6-dioxo-1,2,3,6-tetra­hydro­pyrimidin-4-olate], C6H8N+·C12H9N4O7 −, the cation and anion are linked a through strong N—H⋯O hydrogen bond. In the crystal, C—H⋯O inter­actions link the ions, generating a chain along [010]. PMID:22589914

  5. Structure and spectroscopic properties of N,S-coordinating 2-methyl­sulfanyl-N-[(1H-pyrrol-2-yl)methyl­idene]aniline methanol monosolvate

    PubMed Central

    Richards, D. Douglas; Ang, M. Trisha C.; McDonald, Robert; Bierenstiel, Matthias

    2015-01-01

    The reaction of pyrrole-2-carboxaldehyde and 2-(methyl­sulfan­yl)aniline in refluxing methanol gave an olive-green residue in which yellow crystals of the title compound, C12H12N2S·CH3OH, were grown from slow evaporation of methanol at 263 K. In the crystal, hydrogen-bonding inter­actions link the aniline mol­ecule and a nearby methanol solvent mol­ecule. These units are linked by a pair of weak C—H⋯Omethanol interactions, forming inversion dimers consisting of two main molecules and two solvent molecules. PMID:26594390

  6. Mechanism and regioselectivity of the reversible Diels-Alder cycloaddition of 2-methyl-1,3 butadiene with C48B6N6 heterofullerene: a DFT approach.

    PubMed

    Zahedi, Ehsan

    2014-09-01

    A theoretical study of the mechanism and regioslectivity of Diels-Alder [4+2] cycloaddition reactions between 2-methyl-1,3 butadiene and hetero bonds of the most stable isomer of C48B6N6 heterofullerene have been studied at the B3LYP/6-31G(*) level. Three heterobond pathways BC, BN and NC including two regioisomers for each one are considered by different approaches. All studied reactions have normal electron demand nature and corresponding regioisomers are produced via asynchronous processes. Predicted regioselectivities using electronic and energetic results are in complete agreement with each other and show that BC heterobond pathway is more active than others and regioisomer 16 is the major. The local reactivity difference values (Rk) show that all reaction sites at C48B6N6 present ambiphilic activation while reaction sites at 2-methyl-1,3 butadiene show nucleophilic activation. Therefore, it is predictable that C48B6N6 should present electrophilic nature. Plotting of ΔRk and Δs values of six studied channels toward corresponding activation Gibbs free energies showed that the regioisomeric channel with lower ΔRk and Δs values is faster and vice versa. PMID:25203975

  7. Fixation of chiral smectic liquid crystal (S)-(+)-4-(2-methyl-1-butyloyloxy)phenyl 4-[1-(propenoyloxy) butiloxy] benzoate using UV curing techniques

    NASA Astrophysics Data System (ADS)

    Afrizal, Hikam, Muhammad; Soegiyono, Bambang; Riswoko, Asep; Nurdelima, Umeir

    2014-03-01

    Chiral Smectic Liquid Crystal (S)-(+)-4-(2-methyl-1-butyloyloxy)phenyl 4-[1-(propenoyloxy) butiloxy] benzoate has been synthesized using method of steglich esterification at room temperature. The mesomorphic behavior of chiral smectic at 55°C that showed schlieren texture in POM analysis. Fixation of structure chiral smectic liquid crystal by means of photopolymerization of monomer (S)-(+)-4-(2-methyl-1-butyloyloxy)phenyl 4-[1-(propenoyloxy) butiloxy] benzoate under UV irradiation which called UV curing techniques. The curing process using UV 3 lamps 100 volt at 60°C for an hour. The product of photopolymerization could be seen by analysis of FTIR spectra both monomer and polymer. FTIR spectra of monomer, two peaks for ester carbonyl and C-C double bond groups appeared at 1729.09 cm-1and 3123.46 cm-1. After UV curing process, peak for the carbonyl group at 1729.09 cm-1 decreased and a new peak at 1160.21 cm-1 appeared due to the carbonyl group attached to a C-C bond group and then peak at 3123.46 cm-1 for C-C double bond group was disappeared.

  8. Conformational polymorphs of isobutyl-6-amino-5-cyano-2-methyl-4-phenyl-4H-pyran-3-carboxylate: spectroscopic, structural and DFT approach.

    PubMed

    Prasad, A Aditya; Kumar, C Udhaya; Prakasam, B Arul; Meenakshisundaram, S P

    2016-06-01

    The crystal structure of a new crystalline phase, polymorph (II) of isobutyl-6-amino-5-cyano-2-methyl-4-phenyl-4H-pyran-3-carboxylate, was accurately determined by single-crystal X-ray diffraction analysis providing a clean identification of polymorphic forms. Comparison with a known phase, referred to as polymorph (I), reveals the type of supramolecular assembly. Inter- and intramolecular hydrogen-bonding interactions exhibit various supramolecular architectures in crystal packing and these variations confirm well the polymorphism in isobutyl-6-amino-5-cyano-2-methyl-4-phenyl-4H-pyran-3-carboxylate (IAPC) crystal structure. Crystal cohesion is achieved by N-H...N, N-H...O and C-H...H-C interactions, responsible for the formation and strengthening of the supramolecular assembly. The objective of this investigation is to study crystalline forms which can offer enhanced physicochemical properties, and also to recognize the molecular orientations between such forms. The conformational polymorphs of IAPC were compared spectroscopically by FT-IR and FT-Raman. The bulk phases were studied by X-ray powder diffraction patterns. External morphology was investigated using scanning electron microscopic images. The molecular interactions were quantified using Hirshfeld surface and fingerprint analysis. Density functional theory (DFT) computations were used to optimize the structure. The optimized structure is further subjected to an analysis of Mulliken population, natural population and electrostatic potential. PMID:27240761

  9. The value of SHOX2 methylation test in peripheral blood samples used for the differential diagnosis of lung cancer and other lung disorders.

    PubMed

    Konecny, M; Markus, J; Waczulikova, I; Dolesova, L; Kozlova, R; Repiska, V; Novosadova, H; Majer, I

    2016-01-01

    Methylation of the cytosine residues within the CpG dinucleotides plays an important role in the fundamental cellular processes, human diseases and even cancer. The DNA methylation represents a very stable sign and therefore may be used as a valuable marker for cancer screening. Epigenetic cancer biomarkers are independent of classical morphology and thus show extensive potential to overcome the limitations of cytology. Several epigenetic cancer markers have been reported to be detectable in body fluids such as bronchial aspirate, sputum, plasma and serum.Short stature homeobox gene 2 (SHOX2) encodes a homeo-domain transcription factor, which has been identified as a close homologue of the SHOX gene and both genes are involved in skeletogenesis and heart development. Methylation of SHOX2 gene has been shown to be present at high prevalence in carcinomas of lung, however may also be used to identify other tumour entities.In the presented study, we have compared suitability of two types of material associated with lung cancer for the detection of SHOX2 methylation. We have confirmed that methylation of SHOX2 gene represents reliable marker of lung malignancies. The parallel tests in the blood plasma revealed that it may represent a good alternative material for testing of the SHOX2 methylation, making the test available to patients who are unable to undergo bronchoscopy. PMID:26774146

  10. Effects of 5-chloro-2-methyl-4-isothiazolin-3-one and other candidate biodiesel biocides on rat alveolar macrophages and NR8383 cells.

    PubMed

    Poon, R; Rigden, M; Edmonds, N; Charman, N; Lamy, S

    2011-11-01

    Biocides are added to biodiesels to inhibit and remove microbial growth. The effects of 5-chloro-2-methyl-4-isothiazolin-3-one (CMIT), a candidate biodiesel biocide, were studied using freshly isolated rat alveolar macrophages (AM) and NR8383 cell line. CMIT markedly inhibited phagocytic oxidative burst as measured by zymosan-induced chemiluminescence, and cellular cytokine secretion as measured by zymosan-induced TNF-α secretion. The 50% inhibition concentration (LC(50)) for CMIT was 0.002-0.004 mM for both cellular functions. AM exposed to CMIT for as little as 2 min showed markedly inhibited functions that persisted for at least 5 h. Sodium metabisulfite was able to partially neutralize the inhibitory activity of CMIT. Cysteine and glutathione, when present at a molar ratio of 2-1 or higher against CMIT, were effective neutralizers, while serine, histidine, alanine, and albumin were without effect. When the AM testing system was used to compare the toxicity of CMIT against three other candidate biodiesel biocides, methylene dithiocyanate (MDC) was found to be of comparable toxicity to CMIT, 2-methyl-4-isothiazolin-3-one (MIT) was much less toxic, and dimethyl acetylenedicarboxylate (DMAD) was non-toxic. Because AM is among the first cell-type exposed to inhaled biodiesel aerosols, the result suggested that CMIT present in biodiesel may produce respiratory effects, and further investigations including animal studies are warranted. PMID:21445588

  11. Fixation of chiral smectic liquid crystal (S)-(+)-4-(2-methyl-1-butyloyloxy)phenyl 4-[1-(propenoyloxy) butiloxy] benzoate using UV curing techniques

    SciTech Connect

    Afrizal, Nurdelima,; Umeir; Hikam, Muhammad; Soegiyono, Bambang; Riswoko, Asep

    2014-03-24

    Chiral Smectic Liquid Crystal (S)-(+)-4-(2-methyl-1-butyloyloxy)phenyl 4-[1-(propenoyloxy) butiloxy] benzoate has been synthesized using method of steglich esterification at room temperature. The mesomorphic behavior of chiral smectic at 55°C that showed schlieren texture in POM analysis. Fixation of structure chiral smectic liquid crystal by means of photopolymerization of monomer (S)-(+)-4-(2-methyl-1-butyloyloxy)phenyl 4-[1-(propenoyloxy) butiloxy] benzoate under UV irradiation which called UV curing techniques. The curing process using UV 3 lamps 100 volt at 60°C for an hour. The product of photopolymerization could be seen by analysis of FTIR spectra both monomer and polymer. FTIR spectra of monomer, two peaks for ester carbonyl and C-C double bond groups appeared at 1729.09 cm-1and 3123.46 cm{sup −1}. After UV curing process, peak for the carbonyl group at 1729.09 cm{sup −1} decreased and a new peak at 1160.21 cm{sup −1} appeared due to the carbonyl group attached to a C-C bond group and then peak at 3123.46 cm{sup −1} for C-C double bond group was disappeared.

  12. DFT STUDY OF THE ISOMERIZATION OF HEXYL SPECIES INVOLVED IN THE ACID-CATALYZED CONVERSION OF 2-METHYL-PENTENE-2. (R825370C056)

    EPA Science Inventory

    The perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Concl...

  13. Crystal structure of 2-{[1-(2-methyl-5-nitro-1H-imidazol-1-yl)propan-2-yl­oxy]carbon­yl}benzoic acid

    PubMed Central

    Shahid, Hafiz Abdullah; Jahangir, Sajid; Shah, Syed Adnan Ali; Zaki, Hamizah Mohd; Naz, Humera

    2014-01-01

    In the title compound, C15H15N3O6, the dihedral angle between the planes of the benzene and imidazole rings is 34.93 (10)°. An intra­molecular C—H⋯O hydrogen bond is observed. In the crystal, O—H⋯N hydrogen bonds link the mol­ecules into chains parallel to the c axis. PMID:25553019

  14. Crystal structure of bis­(2-methyl-1H-imidazol-3-ium) μ-oxalato-bis­[n-butyl­tri­chlorido­stannate(IV)

    PubMed Central

    Diop, Mouhamadou Birame; Diop, Libasse; Oliver, Allen G.

    2016-01-01

    The SnIV atom in the centrosymmetric anion of the title salt, (C4H7N2)2[Sn2(C4H9)2(C2O4)Cl6], is coordinated in a distorted octa­hedral mode by two O atoms of a bridging oxalate moiety, three Cl atoms and a C atom of an n-butyl group. The latter is disordered over two sets of sites in a 0.66:0.33 occupancy ratio. N—H⋯O and N—H⋯Cl hydrogen bonds involving the 2-methyl­imidazolium cation and neighbouring anions result in the formation of chains extending parallel to [001]. PMID:27308059

  15. The conformational energies of 2-methyl- and 4-methyl-1,3-dithiane. The breakdown of 1,3- syn diaxial repulsion hypothesis

    NASA Astrophysics Data System (ADS)

    Ribeiro, Douglas S.; Rittner, Roberto

    2003-09-01

    The conformational enthalpies (Δ H) of 2-methyl- (-1.76 kcal mol -1) and 4-methyl-1,3-dithiane (-1.75 kcal mol -1) were obtained by the analysis of 13C chemical shifts as a function of temperature. These energies are in excellent agreement both with calculated values (B3LYP/6-31G(d,p)) and with literature values based on 2,4-dialkyl-1,3-dithiane. The results confirm the similarity between the conformational energies of the methyl group at the 2 and 4 positions of the dithiane ring and that of methylcyclohexane, despite the larger distances between ring 1,3- syn- axial hydrogens and the closest methyl axial hydrogen in the dithiane ring. The possibility of a buttressing effect on the 2,4-dialkyl-1,3-dithianes previously studied and the rationale of 1,3- syn-axial steric interaction are discussed.

  16. Properties of 4-dicyanomethylene-2-methyl-6-(p-dimethyl-aminostyryl)-4H-pyran-doped Alq layers as optically pumped lasers

    NASA Astrophysics Data System (ADS)

    Jakabovič, J.; Lengyel, O.; Kováč, J.; Wong, T. C.; Lee, C. S.; Lee, S. T.

    2003-08-01

    The optical properties of tris-(8-hydroxyquinoline) aluminum (Alq) doped with 4-dicyanomethylene-2-methyl-6-(p-dimethyl-aminostyryl)-4H-pyran (DCM) in solutions and in solid films were studied by measuring the steady-state excitation and spontaneous emission spectra. The emission peak in the solid films shifted from 628 to 659 nm as the doping concentration of DCM changed from 0.9% to 11%. The optically pumped waveguide lasers were fabricated by coevaporation of Alq films with 1.3 wt % DCM onto gallium arsenide (GaAs) substrates using silicon dioxide (SiO2) and magnesium fluoride (MgF2) as cladding layers. Both types of waveguide laser structures showed optical confinement and simulated emission at a threshold pumping energy near 1.4 μJ. The result suggests a thin MgF2 may be used as a confinement layer that has the advantage of preparation by low-temperature evaporation.

  17. Crystal structure of bis-(2-methyl-1H-imidazol-3-ium) μ-oxalato-bis-[n-butyl-tri-chlorido-stannate(IV)].

    PubMed

    Diop, Mouhamadou Birame; Diop, Libasse; Oliver, Allen G

    2016-06-01

    The Sn(IV) atom in the centrosymmetric anion of the title salt, (C4H7N2)2[Sn2(C4H9)2(C2O4)Cl6], is coordinated in a distorted octa-hedral mode by two O atoms of a bridging oxalate moiety, three Cl atoms and a C atom of an n-butyl group. The latter is disordered over two sets of sites in a 0.66:0.33 occupancy ratio. N-H⋯O and N-H⋯Cl hydrogen bonds involving the 2-methyl-imidazolium cation and neighbouring anions result in the formation of chains extending parallel to [001]. PMID:27308059

  18. Conformations of solid 2-methyl-4-( p-X-phenylazo)imidazoles by 13C CP MAS NMR spectroscopy and PM3 semi-empirical calculations

    NASA Astrophysics Data System (ADS)

    Maciejewska, Dorota

    1999-03-01

    Solid 2-methyl-4-( p-X-phenylazo)imidazoles form hydrogen bonded chains with N-H⋯N bonds and C-H⋯O or C-H⋯N interaction. Depending on the nature and orientation of the substituents X it was possible to identify one tautomer if XH ( 2), Br ( 3), NO 2 ( 4) and the two, a- and b-tautomers in the crystal unit if XOCH 3 ( 1). The 13C CP MAS NMR spectra of ( 4) indicate the presence of phenyl ring dynamics. A preferred structure present in the solid state is that with different lengths of C1'-N and C4-N bonds and with higher dipole moment.

  19. Crystallization of lysozyme with (R)-, (S)- and (RS)-2-methyl-2,4-pentanediol

    SciTech Connect

    Stauber, Mark; Jakoncic, Jean; Berger, Jacob; Karp, Jerome M.; Axelbaum, Ariel; Sastow, Dahniel; Buldyrev, Sergey V.; Hrnjez, Bruce J.; Asherie, Neer

    2015-03-01

    Chiral control of crystallization has ample precedent in the small-molecule world, but relatively little is known about the role of chirality in protein crystallization. In this study, lysozyme was crystallized in the presence of the chiral additive 2-methyl-2,4-pentanediol (MPD) separately using the R and S enantiomers as well as with a racemic RS mixture. Crystals grown with (R)-MPD had the most order and produced the highest resolution protein structures. This result is consistent with the observation that in the crystals grown with (R)-MPD and (RS)-MPD the crystal contacts are made by (R)-MPD, demonstrating that there is preferential interaction between lysozyme and this enantiomer. These findings suggest that chiral interactions are important in protein crystallization.

  20. Scalable synthesis of the unusual amino acid segment (ADMOA unit) of marine anti-inflammatory peptide: solomonamide A.

    PubMed

    Kavitha, Nerella; Chandrasekhar, Srivari

    2015-06-14

    The most abundantly available hexose sugar, d-glucose has been converted to protected 4-amino(2'amino-4'-hydroxy phenyl)-3,5-dihydroxy-2-methyl-6-oxo hexanoic acid (protected ADMOA, 3), the unusual amino acid present in marine natural product solomonamide A in gram quantities involving easy to operate chemical transformations. PMID:25960353

  1. Electron collisions with methyl-substituted ethylenes: Cross section measurements and calculations for 2-methyl-2-butene and 2,3-dimethyl-2-butene

    NASA Astrophysics Data System (ADS)

    Szmytkowski, Czesław; Stefanowska, Sylwia; Zawadzki, Mateusz; Ptasińska-Denga, ElŻbieta; MoŻejko, Paweł

    2015-08-01

    We report electron-scattering cross sections determined for 2-methyl-2-butene [(H3C)HC = C(CH3)2] and 2,3-dimethyl-2-butene [(H3C)2C = C(CH3)2] molecules. Absolute grand-total cross sections (TCSs) were measured for incident electron energies in the 0.5-300 eV range, using a linear electron-transmission technique. The experimental TCS energy dependences for the both targets appear to be very similar with respect to the shape. In each TCS curve, three features are discernible: the resonant-like structure located around 2.6-2.7 eV, the broad distinct enhancement peaking near 8.5 eV, and a weak hump in the vicinity of 24 eV. Theoretical integral elastic (ECS) and ionization (ICS) cross sections were computed up to 3 keV by means of the additivity rule (AR) approximation and the binary-encounter-Bethe method, respectively. Their sums, (ECS+ICS), are in a reasonable agreement with the respective measured TCSs. To examine the effect of methylation of hydrogen sides in the ethylene [H2C = CH2] molecule on the TCS, we compared the TCS energy curves for the sequence of methylated ethylenes: propene [H2C = CH(CH3)], 2-methylpropene [H2C = C(CH3)2], 2-methyl-2-butene [(H3C)HC = C(CH3)2], and 2,3-dimethyl-2-butene [(H3C)2C = C(CH3)2], measured in the same laboratory. Moreover, the isomeric effect is also discussed for the C5H10 and C6H12 compounds.

  2. A novel 3-acetoxy-2-methyl-N-(4-methoxyphenyl)benzamide: Molecular structural describe, antioxidant activity with use X-ray diffractions and DFT calculations

    NASA Astrophysics Data System (ADS)

    Demir, Sibel; Cakmak, Sukriye; Dege, Necmi; Kutuk, Halil; Odabasoglu, Mustafa; Kepekci, R. Aysun

    2015-11-01

    In this work, the structure of a novel 3-acetoxy-2-methyl-N-(4-methoxyphenyl) benzamide, was analyzed both experimentally and theoretically using three methods, X-ray single crystal diffraction technique, IR spectroscopy, and quantum chemical computation. The X-ray diffraction analysis indicates that 3-acetoxy-2-methyl-N-(4-methoxyphenyl) benzamide molecula crystallizes in a triclinic system (space group P-1) and the calculated lattice constants are, a = 5.1205 ± 0.0004 Å, b = 9.8598 ± 0.0008 Å, c = 15.3398 ± 0.0013 Å, α = 80.79(7)°, β = 83.142(6)°, γ= 85.411(6)°, and Z = 2. In addition, the molecular geometry and vibrational frequencies of the title compound in ground state have been calculated using density functional theory (DFT) at B3LYP level 6-31G+(d,p) basis set. The geometrical parameters of the title compound obtained from XRD studies are good in agreement with the calculated values. The electronic properties, such as HOMO and LUMO energies and thermodynamic properties were calculated with DFT (using B3LYP/6-31G+(d,p) basis set) approach. To estimate the chemical reactivity of the molecule, the molecular electrostatic potential (MEP) surface map of the title molecule and PES scan were investigated with theoretical calculations at the B3LYP/6-31+G(d,p) and B3LYP/3-21G levels, respectively. Antioxidant properties are determined using DPPH free radical scavenging test.

  3. Temperature-dependence of the influence of the position-2-methyl group on the structure-directing effect of piperazine in the synthesis of open-framework aluminophosphates

    PubMed Central

    Huang, Pai; Xu, Jun; Qi, Guodong; Deng, Feng; Xu, Ruren; Yan, Wenfu

    2016-01-01

    The temperature-dependence of the influence of the position-2-methyl group on the structure-directing effect of piperazine in the synthesis of open-framework aluminophosphates was investigated. By heating the initial mixture with the composition of Al2O3:1.5 P2O5:R:125 H2O at 160 °C, where R is the structure-directing agent of 2-methylpiperazine or piperazine, layered aluminophosphates APMeP150 (R = 2-methylpiperazine) and AP2pip (R = piperazine) were obtained. When the same initial reaction mixture was heated at 190 °C, layered aluminophosphates APMeP200 (R = 2-methylpiperazine) and AP2pip (R = piperazine) were crystallized. APMeP200 and AP2pip have the same inorganic sheet topology. We investigated the crystallization processes of the four open-framework aluminophosphates and found that increasing the heating temperature slowed the crystallization of the initial mixtures. The non-bonding interactions between the inorganic layers of the four open-framework aluminophosphates and the experimental or theoretically generated structure-directing agents were calculated. The possible starting points of the crystallization of the four open-framework aluminophosphates were analysed and compared. The temperature-dependence of the influence of the position-2-methyl group on the structure-directing effect of piperazine revealed that the structure-directing effect, the most important factor in the synthesis of zeolites and related open-framework materials, is determined by multiple factors. The structural parameters of the same compound can be affected by the synthesis conditions. PMID:26912387

  4. Anchoring the gas-phase acidity scale: From formic acid to methanethiol

    NASA Astrophysics Data System (ADS)

    Eyet, Nicole; Villano, Stephanie M.; Bierbaum, Veronica M.

    2009-06-01

    We have measured the gas-phase acidities of nine compounds: formic acid, acetic acid, 1,3-propanedithiol, 2-methyl-2-propanethiol, 3-methyl-1-butanethiol, 2-propanethiol, 1-propanethiol, ethanethiol, and methanethiol, with acidities ranging from 338.6 to 351.1 kcal mol-1 using proton transfer kinetics and the resulting equilibrium constants. These acids were anchored to the well-known acidity of hydrogen sulfide; the measured acidities are in good agreement with previous experimental values, but error bars are significantly reduced. The gas-phase acidity of 3-methyl-1-butanethiol was determined to be 347.1 (5) kcal mol-1; there were no previous measurements of this value. Entropies of deprotonation were calculated and enthalpies of deprotonation were determined.

  5. 21 CFR 177.1211 - Cross-linked polyacrylate copolymers.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...). The solvent used shall be at least 60 milliliters aqueous sodium chloride solution per gram of... grafted copolymer of cross-linked sodium polyacrylate identified as 2-propenoic acid, polymers with N,N-di-2-propenyl-2-propen-1-amine and hydrolyzed polyvinyl acetate, sodium salts, graft (CAS Reg....

  6. Polydopamine-assisted partial hydrolyzed poly(2-methyl-2-oxazolinze) as coating for determination of melamine in milk by capillary electrophoresis.

    PubMed

    Zhang, Yalin; Chen, Lijuan; Zhang, Chong; Liu, Songtao; Zhu, Haikun; Wang, Yanmei

    2016-04-01

    Nitrogen-rich melamine (66% by mass) had been found to be illegally adulterated to milk products and animal feed in order to increase the apparent protein content, and ingestion of melamine may lead to the formation of kidney stones. Hence, the development of reliable analytical methods for the monitoring of melamine in milk products is necessary. The common methods for melamine analysis in milk products are performed via GC-MS or HPLC, however, these procedures require a large of organic solvent and several pretreatment steps. In this study, a new and facile approach was developed to modify a fused-silica capillary inner surface based on poly(dopamine) (PDA) and partial hydrolyzed poly(2-methyl-2-oxazoline) (PMOXA-EI) mixed coating, which was used to determine the melamine in milk powder quantitatively by capillary electrophoresis with ultraviolet (CE-UV) detection with simple analytes pretreatment. Firstly, the influences of the molecular mass of poly(2-methyl-2-oxazoline) (PMOXA), the hydrolysis degree of PMOXA, and the concentration ratio of DA to PMOXA-EI on the separation properties of a mixture of four basic proteins (cytochrome c, lysozyme, ribonuclease A, and α-chymotrypsinogen A) were studied in detail. As a consequence, fast and efficient separation of four proteins was obtained using PDA/PMOXA1k-EI0.4 coating (once coating). Then, a modified facile coating workflow was carried out to acquire a novel twice coating (i.e. PDA/PMOXA1k-EI0.4+PMOXA1k-EI0.4 coated capillary) for highly sensitive and stable analysis of melamine. Under the optimal conditions, the linear response of melamine concentration ranged from 6.25 to 100 µg/mL with high correlation coefficient of 0.9910, and the limit of detection (LOD) for melamine was 0.097 µg/mL. The minimum amount of melamine determined in milk powder with our proposed method was 4 mg/kg. The recoveries and relative standard deviations (RSDs) were 92.13-102.47%, 92.22-100.30%, 2.07-4.98%, and 2

  7. 40 CFR 721.2078 - 1-Piperidinecarboxylic acid, 2-[(dichloro-hydroxy-carbomonocycle)hydrazono]-, methyl ester...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... generically identified as 1-piperidinecarboxylic acid, 2- -, methyl ester (PMN P-96-756) is subject to....125 (a), (b), (c), (d), (f), (g), (h), and (i) are applicable to manufacturers, importers, and... AGENCY (CONTINUED) TOXIC SUBSTANCES CONTROL ACT SIGNIFICANT NEW USES OF CHEMICAL SUBSTANCES...

  8. 40 CFR 721.2078 - 1-Piperidinecarboxylic acid, 2-[(dichloro-hydroxy-carbomonocycle)hydrazono]-, methyl ester...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... generically identified as 1-piperidinecarboxylic acid, 2- -, methyl ester (PMN P-96-756) is subject to....125 (a), (b), (c), (d), (f), (g), (h), and (i) are applicable to manufacturers, importers, and... AGENCY (CONTINUED) TOXIC SUBSTANCES CONTROL ACT SIGNIFICANT NEW USES OF CHEMICAL SUBSTANCES...

  9. Efficient transfer of information from hexitol nucleic acids to RNA during nonenzymatic oligomerization

    NASA Technical Reports Server (NTRS)

    Kozlov, I. A.; De Bouvere, B.; Van Aerschot, A.; Herdewijn, P.; Orgel, L. E.

    1999-01-01

    Hexitol nucleic acids (HNAs) are DNA analogues that contain the standard nucleoside bases attached to a phosphorylated 1,5-anhydrohexitol backbone. We find that HNAs support efficient information transfer in nonensymatic template-directed reactions. HNA heterosequences appeared to be superior to the corresponding DNA heterosequences in facilitating synthesis of complementary oligonucleotides from nucleoside-5'-phosphoro-2-methyl imidazolides.

  10. Stability constants and molar absorptivities for complexes of copper(II) with N-methyldiethanolamine, 1,4-bis(2-hydroxypropyl)-2-methylpiperazine, and 2-amino-2-methyl-1-propanol.

    PubMed

    Siefker, J R; Aroc, R V

    1986-09-01

    The stability constants and molar absorptivities of complexes of Cu(2+) with N-methyldiethanolamine, 1,4-bis(2-hydroxypropyl)-2-methylpiperazine, and 2-amino-2-methyl-1-propanol have been determined from spectrophotometric data for very dilute aqueous solutions. PMID:18964197

  11. Inhibitory effect of 2-methyl-naphtho[1,2,3-de]quinolin-8-one on melanosome transport and skin pigmentation

    PubMed Central

    Park, Jong il; Lee, Ha Yeon; Lee, Ji Eun; Myung, Cheol hwan; Hwang, Jae Sung

    2016-01-01

    Melanosomes are lysosome-related organelles with specialized capabilities of melanin synthesis and movement mediated by the Rab27a-Melanophilin-MyosinVa protein complex. In this study, we found that 2-methyl-naphtho[1,2,3-de]quinolin-8-one (MNQO) induced melanosome aggregation around the nucleus in melan-a melanocytes and in melan-a melanocytes/SP-1 keratinocyte co-cultures without inducing toxicity or changing the melanin content. Western blot and real-time PCR analyses showed that MNQO decreased expression of the Rab27a, Melanophilin and MyosinVa proteins and mRNAs, respectively, in melan-a melanocytes. In a reconstituted human epidermis model, treatment with 0.001% MNQO reduced skin pigmentation. Also, MNQO reduced skin pigmentation in brown guinea pigs induced by UVB irradiation. These results indicated that regulation of melanosome transport may serve as a good target for new skin depigmenting agents and MNQO itself could be a candidate. PMID:27381646

  12. A study of the molecular structure and vibrational spectra of 1,3-dichloro-2-propanol and 1,1,1-trichloro-2-methyl-2-propanol (chlorobutanol).

    PubMed

    Badawi, Hassan M

    2012-02-15

    The conformational stability of 1,3-dichloro-2-propanol and 1,1,1-trichloro-2-methyl-2-propanol (chlorobutanol) was investigated by the DFT-B3LYP/6-311+G**, MP2/6-311+G** and MP4(SDQ)/6-311+G** levels of theory. From the calculations chlorobutanol was predicted to exist in a non-planar gauche structure. The planar cis and trans structures of chlorobutanol were calculated to be about 3kcal/mol higher in energy than the gauche structure. From the calculations 1,3-dichloro-2-propanol was predicted to exist in a Ggg1 and Ggg conformational mixture at ambient temperature. In the low energy structures of both alcohols the non-bonded Cl⋯H(O) distance was calculated to be of about 2.6-2.7Å. The observation of a broad and very intense band at about 3400cm(-1) in the infrared spectra of the two alcohols supports the presence of strong intermolecular Cl⋯H(O) dipolar interactions in their condensed phases. The analysis of the Raman spectra of 1,3-dichloro-2-propanol suggests the presence of a second high energy Ggg structure of the dichloride at room temperature. The vibrational frequencies of 1,3-dichloro-2-propanol and chlorobutanol in their low energy structures were computed at the B3LYP level and tentative vibrational assignments were made for their normal modes on the basis of combined calculated and experimental data. PMID:22154261

  13. A study of the molecular structure and vibrational spectra of 1,3-dichloro-2-propanol and 1,1,1-trichloro-2-methyl-2-propanol (chlorobutanol)

    NASA Astrophysics Data System (ADS)

    Badawi, Hassan M.

    2012-02-01

    The conformational stability of 1,3-dichloro-2-propanol and 1,1,1-trichloro-2-methyl-2-propanol (chlorobutanol) was investigated by the DFT-B3LYP/6-311+G**, MP2/6-311+G** and MP4(SDQ)/6-311+G** levels of theory. From the calculations chlorobutanol was predicted to exist in a non-planar gauche structure. The planar cis and trans structures of chlorobutanol were calculated to be about 3 kcal/mol higher in energy than the gauche structure. From the calculations 1,3-dichloro-2-propanol was predicted to exist in a Ggg1 and Ggg conformational mixture at ambient temperature. In the low energy structures of both alcohols the non-bonded Cl⋯H(O) distance was calculated to be of about 2.6-2.7 Å. The observation of a broad and very intense band at about 3400 cm -1 in the infrared spectra of the two alcohols supports the presence of strong intermolecular Cl⋯H(O) dipolar interactions in their condensed phases. The analysis of the Raman spectra of 1,3-dichloro-2-propanol suggests the presence of a second high energy Ggg structure of the dichloride at room temperature. The vibrational frequencies of 1,3-dichloro-2-propanol and chlorobutanol in their low energy structures were computed at the B3LYP level and tentative vibrational assignments were made for their normal modes on the basis of combined calculated and experimental data.

  14. Purification of a vitamin K epoxide reductase that catalyzes conversion of vitamin K 2,3-epoxide to 3-hydroxy-2-methyl-3-phytyl-2,3-dihydronaphthoquinone.

    PubMed Central

    Mukharji, I; Silverman, R B

    1985-01-01

    An enzyme from bovine liver microsomes that catalyzes the reduction of vitamin K 2,3-epoxide to 2- and 3-hydroxy-2-methyl-3-phytyl-2,3-dihydronaphthoquinone was purified 1152-fold to apparent homogeneity. Microsomes were solubilized with 3-[3-cholamidopropyl)dimethylammonio]-1-propanesulfonate (CHAPS), and the enzyme was purified by chromatography on PBE-94 ion exchanger, hydroxylapatite, and DEAE-cellulose, and then gel filtration on Sephacryl S-200. The homogeneity of the final preparation was established by polyacrylamide slab gel electrophoresis in the presence of sodium dodecyl sulfate. The molecular weight of the native enzyme is 25,000 and that of denatured enzyme is 12,400, which suggests that the enzyme is a dimer with identical subunits. No chromophoric cofactors are associated with the enzyme. Dithiothreitol and CHAPS are essential for activity, but high concentrations of glycerol reduces the activity. The enzyme is not inhibited by warfarin, a potent inhibitor of the vitamin K epoxide reductase, which catalyzes the conversion of vitamin K 2,3-epoxide to vitamin K. Evidence is presented indicating that the purified enzyme is not simply a fragment of the warfarin-sensitive vitamin K epoxide reductase. Images PMID:3857611

  15. Growth of amorphous zinc tin oxide films using plasma-enhanced atomic layer deposition from bis(1-dimethylamino-2-methyl-2propoxy)tin, diethylzinc, and oxygen plasma

    NASA Astrophysics Data System (ADS)

    Han, Jeong Hwan; Lee, Byoung Kook; Jung, Eun Ae; Kim, Hyo-Suk; Kim, Seong Jun; Kim, Chang Gyoun; Chung, Taek-Mo; An, Ki-Seok

    2015-12-01

    Amorphous ZnSnOx (ZTO) films were prepared using plasma-enhanced atomic layer deposition (PEALD) in a temperature range of 100-200 °C. Metal-organic precursors of Sn(dmamp)2 (dmamp = bis(1-dimethylamino-2-methyl-2-propoxide) and diethylzinc were employed as sources of Sn and Zn, respectively, in combination with O2 plasma as a reactant. Sn levels in the ZTO films were controlled by varying the SnO2/ZnO cycle ratio from 0 to 8. According to the growth behaviour of the ZTO film by alternating SnO2 and ZnO PEALD cycles, it was observed that ZnO growth on Sn-rich ZTO film is retarded, whereas SnO2 growth is enhanced on Zn-rich ZTO film. The chemical states of the ZTO films were confirmed by X-ray photoelectron spectroscopy (XPS); the chemical compositions of the ZTO films were characterised by XPS depth profiling. Grazing-angle X-ray diffraction revealed that the PEALD ZTO films possess an amorphous structure, irrespective of Sn levels from 20 to 59 at.%. ZTO films with intermediate Sn at.% exhibited smooth surface morphology compared to binary ZnO and SnO2 films. Additionally, the step coverage of a ZTO film deposited on hole pattern with an aspect ratio of 8 and opening diameter of 110 nm was about 93%, suggesting the realisation of self-limited growth.

  16. Comparative assessment of the stability of nonfouling poly(2-methyl-2-oxazoline) and poly(ethylene glycol) surface films: an in vitro cell culture study.

    PubMed

    Chen, Yin; Pidhatika, Bidhari; von Erlach, Thomas; Konradi, Rupert; Textor, Marcus; Hall, Heike; Lühmann, Tessa

    2014-09-01

    Poly(ethylene glycol) (PEG) has been the most frequently reported and commercially used polymer for surface coatings to convey nonfouling properties. PEGylated surfaces are known to exhibit limited chemical stability, particularly due to oxidative degradation, which limits long-term applications. In view of excellent anti-adhesive properties in the brush conformation and resistance to oxidative degradation, poly(2-methyl-2-oxazoline) (PMOXA) has been proposed recently as an alternative to PEG. In this study, the authors systematically compare the (bio)chemical stability of PEG- and PMOXA-based polymer brush monolayer thin films when exposed to cultures of human umbilical vein endothelial cells (HUVECs) and human foreskin fibroblasts (HFFs). To this end, the authors used cell-adhesive protein micropatterns in a background of the nonfouling PEG and PMOXA brushes, respectively, and monitored the outgrowth of HUVECs and HFFs for up to 21 days and 1.5 months. Our results demonstrate that cellular micropatterns spaced by PMOXA brushes are significantly more stable under serum containing cell culture conditions in terms of confinement of cells to the adhesive patterns, when compared to corresponding micropatterns generated by PEG brushes. Moreover, homogeneous PEG and PMOXA-based brush monolayers on Nb2O5 surfaces were investigated after immersion in endothelial cell medium using ellipsometry and x-ray photoelectron spectroscopy. PMID:25280844

  17. Growth, optical, luminescence, thermal and mechanical behavior of an organic single crystal: 3-Acetyl-2-methyl-4-phenylquinolin-1-ium chloride.

    PubMed

    Nirosha, M; Kalainathan, S; Sarveswari, S; Vijayakumar, V

    2014-04-01

    A single crystal of 3-acetyl-2-methyl-4-phenylquinolin-1-ium chloride has grown by slow evaporation solution growth technique using ethanol as solvent. The structural, thermal, optical and mechanical property has studied for the grown crystal. Single crystal XRD revealed that the crystal belongs to monoclinic system with space group P21/c. The presences of Functional groups in the crystallized material have confirmed using the FTIR vibrational spectrum. The optical absorbance spectrum recorded from 190 to 1100nm shows the cut-off wavelength occurs at 371nm. The material shows its transparency in the entire region of the visible spectrum. The photoluminescence spectrum shows the ultraviolet and blue emission in the crystal. Thermogravimetric and differential thermal analysis reveal the thermal stability of the grown crystal. Etching study shows the grown mechanism and surface features of the crystal. Vickers microhardness studies have carried out on the (01-1) plane to understand the mechanical properties of the grown crystal. The hardness of the title compound increases on increasing the load. The Meyer's index number (n), and the stiffness constants for different loads has calculated and reported. PMID:24389003

  18. Inhibitory effect of 2-methyl-naphtho[1,2,3-de]quinolin-8-one on melanosome transport and skin pigmentation.

    PubMed

    Park, Jong Il; Lee, Ha Yeon; Lee, Ji Eun; Myung, Cheol Hwan; Hwang, Jae Sung

    2016-01-01

    Melanosomes are lysosome-related organelles with specialized capabilities of melanin synthesis and movement mediated by the Rab27a-Melanophilin-MyosinVa protein complex. In this study, we found that 2-methyl-naphtho[1,2,3-de]quinolin-8-one (MNQO) induced melanosome aggregation around the nucleus in melan-a melanocytes and in melan-a melanocytes/SP-1 keratinocyte co-cultures without inducing toxicity or changing the melanin content. Western blot and real-time PCR analyses showed that MNQO decreased expression of the Rab27a, Melanophilin and MyosinVa proteins and mRNAs, respectively, in melan-a melanocytes. In a reconstituted human epidermis model, treatment with 0.001% MNQO reduced skin pigmentation. Also, MNQO reduced skin pigmentation in brown guinea pigs induced by UVB irradiation. These results indicated that regulation of melanosome transport may serve as a good target for new skin depigmenting agents and MNQO itself could be a candidate. PMID:27381646

  19. Synthesis and characterization of polymers and interpenetrating polymer networks (IPNs) with nonlinear optical (NLO) properties and related numerical studies

    NASA Astrophysics Data System (ADS)

    Sharma, P. R. Srikanth

    Copolymers of methyl methacrylate (MMA) and 2-propenoic acid, 2-methyl-, 2-[[[[4-methyl-3-[[[2-methyl-4-nitrophenyl)amino]carbonyl]aminophenyl]carbonyl]oxy]ethyl ester (PAMEE) exhibiting nonlinear optical (NLO) properties have been synthesized. Two kinds of urethane containing interpenetrating polymer networks (IPNs), consisting of nonlinear optical (NLO) chromophore, 2-methyl-4-nitroaniline (MNA) or Disperse Red1 (DR1) have been synthesized. The IPN systems consist of either aliphatic polycarbonate urethane (PCU) or 2,6-dimethyl-1,4-phenylene oxide (PPO) as one network and crosslinked poly (MMA-co-PAMEE) or poly (MMA-co-PMNEE) as the second network. Copolymers and interpenetrating polymer networks (IPNs) were characterized by IR spectroscopy, UV-VIS spectroscopy, differential scanning calorimetry (DSC), scanning electron microscopy (SEM), and second harmonic generation (SHG) measurements. The thin films of copolymers and IPNs were optically transparent and the corona poled polymers produced relatively large and stable SHG signals at room temperature. To understand the polarization decay of our NLO polymer we studied a simple theoretical model which can account for the main features which we observe. The addition of an apparent "chemical" reaction with a reaction activation energy EAB to the neighbor-facilitated Fredrickson-Anderson model shows the existence of a beta relaxation occurring simultaneously with the main alpha process. The combination of an Ising-model with antiferromagnetic interaction and the neighbor-facilitated Fredrickson-Anderson model allows a description of the polarization decay of polarized materials, such as our polymers, below the glass transition temperature Tg. The relaxation time for the polarization scales with the relaxation time of the alpha-process of the glass transition, and shows a typical curvature in the ln tau versus T-1 plot. Real polymers, such as poly(MMA-co-PAMEE) which we study possess both of these features and its

  20. Plumbagin (5-hydroxy-2-methyl-1,4-naphthoquinone), isolated from Plumbago zeylanica, inhibits ultraviolet radiation-induced development of squamous cell carcinomas

    PubMed Central

    Sand, Jordan M.; Hafeez, Bilal Bin; Jamal, Mohammad Sarwar; Witkowsky, Olya; Siebers, Emily M.; Fischer, Joseph; Verma, Ajit K.

    2012-01-01

    Plumbagin (PL) (5-hydroxy-2-methyl-1,4-napthoquinone), a medicinal plant-derived naphthoquinone, was isolated from the roots of the Plumbago zeylanica L. (also known as Chitrak). The roots of P. zeylanica L. have been used in Indian medicine for >2500 years as an anti-atherogenic, cardiotonic, hepatoprotective and neuroprotective agent. We present here that topical application of non-toxic doses (100–500 nmol) of PL to skin elicits dose-dependent inhibition of ultraviolet radiation (UVR)-induced development of squamous cell carcinomas (SCC). In this experiment, FVB/N mice were exposed to UVR (2 kJ/m2) three times weekly from a bank of six Kodacel-filtered FS40 sunlamps (∼60% UVB and 40% UVA). Carcinoma incidence in mice treated with vehicle, 100, 200 or 500 nmol PL, at 44 weeks post-UVR, were 86, 80 (P = 0.67), 53 (P = 0.12) and 7% (P = 0.0075), respectively. Both vehicle and PL-treated mice gained weight and did not exhibit any signs of toxicity during the entire period of the experiment. Molecular mechanisms associated with inhibition of UVR-induced development of SCC involved induction of apoptosis and inhibition of cell proliferation. Specific findings are that PL treatment (i) inhibited UVR-induced DNA binding of activating protein-1, nuclear factor-kappaB, Stat3 transcription factors and Stat3-regulated molecules (cdc25A and Survivin); (ii) inhibited protein levels of pERK1/2, PI3K85, pAKTSer473, Bcl2, BclxL, proliferating cell nuclear antigen and cell cycle inhibitory proteins p27 and p21 and (iii) increased UVR-induced Fas-associated death domain expression, poly (ADP-ribose) polymerase protein cleavage and Bax/Bcl2 ratio. Taken together, our findings suggest that PL may be a novel agent for the prevention of skin cancer. PMID:22072620

  1. ABT-089 [2-methyl-3-(2-(S)-pyrrolidinylmethoxy)pyridine dihydrochloride]: II. A novel cholinergic channel modulator with effects on cognitive performance in rats and monkeys.

    PubMed

    Decker, M W; Bannon, A W; Curzon, P; Gunther, K L; Brioni, J D; Holladay, M W; Lin, N H; Li, Y; Daanen, J F; Buccafusco, J J; Prendergast, M A; Jackson, W J; Arneric, S P

    1997-10-01

    ABT-089 [2-methyl-3-(2-(S)-pyrrolidinylmethoxy)pyridine dihydrochloride], a novel ligand at neuronal nicotinic acetylcholine receptors with reduced adverse effects and improved oral bioavailability relative to (-)-nicotine, was tested in a variety of cognitive tests in rats and monkeys. Administered acutely, ABT-089 only marginally improved the spatial discrimination water maze performance of septal-lesioned rats. However, more robust improvement (45% error reduction on the last training day) was observed when ABT-089 was administered continuously via subcutaneous osmotic pumps (minimum effective dose: 1.3 micromol/kg/day). Continuous infusion of (-)-nicotine produced comparable improvement in the spatial discrimination water maze performance of septal-lesioned rats, but a 40-fold higher dose of (-)-nicotine was required (62 micromol/kg/day). Continuous infusion of ABT-089 to aged rats enhanced spatial learning in a standard Morris water maze, as indexed by spatial bias exhibited during a probe trial conducted after 4 days of training, but not when they were subsequently trained in a two-platform spatial discrimination water maze. The compound induced a small impairment in young rats on the standard water maze, but not on the two-platform task. A probe trial conducted after additional training in the standard water maze revealed no age or drug effects. ABT-089 did not affect performance of either the aged or young rats during inhibitory (passive) avoidance training. Also, continuous infusion of ABT-089 did not affect responses to acoustic startle or prepulse inhibition of acoustic startle in young, aged or septal-lesioned rats and did not affect locomotor activity in either sham-lesioned or septal-lesioned rats. In monkeys, acute administration of ABT-089 modestly improved the delayed matching-to-sample performance of mature, adult monkeys and more robustly improved performance in aged monkeys. Improved performance in the aged monkeys was restricted to the longest

  2. Atomic resolution experimental phase information reveals extensive disorder and bound 2-methyl-2,4-pentanediol in Ca 2+ -calmodulin

    SciTech Connect

    Lin, Jiusheng; van den Bedem, Henry; Brunger, Axel T.; Wilson, Mark A.

    2016-01-01

    Calmodulin (CaM) is the primary calcium signaling protein in eukaryotes and has been extensively studied using various biophysical techniques. Prior crystal structures have noted the presence of ambiguous electron density in both hydrophobic binding pockets of Ca2+-CaM, but no assignment of these features has been made. In addition, Ca2+-CaM samples many conformational substates in the crystal and accurately modeling the full range of this functionally important disorder is challenging. In order to characterize these features in a minimally biased manner, a 1.0 Å resolution single-wavelength anomalous diffraction data set was measured for selenomethionine-substituted Ca2+-CaM. Density-modified electron-density maps enabled the accurate assignment of Ca2+-CaM main-chain and side-chain disorder. These experimental maps also substantiate complex disorder models that were automatically built using low-contour features of model-phased electron density. Furthermore, experimental electron-density maps reveal that 2-methyl-2,4-pentanediol (MPD) is present in the C-terminal domain, mediates a lattice contact between N-terminal domains and may occupy the N-terminal binding pocket. The majority of the crystal structures of target-free Ca2+-CaM have been derived from crystals grown using MPD as a precipitant, and thus MPD is likely to be bound in functionally critical regions of Ca2+-CaM in most of these structures. The adventitious binding of MPD helps to explain differences between the Ca2+-CaM crystal and solution structures and is likely to favor more open conformations of the EF-hands in the crystal.

  3. Design and construction of new potentiometric sensors for determination of Al3+ ion based on (Z)-2-(2-methyl benzylidene)-1-(2,4-dinitrophenyl) hydrazine.

    PubMed

    Mizani, F; Salmanzadeh Ardabili, S; Ganjaliab, M R; Faridbod, F; Payehghadr, M; Azmoodeh, M

    2015-04-01

    (Z)-2-(2-methyl benzylidene)-1-(2,4-dinitrophenyl) hydrazine (L) was used as an active component of PVC membrane electrode (PME), coated graphite electrode (CGE) and coated silver wire electrode (CWE) for sensing Al(3+) ion. The electrodes exhibited linear Nernstian responses to Al(3+) ion in the concentration range of 1.0×10(-6) to 1.0×10(-1)M (for PME, LOD=8.8×10(-7)M), 5.5×10(-7) to 2.0×10(-1)M (for CWE, LOD=3.3×10(-7)M) and 1.5×10(-7) to 1.0×10(-1)M (for CGE, LOD=9.2×10(-8)M). The best performances were observed with the membranes having the composition of L:PVC:NPOE:NaTPB in the ratio of 5:35:57:3 (w/w; mg). The electrodes have a response time of 6s and an applicable pH range of 3.5-9.1. The sensors have a lifetime of about 15weeks and exhibited excellent selectivity over a number of mono-, bi-, and tri-valent cations including alkali, alkaline earth metal, heavy and transition metal ions. Analytical utility of the proposed sensor has been further tested by using it as an indicator electrode in the potentiometric titration of Al(3+) with EDTA. The electrode was also successfully applied for the determination of Al(3+) ion in real and pharmaceutical samples. PMID:25687018

  4. The metabotropic glutamate receptor subtype 5 antagonist fenobam is analgesic and has improved in vivo selectivity compared with the prototypical antagonist 2-methyl-6-(phenylethynyl)-pyridine.

    PubMed

    Montana, Michael C; Cavallone, Laura F; Stubbert, Kristi K; Stefanescu, Andrei D; Kharasch, Evan D; Gereau, Robert W

    2009-09-01

    Metabotropic glutamate receptor subtype 5 (mGlu5) has been demonstrated to play a role in the modulation of numerous nociceptive modalities. When administered via peripheral, intrathecal, or systemic routes, mGlu5 antagonists have analgesic properties in a variety of preclinical pain models. Despite a wealth of data supporting the use of mGlu5 antagonists to treat pain, studies have been limited to preclinical animal models due to a lack of mGlu5 antagonists that are approved for use in humans. It has been demonstrated previously that fenobam [N-(3-chlorophenyl)-N'-(4,5-dihydro-1-methyl-4-oxo-1H-imidazole-2-yl)urea], an anxiolytic shown to be safe and effective in human trials, is a selective and potent noncompetitive antagonist of mGlu5 (J Pharmacol Exp Ther 315:711-721, 2005). Here, we report a series of studies aimed at testing whether fenobam, similar to the prototypical mGlu5 antagonist 2-methyl-6-(phenylethynyl)-pyridine (MPEP), has analgesic properties in mice. We show that fenobam reduces formalin-induced pain behaviors and relieves established inflammation-induced thermal hypersensitivity in mice. Similar results were seen with MPEP. Administration of fenobam resulted in an increase in locomotor activity in the open-field task but did not impair performance on the accelerating Rotarod. Analysis of brain and plasma fenobam levels indicated that fenobam is rapidly concentrated in brain after intraperitoneal administration in mice but is essentially cleared from circulation within 1 h after injection. Fenobam had no analgesic effect in mGlu5 knockout mice, whereas the prototypical antagonist MPEP retained significant analgesic efficacy in mGlu5 knockouts. These results demonstrate that fenobam is analgesic in mice and has an improved in vivo selectivity for mGlu5 over MPEP. PMID:19515968

  5. In vitro activities of 3-hydroxy-1,5,6-trimethoxy-2-methyl-9,10-anthraquinone against non-small cell lung carcinoma.

    PubMed

    Feng, Shi-Xiu; Guan, Qiunong; Chen, Tao; Du, Caigan

    2012-07-01

    Medicinal herbs are the preferred candidates for drug discovery against human diseases including cancer. The roots of Prismatomeris connata have been used in traditional herbal medicine to treat many health problems, particularly pneumoconiosis. This study was to test the anti-tumor activity of 3-hydroxy-1,5,6-trimethoxy-2-methyl-9,10-anthraquinone (PCON6), a major anthraquinone derivative from C. connata, against lung cancer. Cell viability in cultures was assessed by MTT assay. Cell death or apoptosis was determined with annexin-V and 7-aminoactinomycin D staining. Cell cycle was analyzed by both propidium iodide DNA staining and BrdU incorporation assay. Here we showed that in a panel of fifteen different tumor cells lines, a group of four non-small cell lung carcinoma (NSCLC) cell lines exhibited a relatively higher sensitivity to PCON6 growth inhibition than the rest of most non-lung cancer cell lines (p = 0.0461). Further studies demonstrated that the suppression of NSCLC H520 cell growth by PCON6 was associated with its induction of apoptosis at 20 μM (p = 0.0008), and of cell accumulation at S phase cell cycle (p < 0.05) that was further supported by a decrease in cdc2 protein expression. This preliminary study suggests that natural compound PCON6 has relatively selective cytotoxicity against NSCLC growth and represent a concept of developing a novel drug therapy specific for NSCLC based on the roots of C. connata or PCON6. PMID:22864748

  6. Leaf-Level Controls Over Emissions of Methanol and 2-Methyl-3-buten-2-ol, Oxygenated VOC With Different Production Mechanisms and Solubilities.

    NASA Astrophysics Data System (ADS)

    Harley, P. C.; Greenberg, J. P.; Guenther, A. B.

    2002-12-01

    Oxygenated VOC fluxes were investigated in leaves of deciduous trees and grasses, and needles of conifers, using a temperature-controlled leaf cuvette and a proton transfer reaction mass spectrometer. Two alcohols, 2-methyl-3-buten-2-ol (MBO) and methanol, emitted by these plants, illustrate two contrasting patterns of oxygenated VOC emissions. MBO is restricted to a small section of the genus Pinus, and is maximal in mature needles. Methanol production appears to be ubiquitous among higher plants, associated with demethylation of pectin during cell wall maturation, and emissions are therefore maximal during rapid leaf growth, decreasing in mature leaves. Although emissions of both compounds respond to variation in leaf temperature and incident light, the nature of the control is quite different. Production and emission of MBO are tightly coupled, and leaf pools are small. Light and temperature affect emissions directly through their effect on production which ceases rapidly in the dark. Effects of light and temperature on production of methanol are unknown, although emissions, and presumably production, continue through the night at reduced rates. Effects of light and temperature on methanol emission are indirect, through their effects on stomatal conductance and evapotranspiration. Data will be presented to justify a conceptual model in which methanol released in the demethylation of pectin partitions into the gas and liquid phase according to Henry's Law. Gas phase methanol is then emitted through the stomata. However, methanol emissions correlate more strongly with rates of evapotranspiration than with stomatal conductance, suggesting that much of the methanol is released from the dissolved pool along with the transpiration stream. At night, when stomatal conductance is low, and assuming constant production, gas phase concentrations increase, and the size of the aqueous pool increases in response. This aqueous pool then empties rapidly upon stomatal opening

  7. A comparative study on vibrational, conformational and electronic structure of 1,2-dimethyl-5-nitroimidazole and 2-methyl-5-nitroimidazole

    NASA Astrophysics Data System (ADS)

    Arjunan, V.; Ravindran, P.; Santhanam, R.; Raj, Arushma; Mohan, S.

    2012-11-01

    The FTIR and FT-Raman spectra of 1,2-dimethyl-5-nitroimidazole and 2-methyl-5-nitroimidazole have been recorded in the regions 4000-400 and 4000-100 cm-1, respectively. The conformational analyses were performed and the energies of the different possible conformers were determined. The geometry of different conformers of the compounds were optimised with B3LYP and B3PW91 methods using 6-311++G∗∗ and aug-cc-pVTZ basis sets to characterise all stationary points as minima. The optimised structural parameters of the most stable conformer were used in the vibrational frequency calculations. The Raman activities were also determined with B3LYP method using 6-311++G∗∗ basis sets. The force constants obtained from the B3LYP/6-311++G∗∗ method have been utilised in the normal coordinate analysis. The temperature dependence of the thermodynamic properties heat capacity at constant pressure (Cp), entropy (S) and enthalpy change (ΔH0→T) for both the compounds were also determined by B3LYP/6-311++G∗∗ method. The total electron density and MESP surfaces of the molecules were constructed by NBO analysis using B3LYP/6-311++G∗∗ method to display electrostatic potential (electron + nuclei) distribution, molecular shape, size, and dipole moments of the molecule. The electronic properties HOMO and LUMO energies were measured. The influences of nitro and methyl groups on the skeletal modes have been investigated.

  8. Kinetic studies on the acid hydrolysis of the methyl ketoside of unsubstituted and O-acetylated N-acetylneuraminic acid

    PubMed Central

    Neuberger, A.; Ratcliffe, Wendy A.

    1973-01-01

    The hydrolysis of the model compound 2-O-methyl-4,7,8,9-tetra-O-acetyl-N-acetyl-α-d-neuraminic acid and neuraminidase (Vibrio cholerae) closely resembled that of the O-acetylated sialic acid residues of rabbit Tamm–Horsfall glycoprotein. This confirmed that O-acetylation was responsible for the unusually slow rate of acid hydrolysis of O-acetylated sialic acid residues observed in rabbit Tamm–Horsfall glycoprotein and their resistance to hydrolysis by neuraminidase. The first-order rate constant of hydrolysis of 2-methyl-N-acetyl-α-d-neuraminic acid by 0.05m-H2SO4 was 56-fold greater than that of 2-O-methyl-4,7,8,9-tetra-O-acetyl-N-acetyl -α-d-neuraminic acid. Kinetic studies have shown that in the pH range 1.00–3.30, the observed rate of hydrolysis of 2-methyl-N-acetyl-α-d-neuraminic acid can be attributed to acid-catalysed hydrolysis of the negatively charged CO2− form of the methyl ketoside. PMID:4748825

  9. Lipase-catalyzed synthesis of fatty acid amide (erucamide) using fatty acid and urea.

    PubMed

    Awasthi, Neeraj Praphulla; Singh, R P

    2007-01-01

    Ammonolysis of fatty acids to the corresponding fatty acid amides is efficiently catalysed by Candida antartica lipase (Novozym 435). In the present paper lipase-catalysed synthesis of erucamide by ammonolysis of erucic acid and urea in organic solvent medium was studied and optimal conditions for fatty amides synthesis were established. In this process erucic acid gave 88.74 % pure erucamide after 48 hour and 250 rpm at 60 degrees C with 1:4 molar ratio of erucic acid and urea, the organic solvent media is 50 ml tert-butyl alcohol (2-methyl-2-propanol). This process for synthesis is economical as we used urea in place of ammonia or other amidation reactant at atmospheric pressure. The amount of catalyst used is 3 %. PMID:17898456

  10. Chlorinated phenoxyacetic acids and chlorophenols in the modified Allium test.

    PubMed

    Fiskesjö, G; Lassen, C; Renberg, L

    1981-03-15

    The chlorinated phenoxyacetic acids 2-methyl-4-chlorophenoxyacetic acid (MCPA), 2,4-dichlorophenoxyacetic acid (2,4-D), 2,4,5-trichlorophenoxyacetic acid (2,4,5-T) and 2,4,5-T butoxyethyl ester and the chlorophenols 2,4-dichlorophenol and 2,4,5-trichlorophenol were tested for genotoxicity in the modified Allium test, which is based on exposure to the test chemicals of growing onions. The mean length of growing roots were measured and chromosome damage was recorded. Of the substances tested, MCPA was the most toxic and the chlorophenoxyacetic acids were more toxic than the chlorophenols. The lower threshold values for growth retardation were below 0.1 ppm for the acids, approx. at 0.1 ppm for the ester and less than 5 ppm for the phenols. Though a monocotyledon, Allium cepa was sensitive enough to respond to even low concentrations of these dicotyledon-selecting pesticides. PMID:7460089

  11. Ternary Copper(II) Complexes With Indomethacin, a Potent Non-Steroidal Antiinflammatory Drug. Crystal Structure of Bis (Dimethylformamide)-Tetrakis[1-(4-Chlorobenzoyl)-5-Methoxy-2-Methyl-1-H-Indole-3-Acetato]Dicopper(II). Antiinflammatory Properties and Prevention of Gastrointestinal Side Effects by Nanocapsules

    PubMed Central

    Guessous, Fadila; Daran, Jean-Claude; Viossat, Bernard; Morgant, Georges; Labouze, Xavier; Leroy, Anne Laure; Roch-Arveiller, Monique

    1998-01-01

    Two ternary copper(ll) complexes of indomethacin [1-(4-chlorobenzoyl)-5-methoxy-2- methyl-1-H-indole-3-acetic acid] called hereafter lndo, were prepared and characterized by single crystal X-ray diffraction. The first complex Cu2(Indo)4(DMF)2 I crystallizes in space group P-1 (a = 10.829(2), b = 13.379(2), c = 16.491(3) Å; α = 105.58(2), β = 101.06(2), γ = 106.96(2)°; V= 2104.6(6) Å3, Z= 1). The title molecule is a centrosymmetric binuclear complex, with Cu atoms bridged by the carboxylate moieties of four indomethacinate ligands. The four nearest O atoms around each Cu atom form a square planar arrangement with the square pyramidal coordination completed by the O atom of N,N′-dimethylformamide. Daily administration for seven days of 1 mg/kg of indomethacin, I and I encapsulated into liposomes induces a weak inflammation of rat gastrointestinal tract. I was less inflammatory than indomethacin but the better protection was brought by encapsulation of the compound. This might be of interest in sustained therapies of chronic inflammatory diseases. PMID:18475870

  12. Crystal structure of bis­(2-methyl-1H-imidazole-κN 3)(meso-tetra-p-tol­ylporphyrinato-κ4 N)iron(III) perchlorate tetra­hydro­furan sesquisolvate

    PubMed Central

    Sun, Wenyan; Li, Jianfeng

    2016-01-01

    In the title compound, [Fe(C48H36N4)(C4H6N2)2]ClO4·1.5C4H8O, the iron(III) metal is coordinated in a distorted octa­hedral geometry by four pyrrole N atoms of the porphyrin ligand in the equatorial plane and two N atoms of 2-methyl­imidazole ligands in the axial sites. The complex has a highly ruffled porphyrin core with mean absolute core-atom displacements C a, C b, C m and C av of 0.25 (5), 0.17 (12), 0.432 (16) and 0.25 (13) Å, respectively. One of the four phenyl groups of the porphyrin is disordered over two sets of sites with refined occupancy ratio of 0.718 (7):0.282 (7). The mean Fe—Np (Np is a porphyrin N atom) bond length [1.975 (9) Å] indicates the low-spin state of the iron atom. The two 2-methyl­imidazole ligands are nearly perpendicular and form a dihedral angle of 86.93 (10)°. The dihedral angles between the 2-methyl­imidazole ligands and the closest Fe—Np vector are 38.04 (9) and 35.00 (7)°. In the crystal, the complex cations inter­act with the perchlorate anions through N—H⋯O hydrogen bonds, forming chains running parallel to [110]. PMID:27536394

  13. Crystal structure of bis-(2-methyl-1H-imidazole-κN (3))(meso-tetra-p-tol-ylporphyrinato-κ(4) N)iron(III) perchlorate tetra-hydro-furan sesquisolvate.

    PubMed

    Sun, Wenyan; Li, Jianfeng

    2016-08-01

    In the title compound, [Fe(C48H36N4)(C4H6N2)2]ClO4·1.5C4H8O, the iron(III) metal is coordinated in a distorted octa-hedral geometry by four pyrrole N atoms of the porphyrin ligand in the equatorial plane and two N atoms of 2-methyl-imidazole ligands in the axial sites. The complex has a highly ruffled porphyrin core with mean absolute core-atom displacements C a, C b, C m and C av of 0.25 (5), 0.17 (12), 0.432 (16) and 0.25 (13) Å, respectively. One of the four phenyl groups of the porphyrin is disordered over two sets of sites with refined occupancy ratio of 0.718 (7):0.282 (7). The mean Fe-Np (Np is a porphyrin N atom) bond length [1.975 (9) Å] indicates the low-spin state of the iron atom. The two 2-methyl-imidazole ligands are nearly perpendicular and form a dihedral angle of 86.93 (10)°. The dihedral angles between the 2-methyl-imidazole ligands and the closest Fe-Np vector are 38.04 (9) and 35.00 (7)°. In the crystal, the complex cations inter-act with the perchlorate anions through N-H⋯O hydrogen bonds, forming chains running parallel to [110]. PMID:27536394

  14. 2-Chloro-4-[[(1R,2R)-2-hydroxy-2-methyl-cyclopentyl]amino]-3-methyl-benzonitrile: A Transdermal Selective Androgen Receptor Modulator (SARM) for Muscle Atrophy.

    PubMed

    Saeed, Ashraf; Vaught, Grant M; Gavardinas, Kostas; Matthews, Donald; Green, Jonathan E; Losada, Pablo Garcia; Bullock, Heather A; Calvert, Nathan A; Patel, Nita J; Sweetana, Stephanie A; Krishnan, Venkatesh; Henck, Judith W; Luz, John G; Wang, Yong; Jadhav, Prabhakar

    2016-01-28

    A transdermal SARM has a potential to have therapeutic benefit through anabolic activity in muscle while sparing undesired effects of benign prostate hyperplasia (BPH) and liver-mediated decrease in HDL-C. 2-Chloro-4-[(2-hydroxy-2-methyl-cyclopentyl)amino]-3-methyl-benzonitrile 6 showed the desired muscle and prostate effects in a preclinical ORX rat model. Compound 6 had minimal effect on HDL-C levels in cynomolgus monkeys and showed human cadaver skin permeability, thus making it an effective tool for proof-of-concept studies in a clinical setting. PMID:26683992

  15. 5-Meth­oxy-2,2-dimethyl-6-[(2E)-2-methyl­but-2-eno­yl]-10-phenyl-2H,8H-pyrano[2,3-f]chromen-8-one (calophyllolide)

    PubMed Central

    Kalyanaraman, L.; Mohan Kumar, R.; Vishweshwar, Peddy; Pichai, R.; Narasimhan, S.

    2010-01-01

    The title compound, C26H24O5, was isolated from calophyllum inophyllum seeds. In the mol­ecule, the phenyl and 2-methyl­but-2-enoyl groups are almost orthogonal to the chromene fragment [C—C—C—C torsion angles = 81.4 (3) and −90.1 (2)°, respectively]. In the crystal packing, centrosymmetrically related mol­ecules are linked by C—H⋯O contacts into dimers, which are connected via further C—H⋯O inter­actions into a double chain along [010]. PMID:21579166

  16. 5-Meth-oxy-2,2-dimethyl-6-[(2E)-2-methyl-but-2-eno-yl]-10-phenyl-2H,8H-pyrano[2,3-f]chromen-8-one (calophyllolide).

    PubMed

    Kalyanaraman, L; Mohan Kumar, R; Vishweshwar, Peddy; Pichai, R; Narasimhan, S

    2010-01-01

    The title compound, C(26)H(24)O(5), was isolated from calophyllum inophyllum seeds. In the mol-ecule, the phenyl and 2-methyl-but-2-enoyl groups are almost orthogonal to the chromene fragment [C-C-C-C torsion angles = 81.4 (3) and -90.1 (2)°, respectively]. In the crystal packing, centrosymmetrically related mol-ecules are linked by C-H⋯O contacts into dimers, which are connected via further C-H⋯O inter-actions into a double chain along [010]. PMID:21579166

  17. Surface tension of binary mixtures of water + N-methyldiethanolamine and ternary mixtures of this amine and water with monoethanolamine, diethanolamine, and 2-amino-2-methyl-1-propanol from 25 to 50 C

    SciTech Connect

    Alvarez, E.; Rendo, R.; Sanjurjo, B.; Sanchez-Vilas, M.; Navaza, J.M.

    1998-11-01

    The surface tension of aqueous solutions of N-methyldiethanolamine and diethanolamine + N-methyldiethanolamine, monoethanolamine + N-methyldiethanolamine and 2-amino-2-methyl-1-propanol + N-methyldiethanolamine was measured at temperatures from 25 C to 50 C. For binary mixtures the concentration range was 0--50 mass % N-methyldiethanolamine, and for the tertiary mixtures the concentration range for each amine was 0--50 mass %. The experimental values were correlated with temperature and mole fraction. The maximum deviation in both cases was always less than 0.5%.

  18. Solubility of carbon dioxide in aqueous solutions of 2-amino-2-methyl-1-propanol and N-methyldiethanolamine and their mixtures in the temperature range of 313 to 353 K and pressures up to 2.7 MPa

    SciTech Connect

    Silkenbaeumer, D.; Lichtenthaler, R.N.; Rumpf, B.

    1998-08-01

    The solubility of carbon dioxide in aqueous solutions containing 2-amino-2-methyl-1-propanol (AMP) was measured in the temperature range from 313 to 353 K at total pressures up to 2.7 MPa using an analytical method. A model taking into account chemical reactions in the liquid phase as well as physical interactions is used to correlate the new data. To test the predictive capability of the model, the solubility of carbon dioxide in an aqueous solution containing AMP and N-methyldiethanolamine (MDEA) was measured at 313 K. Experimental results are reported and compared to literature data and calculations.

  19. (E)-4-(5-Hydr­oxy-2-methyl­benzyl­idene­amino)-1,5-dimethyl-2-phenyl-1H-pyrazol-3(2H)-one

    PubMed Central

    Zheng, Yun-Fa; Yang, Ming-Hua

    2008-01-01

    The title compound, C19H19N3O2, is a Schiff base compound derived from 4-amino­anti­pyrine and 5-hydr­oxy-2-methyl­benzaldehyde. The mol­ecule adopts a trans configuration about the central C=N bond. There is an intra­molecular O—H⋯N hydrogen bond. Futhermore, weak C—H⋯O hydrogen bonds lead to the formation of a chain developing parallel to the b axis. PMID:21201212

  20. 21 CFR 73.3100 - 1,4-Bis[(2-hydroxyethyl)amino]-9,10-anthracenedione bis(2-propenoic)ester copolymers.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... the contact lens material. (b) Uses and restrictions. (1) The substances listed in paragraph (a) of... Cosmetic Act (the act) with respect to the contact lens made from the color additives. (c) Labeling....

  1. Hepatic alpha-oxidation of phytanic acid. A revised pathway.

    PubMed

    Van Veldhoven, P P; Mannaerts, G P; Casteels, M; Croes, K

    1999-01-01

    Synthetic 3-methyl-branched chain fatty acids were used to decipher the breakdown of phytanic acid. Based on results obtained in intact or permeabilized rat hepatocytes, rat liver homogenates or subcellular fractions, a revised alpha-oxidation pathway is proposed which appears to be functioning in man as well. In a first step, the 3-methyl-branched chain fatty acid is activated by an acyl-CoA synthetase. This reaction requires CoA, ATP and Mg2+. Subsequently, the acyl-CoA ester is hydroxylated at position 2 by a peroxisomal dioxygenase. This step is dependent on alpha-oxoglutarate, ascorbate (or glutathione), Fe2+ and O2. The 2-hydroxy-3-methylacyl-CoA intermediate is cleaved by a peroxisomal lyase to formyl-CoA and a 2-methyl-branched fatty aldehyde. Formyl-CoA is (partly enzymically) hydrolyzed to formate, which is then converted, most likely in the cytosol, to CO2. In the presence of NAD+, the aldehyde is dehydrogenated to a 2-methyl-branched fatty acid, presumably by a peroxisomal aldehyde dehydrogenase. This acid can--after activation--be degraded via a D-specific peroxisomal beta-oxidation system. PMID:10709654

  2. Kinetic resolution of acids in acylation reactions in the presence of chiral tertiary amines

    SciTech Connect

    Potapov, V.M.; Dem'yanovich, V.M.; Khlebnikov, V.A.

    1988-07-10

    Asymmetric synthesis has now become an important method for the production of optically active compounds, and its most attractive form is asymmetric catalysis. This work was devoted to an investigation into asymmetric catalysis with chiral tertiary amines in acylation reactions. During the acylation of alcohols and amines by the action of racemic 2-phenylpropionic and 2-methyl-3-phenylpropionic acids in the presence of S-nicotine the initial acids are resolved kinetically. The (R)-2-phenylpropionic acid obtained in this way had an optical purity of 0.5-1.5%.

  3. Novel light-conversion hybrids of SBA-16 functionalized with rare earth (Eu3+, Nd3+, Yb3+) complexes of modified 2-methyl-9-hydroxyphenalenone and 1,10-phenanthroline

    NASA Astrophysics Data System (ADS)

    Gu, Yan-Jing; Yan, Bing; Qiao, Xiao-Fei

    2013-03-01

    Novel rare earth complex-functionalized mesoporous SBA-16-type hybrid materials are synthesized by the co-condensation of modified 2-methyl-9-hydroxyphenalenone (MHPOSi), from modified 3-(triethoxysilyl)-propyl isocyanate (TEPIC), and tetraethoxysilane (TEOS) in the presence of Pluronic F127 as a template. These inorganic-organic mesoporous hybrids are characterized by FT-IR spectra, small-angle X-ray diffraction (SAXRD), N2 adsorption-desorption measurements, thermal analysis and spectroscopy. Their photophysical properties, which show novel light conversion properties, are discussed in detail. The Eu3+ hybrid system shows ultraviolet excitation and visible emission, and the Nd+ and Yb3+ hybrids exhibit visible excitation and NIR emission.

  4. 2-Methyl-4-oxo-N-(4-oxo-2-phenyl substituted-1,3-thiazolidin-3-yl)-3,4-dihydroquinazoline-5-carboxamides--a new range of fluorescent whiteners: synthesis and photophysical characterization.

    PubMed

    Patil, Vikas S; Padalkar, Vikas S; Sekar, Nagaiyan

    2014-07-01

    Fluorescent quinazolinones were synthesized form ethyl 2-methyl-4-oxo-3,4-dihydroquinazoline -5-carboxylate intermediate. The photophysical properties of the compounds were evaluated in DMF solvent. The experimental absorption and emission of the compounds were compared with the vertical excitation and emission obtained Density Functional Theory (DFT) and Time Dependent Density Functional Theory (TD-DFT) computation. Application of the fluorescent compounds as a fluorescent brightening agent was tested on polyester fiber. Changes in the electronic transition, energy levels, and orbital diagrams of quinazolin-4(3H)-one analogues were investigated using the DFT computations and were correlated with the experimental spectral data. The experimental absorption and emission wavelengths are in good agreement with those predicted using the DFT and TD-DFT. PMID:24849738

  5. Assignments of the vibrational spectra of 2,5-dimethyl-2,4-hexadiene, 4-methyl-1,3-pentadiene and (E)-2-methyl-1,3-pentadiene. Effect of the terminal and lateral methyl groups1

    NASA Astrophysics Data System (ADS)

    Aly, M. M. Abo; Baron, M. H.; Coulange, M. J.; Favrot, J.

    The complete assignment of the vibrational spectra of 2,5-dimethyl-2,4-hexadiene, 4-methyl-1,3-pentadiene and ( E)-2-methyl-1,3-pentadiene was obtained from a comparative analysis of their i.r. and Raman spectra (solid, liquid and gas) in the range 3200-50 cm -1. It is shown that particular vibrational motions strongly interact to give rise to very characteristic modes depending on the site of methyl substitution. The comparison of our results with those of analogous shorter and larger polyenes and polyenals allows us to discuss the various local coupled motions characteristic of unsubstituted (CHCH CH)CH and methyl substituted (CHC(CH 3)CH), ((CH 3) 2CCH) or (CH 3CHCH) fragments in polyenic chains.

  6. Novel GluN2B selective NMDA receptor antagonists: relative configuration of 7-meth-oxy-2-methyl-2,3,4,5-tetra-hydro-1H-3-benzazepin-1-ols.

    PubMed

    Tewes, Bastian; Frehland, Bastian; Fröhlich, Roland; Wünsch, Bernhard

    2016-05-01

    The title compounds, C22H29NO2 (3) and C22H29NO2 (4) [systematic names: (1S*,2R*)-7-meth-oxy-2-methyl-3-(4-phenyl-but-yl)-2,3,4,5-tetra-hydro-1H-3-benzazepin-1-ol and (1R*,2R*)-7-meth-oxy-2-methyl-3-(4-phenyl-but-yl)-2,3,4,5-tetra-hydro-1H-3-benzazepin-1-ol, are diastereomers with the relative configuration of the adjacent hydroxyl and methyl groups at the seven-membered azepine ring being trans in (3) and cis in (4). In the crystals the orientation of these groups is -anti-periplanar (3) and +syn-clinal (4). In both cases, the crystals studied proved to be of a racemic mixture, with relative configurations (R*,S*)-3 and (R*,R*)-4. In both compounds, the seven-membered azepine ring has a chair-like conformation, and the 4-phenyl-butyl side chain adopts a extended conformation in (R*,S*)-3, but a twisted conformation in (R*,R*)-4. In the crystal of (S*,R*)-3, mol-ecules are linked via C-H⋯O hydrogen bonds, forming slabs parallel to the ac plane. In the crystal of (R*,R*)-4, mol-ecules are linked via O-H⋯N hydrogen bonds, forming chains propagating along the c-axis direction. The chains are linked by C-H⋯O hydrogen bonds, forming slabs parallel to the ac plane. PMID:27308019

  7. Novel GluN2B selective NMDA receptor antagonists: relative configuration of 7-meth­oxy-2-methyl-2,3,4,5-tetra­hydro-1H-3-benzazepin-1-ols

    PubMed Central

    Tewes, Bastian; Frehland, Bastian; Fröhlich, Roland; Wünsch, Bernhard

    2016-01-01

    The title compounds, C22H29NO2 (3) and C22H29NO2 (4) [systematic names: (1S*,2R*)-7-meth­oxy-2-methyl-3-(4-phenyl­but­yl)-2,3,4,5-tetra­hydro-1H-3-benzazepin-1-ol and (1R*,2R*)-7-meth­oxy-2-methyl-3-(4-phenyl­but­yl)-2,3,4,5-tetra­hydro-1H-3-benzazepin-1-ol, are diastereomers with the relative configuration of the adjacent hydroxyl and methyl groups at the seven-membered azepine ring being trans in (3) and cis in (4). In the crystals the orientation of these groups is −anti-periplanar (3) and +syn-clinal (4). In both cases, the crystals studied proved to be of a racemic mixture, with relative configurations (R*,S*)-3 and (R*,R*)-4. In both compounds, the seven-membered azepine ring has a chair-like conformation, and the 4-phenyl­butyl side chain adopts a extended conformation in (R*,S*)-3, but a twisted conformation in (R*,R*)-4. In the crystal of (S*,R*)-3, mol­ecules are linked via C—H⋯O hydrogen bonds, forming slabs parallel to the ac plane. In the crystal of (R*,R*)-4, mol­ecules are linked via O—H⋯N hydrogen bonds, forming chains propagating along the c-axis direction. The chains are linked by C—H⋯O hydrogen bonds, forming slabs parallel to the ac plane. PMID:27308019

  8. Behavioral and electrophysiological responses of Aedes albopictus to certain acids and alcohols present in human skin emanations.

    PubMed

    Guha, Lopamudra; Seenivasagan, T; Iqbal, S Thanvir; Agrawal, O P; Parashar, B D

    2014-10-01

    Human skin emanations attract hungry female mosquitoes toward their host for blood feeding. In this study, we report the flight orientation and electroantennogram response of Aedes albopictus females to certain unsaturated acids and alcohols found in human skin. In the Y-tube olfactometer, odors of lactic acid and 2-methyl-3-pentanol attracted 54-65% of Ae. albopictus females at all doses in a dose-dependent manner. However, at the highest dose (10(-2) g), the acids repelled 40-45% females. Attractancy (ca. 62-68%) at lower doses and repellency (ca. 30-45%) at higher doses were recorded for 3-methyl-3-pentanol and 1-octen-3-ol, while 5-hexen-1-ol, cis-2-hexen-1-ol, and trans 2-hexen-1-ol odor repelled ca. 55-65% of Ae. albopictus females at all doses. Antenna of female Ae. albopictus exhibited a dose-dependent EAG response up to 10(-3) g of L-lactic acid, trans-2-methyl-2-pentenoic acid, 2-octenoic acid, trans-2-hexen-1-ol and 1-octen-3-ol stimulations; however, the highest dose (10(-2) g) caused a little decline in the EAG response. EAG response of 9-10-fold was elicited by lactic acid, 2-octenoic acid, trans-2-hexenoic acid, and 3-methyl-3-pentanol, while cis-2-hexen-1-ol and trans-2-methyl pentenoic acid elicited 1-5-fold responses compared to solvent control. A blend of attractive compounds could be utilized in odor-baited trap for surveillance and repellent molecules with suitable formulation could be used to reduce the biting menace of mosquitoes. PMID:25049052

  9. 76 FR 35886 - Certain New Chemicals; Receipt and Status Information

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-06-20

    ... leather. P-11-0368 5/11/2011 8/8/2011 CBI (G) Lamination adhesive.... (G) IPDI modified polyester resin. P.../21/2011 (G) Polyester type polyurethane resin. P-11-0164 5/9/2011 5/5/2011 (G) 2-propenoic acid, 2.../ importer Use Chemical date date P-11-0341 4/25/2011 7/23/2011 CBI (S) One resin component for (G)...

  10. 77 FR 76029 - Certain New Chemicals; Receipt and Status Information

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-12-26

    ... 8/11/2011 (G) Ipdi modified polyester resin. P-11-0557 11/27/2012 11/2/2012 (G) 2-propenoic acid, 2... 11/20/2012 11/1/2012 (G) Polyester type polyurethane resin. P-12-0272 11/6/2012 11/2/2012 (S) 1,3.... P-13-0090 11/1/2012 1/29/2013 Cytec Industries, (G) Resin for non- (G) Alkenenitrile,...

  11. 40 CFR 721.4486 - Propanoic acid, 2-methyl-, (1R,2R,4R)-1,7,7-trimethylbicyclo[2.2.1]hept-2-yl ester, rel-.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...,4R)-1,7,7-trimethylbicyclo hept-2-yl ester, rel-. (a) Chemical substance and significant new uses...)-1,7,7-trimethylbicyclo hept-2-yl ester, rel-. 721.4486 Section 721.4486 Protection of Environment...,7-trimethylbicyclo hept-2-yl ester, rel- (PMNs P-98-0497 and P-98-0509; CAS No. 85586-67-0)...

  12. Crystal and molecular structures of twelve salts from isopropylamine and different organic acids

    NASA Astrophysics Data System (ADS)

    Wen, Xianhong; Zhang, Huan; Xu, Kai; Sun, JiaHui; Ye, Jiaying; Jin, Shouwen; Wang, Daqi

    2015-08-01

    Twelve isopropylamine derived supramolecular complexes isopropylamine: (m-toluic acid) [(Hipa)+ ṡ (mtua-), mtua- = m-toluate] (1), isopropylamine: (p-toluic acid) [(Hipa)+ ṡ (ptua-), ptua- = p-toluate] (2), isopropylamine: (p-methoxybenzoic acid) [(Hipa)+ ṡ (pmba-), pmba- = p-methoxybenzoate] (3), (isopropylamine): (3,4-methylenedioxybenzoic acid) [(Hipa)+ ṡ (mba)-, mba = 3,4-methylenedioxybenzoate] (4), (isopropylamine): (2-methyl-2-phenoxypropanoic acid) [(Hipa)+ ṡ (mpa-), mpa- = 2-methyl-2-phenoxypropionate] (5), (isopropylamine): (4-chlorophenoxyacetic acid) [(Hipa)+ ṡ (cpa-), cpa- = 4-chlorophenoxyacetate] (6), (isopropylamine): (3,5-dinitrobenzoic acid) [(Hipa)+ ṡ (dnba-), dnba- = 3,5-dinitrobenzoate] (7), (isopropylamine): (2-furoic acid) [(Hipa)+ ṡ (fura-), fura- = 2-furoate] (8), (isopropylamine): (1-hydroxy-2-naphthoic acid) [(Hipa)+ ṡ (hna), hna = 1-hydroxy-2-naphthoate] (9), (isopropylamine): (4-nitrophthalic acid) [(Hipa)2+ ṡ (npa2-), npa2- = 4-nitrophthalate] (10), (isopropylamine)2: (2,5-bis-isopropylcarbamoyl-terephthalic acid): 2H2O [(Hipa)2+ ṡ (bta2-) ṡ 2H2O, bta2- = 2,5-bis-isopropylcarbamoyl-terephthalate] (11), and (isopropylamine)2: (1,5-naphthalenedisulfonic acid) [(Hipa)2+ ṡ (nds2-), nds2- = 1,5-naphthalenedisulfonate] (12) were synthesized and structurally characterized by X-ray crystallography. All supramolecular architectures of 1-12 involve extensive classical hydrogen bonds as well as other non-covalent interactions. The results presented herein indicate that the strength and directionality of the Nsbnd H⋯O, Osbnd H⋯O, and Osbnd H⋯S hydrogen bonds between the acidic components and isopropylamine are sufficient to bring about the formation of binary organic salts. The role of weak and strong non-covalent interactions in the crystal packing is ascertained. These weak interactions combined, the complexes 1-12 displayed 1D-3D framework structure.

  13. Amino acids

    MedlinePlus

    Amino acids are organic compounds that combine to form proteins . Amino acids and proteins are the building blocks of life. When proteins are digested or broken down, amino acids are left. The human body uses amino acids ...

  14. Study of the Effect of UV Radiation on the Decomposition of 4-Chloro-2-Methylphenoxyacetic Acid

    NASA Astrophysics Data System (ADS)

    Tchaikovskaya, O. N.; Karetnikova, E. A.; Sokolova, I. V.; Mayer, G. V.

    2013-12-01

    The influence of UV radiation wavelength on the disappearance kinetics of 4-chloro-2-methylphenoxyacetic acid (MCPA) in the presence of activated sludge and humic acids has been examined. Variations in the kinetic curves of MCPA removal in the presence of humic acids were determined from results on accumulation of carbon dioxide gas. Spectral-luminescence and chromato-mass-spectrometry data reveal the presence in the medium of the biotransformation product 2-methyl-4-chlorophenol, which is utilized after 14 days. Addition of humic acids, on the one hand, reduced the rates of subsequent biodecomposition of MCPA. On the other hand, in the process of transformation of the herbicide in the presence of humic acids a photobioproduct was detected which does not contain chlorine: 2-methylphenoxyacetic acid.

  15. Crystal structure of (+)-methyl (E)-3-[(2S,4S,5R)-2-amino-5-hy-droxy-meth-yl-2-tri-chloro-methyl-1,3-dioxolan-4-yl]-2-methyl-prop-2-enoate.

    PubMed

    Oishi, Takeshi; Yasushima, Daichi; Yuasa, Kihiro; Sato, Takaaki; Chida, Noritaka

    2016-03-01

    In the title compound, C10H14Cl3NO5, the five-membered dioxolane ring adopts an envelope conformation. The C atom at the flap, which is bonded to the hy-droxy-methyl substituent, deviates from the mean plane of other ring atoms by 0.357 (5) Å. There are two intra-molecular hydrogen bonds (O-H⋯N and N-H⋯O) between the hy-droxy and amino groups, so that O- and N-bound H atoms involved in these hydrogen bonds are each disordered with equal occupancies of 0.50. The methyl 2-methyl-prop-2-enoate substituent also shows a disordered structure over two sets of sites with refined occupancies of 0.482 (5) and 0.518 (5). In the crystal, mol-ecules are connected into a dimer by an O-H⋯O hydrogen bond. The dimers are further linked by N-H⋯O, C-H⋯N and C-H⋯O inter-actions, extending a sheet structure parallel to ([Formula: see text]01). PMID:27006804

  16. Screening of High-Level 4-Hydroxy-2 (or 5)-Ethyl-5 (or 2)-Methyl-3(2H)-Furanone-Producing Strains from a Collection of Gene Deletion Mutants of Saccharomyces cerevisiae

    PubMed Central

    Watanabe, Jun; Akao, Takeshi; Watanabe, Daisuke; Mogi, Yoshinobu; Shimoi, Hitoshi

    2014-01-01

    4-Hydroxy-2 (or 5)-ethyl-5 (or 2)-methyl-3(2H)-furanone (HEMF) is an important flavor compound that contributes to the sensory properties of many natural products, particularly soy sauce and soybean paste. The compound exhibits a caramel-like aroma and several important physiological activities, such as strong antioxidant activity. HEMF is produced by yeast species in soy sauce manufacturing; however, the enzymes involved in HEMF production remain unknown, hindering efforts to breed yeasts with high-level HEMF production. In this study, we identified high-level HEMF-producing mutants among a Saccharomyces cerevisiae gene deletion mutant collection. Fourteen deletion mutants were screened as high-level HEMF-producing mutants, and the ADH1 gene deletion mutant (adh1Δ) exhibited the maximum HEMF production capacity. Further investigations of the adh1Δ mutant implied that acetaldehyde accumulation contributes to HEMF production, agreeing with previous findings. Therefore, acetaldehyde might be a precursor for HEMF. The ADH1 gene deletion mutant of Zygosaccharomyces rouxii, which is the dominant strain of yeast found during soy sauce fermentation, also produces HEMF effectively, suggesting that acetaldehyde accumulation might be a benchmark for breeding industrial yeasts with excellent HEMF production abilities. PMID:25362059

  17. Screening of high-level 4-hydroxy-2 (or 5)-ethyl-5 (or 2)-methyl-3(2H)-furanone-producing strains from a collection of gene deletion mutants of Saccharomyces cerevisiae.

    PubMed

    Uehara, Kenji; Watanabe, Jun; Akao, Takeshi; Watanabe, Daisuke; Mogi, Yoshinobu; Shimoi, Hitoshi

    2015-01-01

    4-Hydroxy-2 (or 5)-ethyl-5 (or 2)-methyl-3(2H)-furanone (HEMF) is an important flavor compound that contributes to the sensory properties of many natural products, particularly soy sauce and soybean paste. The compound exhibits a caramel-like aroma and several important physiological activities, such as strong antioxidant activity. HEMF is produced by yeast species in soy sauce manufacturing; however, the enzymes involved in HEMF production remain unknown, hindering efforts to breed yeasts with high-level HEMF production. In this study, we identified high-level HEMF-producing mutants among a Saccharomyces cerevisiae gene deletion mutant collection. Fourteen deletion mutants were screened as high-level HEMF-producing mutants, and the ADH1 gene deletion mutant (adh1Δ) exhibited the maximum HEMF production capacity. Further investigations of the adh1Δ mutant implied that acetaldehyde accumulation contributes to HEMF production, agreeing with previous findings. Therefore, acetaldehyde might be a precursor for HEMF. The ADH1 gene deletion mutant of Zygosaccharomyces rouxii, which is the dominant strain of yeast found during soy sauce fermentation, also produces HEMF effectively, suggesting that acetaldehyde accumulation might be a benchmark for breeding industrial yeasts with excellent HEMF production abilities. PMID:25362059

  18. Structural, vibrational and DFT studies on 2-chloro-1H-isoindole-1,3(2H)-dione and 2-methyl-1H-isoindole-1,3(2H)-dione.

    PubMed

    Arjunan, V; Saravanan, I; Ravindran, P; Mohan, S

    2009-10-15

    The Fourier transform infrared (FTIR) and FT-Raman spectra of 2-chloro-1H-isoindole-1,3(2H)-dione and 2-methyl-1H-isoindole-1,3(2H)-dione have been measured in the range of 4000-400 and 4000-100 cm(-1), respectively. Complete vibrational assignment and analysis of the fundamental modes of the compounds were performed using the observed FTIR and FT-Raman data. The geometry was optimised without any symmetry constraints using the DFT/B3LYP method with 6-31G(d,p) and 6-311++G(d,p) basis sets. The vibrational frequencies determined experimentally are compared with those obtained theoretically from DFT gradient calculations employing the B3LYP/6-31G(d,p) and B3LYP/6-311++G(d,p) methods for the optimised geometry of the compounds. The structural parameters and normal modes of vibration obtained from DFT method are in good agreement with the experimental data. The force fields obtained from DFT method were utilised and the potential energy distributions of all the fundamental vibrations of the compounds were calculated. PMID:19660980

  19. Structural, vibrational and DFT studies on 2-chloro-1H-isoindole-1,3(2H)-dione and 2-methyl-1H-isoindole-1,3(2H)-dione

    NASA Astrophysics Data System (ADS)

    Arjunan, V.; Saravanan, I.; Ravindran, P.; Mohan, S.

    2009-10-01

    The Fourier transform infrared (FTIR) and FT-Raman spectra of 2-chloro-1H-isoindole-1,3(2H)-dione and 2-methyl-1H-isoindole-1,3(2H)-dione have been measured in the range of 4000-400 and 4000-100 cm -1, respectively. Complete vibrational assignment and analysis of the fundamental modes of the compounds were performed using the observed FTIR and FT-Raman data. The geometry was optimised without any symmetry constraints using the DFT/B3LYP method with 6-31G(d,p) and 6-311++G(d,p) basis sets. The vibrational frequencies determined experimentally are compared with those obtained theoretically from DFT gradient calculations employing the B3LYP/6-31G(d,p) and B3LYP/6-311++G(d,p) methods for the optimised geometry of the compounds. The structural parameters and normal modes of vibration obtained from DFT method are in good agreement with the experimental data. The force fields obtained from DFT method were utilised and the potential energy distributions of all the fundamental vibrations of the compounds were calculated.

  20. Identification of 2,5-dimethyl-4-hydroxy-3(2H)-furanone (DMHF) and 4-hydroxy-2(or 5)-ethyl-5(or 2)-methyl-3(2H)-furanone (HEMF) with DNA breaking activity in soy sauce.

    PubMed

    Li, X; Hiramoto, K; Yoshida, M; Kato, T; Kikugawa, K

    1998-04-01

    Components with DNA breaking activity in soy sauce were investigated. It was found that there were water soluble high molecular weight DNA breaking components in soy sauce. Two DNA breaking components in the ethyl acetate extract of soy sauce were identified as fragrant components, 2,5-dimethyl-4-hydroxy-3(2H)-furanone (DMHF) and 4-hydroxy-2(or 5)-ethyl-5(or 2)-methyl-3(2H)-furanone (HEMF), in addition to the previously characterized DNA breaking fragrant component 4-hydroxy-5-methyl-3(2H)-furanone (HMF) (Hiramoto et al., 1996b). Characterization of DNA breaking activity of HEMF was performed, and the mechanisms for the breaking were considered. HEMF cleaved the single strands of supercoiled pBR 322 DNA at pH 7.4 dose dependently and time dependently. DNA breaking was inhibited by superoxide dismutase, catalase, hydroxyl radical scavengers, spin trapping agents and metal chelators, and enhanced by Fe(III) ion. Electron spin resonance-spin trapping technique revealed the generation of hydroxyl radical. Hence, active oxygen species derived from interaction of HEMF with metal ions and oxygen participated in the cleavage. HEMF exhibited mutagenicity to Salmonella typhimurium TA100 without metabolic activation and induced micronucleated mouse peripheral reticulocytes. PMID:9651047

  1. Identification and characterization of a novel cross-link lesion in d(CpC) upon 365-nm irradiation in the presence of 2-methyl-1,4-naphthoquinone

    PubMed Central

    Liu, Zhenjiu; Gao, Yuan; Wang, Yinsheng

    2003-01-01

    We report the isolation and characterization for the first time of a cross-link lesion between two adjacent cytosines from the 2-methyl-1,4-naphthoquinone (menadione)-sensitized 365-nm irradiation of d(CpC). Electrospray ionization mass spectrometry (ESI-MS), tandem MS and 1H NMR results indicate that the cross-link occurs between the C5 carbon atom of one cytosine and the N4 nitrogen atom of the other cytosine. Furthermore, we synthesized d(CpC) with a 15N being incorporated on the amino group of either of the two cytosines. We then irradiated the two 15N-labeled dinucleoside monophosphates, isolated the cross-link products and characterized them by MS and multi-stage tandem MS. The latter results established unambiguously that the N4 nitrogen atom of the 3′-nucleobase is involved in the covalent bond formation between the two cytosines. This, in combination with two-dimensional nuclear Overhauser effect spectroscopy (NOESY) results, demonstrates that the cross-link arises from the formation of a covalent bond between the C5 carbon atom of the 5′ cytosine and the N4 nitrogen atom of the 3′ cytosine. We also show that the solution pH has a significant effect on the formation of the cross-link lesion, which supports that the deprotonation at the exocyclic amino group of cytosine cation radical is essential for the formation of the cross-link lesion. PMID:12954778

  2. Kinetics of the gas-phase reaction between ozone and three unsaturated oxygenated compounds: Ethyl 3,3-dimethyl acrylate, 2-methyl-2-pentenal and 6-methyl-5-hepten-2-one at atmospheric pressure

    NASA Astrophysics Data System (ADS)

    Gaona Colmán, Elizabeth; Blanco, María B.; Barnes, Ian; Teruel, Mariano A.

    2015-05-01

    Rate coefficients for the gas-phase reactions of O3 molecules with three unsaturated oxygenated compounds have been determined using the relative kinetic technique in an environmental chamber with FTIR detection of the reactants at (298 ± 2) K in 760 Torr total pressure of synthetic air. The following rate coefficients (in units of 10-17 cm3 molecule-1 s-1) were determined: ethyl 3,3-dimethyl acrylate (0.82 ± 0.19), 2-methyl-2-pentenal (0.71 ± 0.16) and 6-methyl-5-hepten-2-one (26 ± 7). The different reactivity of the unsaturated oxygenated compounds toward O3 is discussed in terms of their chemical structure. In addition, a correlation between the reactivity of structurally different unsaturated compounds (alkenes and unsaturated oxygenated VOCs, such as ethers, esters, aldehydes, ketones and alcohols) toward O3 molecules and the HOMO (Highest Occupied Molecular Orbital) of the compounds is presented. Using the kinetic parameters determined in this work, residence times of these unsaturated compounds in the atmosphere with respect to reaction with O3 have been calculated. In urban and rural areas the main sink of 6-methyl-5-hepten-2-one is reaction with O3 molecules with a residence time in the order of few minutes.

  3. Folic Acid

    MedlinePlus

    Folic acid is a B vitamin. It helps the body make healthy new cells. Everyone needs folic acid. For women who may get pregnant, it is really important. Getting enough folic acid before and during pregnancy can prevent major birth ...

  4. Folic Acid

    MedlinePlus

    Folic acid is used to treat or prevent folic acid deficiency. It is a B-complex vitamin needed by ... Folic acid comes in tablets. It usually is taken once a day. Follow the directions on your prescription label ...

  5. Aspartic acid

    MedlinePlus

    ... also called asparaginic acid. Aspartic acid helps every cell in the body work. It plays a role in: Hormone production and release Normal nervous system function Plant sources of aspartic acid include: Legumes such as ...

  6. Production of volatiles in fresh-cut apple: effect of applying alginate coatings containing linoleic acid or isoleucine.

    PubMed

    Maya-Meraz, Irma O; Espino-Díaz, Miguel; Molina-Corral, Francisco J; González-Aguilar, Gustavo A; Jacobo-Cuellar, Juan L; Sepulveda, David R; Olivas, Guadalupe I

    2014-11-01

    One of the main quality parameters in apples is aroma, its main precursors are fatty acids (FA) and amino acids (AA). In this study, alginate edible coatings were used as carriers of linoleic acid or isoleucine to serve as precursors for the production of aroma in cut apples. Apple wedges were immersed in a CaCl2 solution and coated with one of the following formulations: alginate solution (Alg-Ca), Alg-Ca-low-level linoleic acid (0.61 g/Lt), (LFA), Alg-Ca-high-level linoleic acid (2.44 g/L; HFA), Alg-Ca-low-level isoleucine (0.61 g/L; LAA), and Alg-Ca-high-level isoleucine (2.44 g/L; HAA). Apple wedges were stored at 3 °C and 85% relative humidity for 21 d and key volatiles were studied during storage. Addition of precursors, mainly isoleucine, showed to increase the production of some key volatiles on coated fresh-cut apples during storage. The concentration of 2-methyl-1-butanol was 4 times higher from day 12 to day 21 in HAA, while 2-methyl butyl acetate increased from day 12 to day 21 in HAA. After 21 d, HAA-apples presented a 40-fold value of 2-methyl-butyl acetate, compared to Alg-Ca cut apples. Values of hexanal increased during cut apple storage when the coating carried linoleic acid, mainly on HFA, from 3 to 12 d. The ability of apples to metabolize AA and FA depends on the concentration of precursors, but also depends on key enzymes, previous apple storage, among others. Further studies should be done to better clarify the behavior of fresh-cut apples as living tissue to metabolize precursors contained in edible coatings for the production of volatiles. PMID:25296624

  7. Promoter Methylation of the Retinoic Acid Receptor Beta2 (RARβ2) Is Associated with Increased Risk of Breast Cancer: A PRISMA Compliant Meta-Analysis

    PubMed Central

    Shen, Xian-Feng; Wei, Xue-Mei; Yu, Guo-Zheng; Zeng, Xian-Tao

    2015-01-01

    Background Epigenetic studies demonstrate that an association may exist between methylation of the retinoic acid receptor beta2 (RARβ2) gene promoter and breast cancer onset risk, tumor stage, and histological grade, however the results of these studies are not consistent. Hence, we performed this meta-analysis to ascertain a more comprehensive and accurate association. Materials and Methods Relevant studies were retrieved from the PubMed, Embase and Chinese National Knowledge Infrastructure databases up to February 28, 2015. After two independent reviewers screened the studies and extracted the necessary data, meta-analysis was performed using Review Manager 5.2 software. Results Nineteen eligible articles, including 20 studies, were included in our analysis. Compared to non-cancerous controls, the frequency of RARβ2 methylation was 7.27 times higher in patients with breast cancer (odds ratio (OR) = 7.27, 95% confidence interval (CI) = 3.01–17.52). Compared to late-stage RARβ2 methylated patients, the pooled OR of early-stage ones was 0.81 (OR = 0.81, 95% CI = 0.55–1.17). The OR of low-grade RARβ2 methylated patients was 0.96 (OR = 0.96, 95% CI = 0.74–1.25) compared to high-grade RARβ2 methylated patients. Conclusion RARβ2 methylation is significantly increased in breast cancer samples when compared to non-cancerous controls. RARβ2 could serve as a potential epigenetic marker for breast cancer detection and management. PMID:26451736

  8. Dissociation of the effects of MTEP [3-[(2-methyl-1,3-thiazol-4-yl)ethynyl]piperidine] on conditioned reinstatement and reinforcement: comparison between cocaine and a conventional reinforcer.

    PubMed

    Martin-Fardon, R; Baptista, M A S; Dayas, C V; Weiss, F

    2009-06-01

    To advance understanding of the potential of metabotropic glutamate receptor (mGluR) 5 as treatment targets for cocaine addiction, the effects of MTEP [3-[(2-methyl-1,3-thiazol-4-yl) ethynyl]piperidine] (a selective mGluR5 antagonist) on conditioned reinstatement of cocaine seeking were examined. To test whether modification of conditioned reinstatement by MTEP is selective for drug-directed behavior or reflects general actions on motivated behavior, effects of MTEP on reinstatement induced by a stimulus conditioned to palatable conventional reward, sweetened condensed milk (SCM), were also evaluated. Previous data suggest that mGluR manipulations preferentially interfere with conditioned reinstatement compared with cocaine self-administration. Therefore, the effects of MTEP on cocaine self-administration were compared with MTEP's effects on SCM-reinforced behavior using the same cocaine doses and SCM concentrations employed for establishing conditioned reinstatement. Male Wistar rats were trained to associate a discriminative stimulus (S(D)) with response-contingent availability of cocaine or SCM and subjected to reinstatement tests after extinction of cocaine or SCM-reinforced behavior. MTEP (0.3-10 mg/kg i.p.) dose-dependently attenuated the response-reinstating effects of both the cocaine S(D) and SCM S(D). MTEP also decreased cocaine self-administration without a clear graded dose-response profile and did not modify SCM-reinforced responding. The findings implicate mGluR5-regulated glutamate transmission in appetitive behavior controlled by reward-related stimuli but without selectivity for cocaine seeking. However, the data suggest a differential role for mGluR5 in the acute reinforcing effects of cocaine versus conventional reward. These observations identify mGluR5 as potential treatment targets for cocaine relapse prevention, although the profile of action of mGluR5 antagonists remains to be more closely examined for potential anhedonic effects. PMID

  9. A series of dinuclear Dy(iii) complexes bridged by 2-methyl-8-hydroxylquinoline: replacement on the periphery coordinated β-diketonate terminal leads to different single-molecule magnetic properties.

    PubMed

    Zhang, Wan-Ying; Tian, Yong-Mei; Li, Hong-Feng; Chen, Peng; Sun, Wen-Bin; Zhang, Yi-Quan; Yan, Peng-Fei

    2016-03-01

    A series of HMq-bridged dinuclear dysprosium complexes, namely, [Dy(acac)2(CH3OH)]2(μ-HMq)2 (1), [Dy(DBM)2]2(μ-HMq)2(n-C6H14) (2), [Dy(hmac)2]2(μ-HMq)2 (3) and [Dy(hfac)3]2(μ-HMq)2 (4) (HMq = 2-methyl-8-hydroxyquinoline, acac = acetylacetone, DBM = dibenzoylmethane, hmac = hexamethylacetylacetonate and hfac = hexafluoroacetylacetonate), were structurally and magnetically characterized. X-ray crystallographic analyses of the structures reveal that HMq serves as the effective bridge to link two Dy(III) centers by means of the phenoxyl oxygen and nitrogen atoms and the periphery β-diketonate ligands complete the coordination sphere by bidentate oxygen atoms. The different substituents on the β-diketonate terminal lead to different coordination models mostly due to the steric hindrance of these substituents, and the electron-withdrawing or donating effects likely influence the strength of the ligand fields and the Dy(III) ion anisotropy. Measurements of alternating-current (ac) susceptibility on complexes 1-4 reveal that complexes 3 and 4 display significant zero-field single-molecule magnetic (SMM) behavior with barrier energy Ueff/kB = 14.8 K, τ0 = 1.8 × 10(-5) s and Ueff/kB = 9.2 K, τ0 = 1.7 × 10(-5) s, respectively, whereas 1 and 2 exhibit field-induced SMM behavior, and these differences are attributed to the alteration on the periphery β-diketonate ligands. Their distinct slow magnetic relaxation behaviors were related to their different individual Dy(III) ion magnetic anisotropy and intramolecular coupling, which were confirmed by ab initio calculations. PMID:26905041

  10. Synthesis and biological activity of tetralone abscisic acid analogues.

    PubMed

    Nyangulu, James M; Nelson, Ken M; Rose, Patricia A; Gai, Yuanzhu; Loewen, Mary; Lougheed, Brenda; Quail, J Wilson; Cutler, Adrian J; Abrams, Suzanne R

    2006-04-01

    Bicyclic analogues of the plant hormone abscisic acid (ABA) were designed to incorporate the structural elements and functional groups of the parent molecule that are required for biological activity. The resulting tetralone analogues were predicted to have enhanced biological activity in plants, in part because oxidized products would not cyclize to forms corresponding to the inactive catabolite phaseic acid. The tetralone analogues were synthesized in seven steps from 1-tetralone and a range of analogues were accessible through a second route starting with 2-methyl-1-naphthol. Tetralone ABA 8 was found to have greater activity than ABA in two bioassays. The absolute configuration of (+)-8 was established by X-ray crystallography of a RAMP hydrazone derivative. The hydroxymethyl compounds 10 and 11, analogues for studying the roles of 8- and 9-hydroxy ABA 3 and 6, were also synthesized and found to be active. PMID:16557330

  11. Upconversion nanoparticles with a strong acid-resistant capping

    NASA Astrophysics Data System (ADS)

    Recalde, Ileana; Estebanez, Nestor; Francés-Soriano, Laura; Liras, Marta; González-Béjar, María; Pérez-Prieto, Julia

    2016-03-01

    Water-dispersible upconversion nanoparticles (β-NaYF4:Yb3+,Er3+, UCNP) coated with a thin shell of a biocompatible copolymer comprising 2-hydroxyethylmethacrylate (HEMA) and 2-acrylamido-2-methyl-1-propanesulphonsulphonic acid (AMPS), which we will term COP, have been prepared by multidentate grafting. This capping is remarkably resistant to strong acidic conditions as low as pH 2. The additional functionality of the smart UCNP@COP nanosystem has been proved by its association to a well-known photosensitizer (namely, methylene blue, MB). The green-to-red emission ratio of the UC@COP@MB nanohybrid exhibits excellent linear dependence in the 7 to 2 pH range as a consequence of the release of the dye as the pH decreases.Water-dispersible upconversion nanoparticles (β-NaYF4:Yb3+,Er3+, UCNP) coated with a thin shell of a biocompatible copolymer comprising 2-hydroxyethylmethacrylate (HEMA) and 2-acrylamido-2-methyl-1-propanesulphonsulphonic acid (AMPS), which we will term COP, have been prepared by multidentate grafting. This capping is remarkably resistant to strong acidic conditions as low as pH 2. The additional functionality of the smart UCNP@COP nanosystem has been proved by its association to a well-known photosensitizer (namely, methylene blue, MB). The green-to-red emission ratio of the UC@COP@MB nanohybrid exhibits excellent linear dependence in the 7 to 2 pH range as a consequence of the release of the dye as the pH decreases. Electronic supplementary information (ESI) available: Additional spectra and data of HEMA, AMPS, COP, UCNP@oleate, UCNP@COP, and UCNP@COP@MB. See DOI: 10.1039/c5nr06653k

  12. Acid Rain.

    ERIC Educational Resources Information Center

    Openshaw, Peter

    1987-01-01

    Provides some background information on acid deposition. Includes a historical perspective, describes some effects of acid precipitation, and discusses acid rain in the United Kingdom. Contains several experiments that deal with the effects of acid rain on water quality and soil. (TW)

  13. Synthesis, characterization of (3E)-1-(6-chloro-2-methyl-4-phenyl quinolin-3-Yl)-3-aryl prop-2-en-1-ones through IR, NMR, single crystal X-ray diffraction and insights into their electronic structure using DFT calculations

    NASA Astrophysics Data System (ADS)

    Sarveswari, S.; Srikanth, A.; Arul Murugan, N.; Vijayakumar, V.; Jasinski, Jerry P.; Beauchesne, Hanna C.; Jarvis, Ethan E.

    2015-02-01

    3E-1-(6-Chloro-2-methyl-4-phenylquinolin-3-yl)-3-arylprop-2-en-1-ones were synthesized and characterized by FTIR, 1H NMR, 13C NMR, HSQC, DEPT-135. In addition the compound 3E-1-(6-chloro-2-methyl-4-phenylquinolin-3-yl)-3-(2,5-dimethoxyphenyl)prop-2-en-1-one was subjected to the single crystal X-ray diffraction studies. Density functional theory calculations were carried out for this chalcone and its derivatives to investigate into their electronic structure, chemical reactivity, linear and non-linear optical properties. The structure predicted from DFT for chalcone is in good agreement with the structure from XRD measurement.

  14. Effects of the amino-carbonyl reaction of ribose and glycine on the formation of the 2(or 5)-ethyl-5(or 2)-methyl-4-hydroxy-3(2H)-furanone aroma component specific to miso by halo-tolerant yeast.

    PubMed

    Sugawara, Etsuko; Ohata, Motoko; Kanazawa, Toshinari; Kubota, Kikue; Sakurai, Yonekichi

    2007-07-01

    The formation of HEMF[2(or 5)-ethyl-5(or 2)-methyl-4-hydroxy-3(2H)-furanone], the aroma component specific to miso and soy sauce, was promoted by cultivating the halo-tolerant yeast, Zygosaccharomyces rouxii, in a medium including the amino-carbonyl reaction products based on ribose and glycine. The glucose concentration in the medium influenced the HEMF formation by Z. rouxii. PMID:17617718

  15. Structural organization of films based on polyaniline/polysulfonic acid complexes depending on the synthesis method

    SciTech Connect

    Simagina, L. V. Gaynutdinov, R. V.; Stepina, N. D.; Sorokina, K. L.; Morozova, O. V.; Shumakovich, G. P.; Yaropolov, A. I.; Tolstikhina, A. L.

    2010-07-15

    The optical properties and morphology of complexes based on polyaniline (PANI) and poly(2-acrylamido-2-methyl-1-propanesulfonic acid) (PAMPS), depending on their synthesis conditions, have been characterized by UV-visible spectroscopy and atomic force microscopy. The dependence of the electron absorption spectra of PANI/PAMPS complexes and the surface topography of their films on the initiation way of PANI formation (chemical and enzymatic) and the use of promoters of aniline polymerization has been investigated. The aniline polymerization kinetics with and without polymerization promoters has been studied. All PANI/PAMPS complexes are found to have a nanocomposite time-stable structure.

  16. Anticancer potential of pyrrole (1, 2, a) pyrazine 1, 4, dione, hexahydro 3-(2-methyl propyl) (PPDHMP) extracted from a new marine bacterium, Staphylococcus sp. strain MB30.

    PubMed

    Lalitha, P; Veena, V; Vidhyapriya, P; Lakshmi, Pragna; Krishna, R; Sakthivel, N

    2016-05-01

    Marine bacterium, strain MB30 isolated from the deep sea sediment of Bay of Bengal, India, exhibited antimicrobial activity against human pathogenic bacteria. Based on the 16S rRNA sequence homology and subsequent phylogenetic tree analysis, the strain MB30 was identified as Staphylococcus sp. The bioactive metabolite produced by the strain MB30 was purified through silica gel column chromatography and preparative HPLC. Purified metabolite was further characterized by FT-IR, LC-MS and NMR analyses. On the basis of spectroscopic data, the metabolite was identified as pyrrole (1, 2, a) pyrazine 1, 4, dione, hexahydro 3-(2-methyl propyl) (PPDHMP). The PPDHMP exhibited in vitro anticancer potential against lung (A549) and cervical (HeLa) cancer cells in a dose-dependent manner with the IC50 concentration of 19.94 ± 1.23 and 16.73 ± 1.78 μg ml(-1) respectively. The acridine orange (AO)/ethidium bromide (EB) and 4,6-diamidino-2-phenylindole dihydrochloride (DAPI) staining of the IC50 concentration of PPDHMP-treated cancer cells exhibited an array of morphological changes such as nuclear condensation, cell shrinkage and formation of apoptotic bodies. The PPDHMP-treated cancer cells induced the progressive accumulation of fragmented DNA in a time-dependent manner. Based on the flow cytometric analysis, it has become evident that the compound was also effective in arresting the cell cycle at G1 phase. Further, the Western blotting analysis confirmed the down-regulation of cyclin-D1, cyclin dependent kinase (CDK-2), anti-apoptotic Bcl-2 family proteins (Bcl-2 and Bcl-xL), activation of caspase-9 and 3 with the cleavage of PARP. The PPDHMP-treated cancer cells also showed the inhibition of migration and invasive capacity of cancer cells. In the present investigation, for the first time, we have reported the extraction, purification and characterization of an anticancer metabolite, PPDHMP from a new marine bacterium, Staphylococcus sp. strain MB30. PMID:26852140

  17. Experimental and Quantum Studies on Adsorption and Corrosion Inhibition Effect of Imidazole Derivatives on N80 Steel in Hydrochloric Acid

    NASA Astrophysics Data System (ADS)

    Yadav, M.; Kumar, Sumit; Sharma, Dipti; Yadav, P. N.

    2013-12-01

    The inhibition effect of synthesized N‧-(phenylmethylidene)-2-(2-methyl-1H-benzimidazol-1-yl)acetohydrazides, N‧-(4-methylphenylmethylidene)-2-(2-methyl-1H-benzimidazol-1-yl)acetohydrazides, and N‧-(4-methoxyphenylmethylidene)-2-(2-methyl-1H-benzimidazol-1-yl)acetohydrazides on the corrosion behaviour of N80 steel in 15% hydrochloric acid solution was investigated using weight loss, potentiostatic polarization and electrochemical impedance spectroscopy methods. The inhibition efficiency increased as the concentration of the inhibitors was increased. The effect of temperature on corrosion inhibition was investigated by weight loss method and thermodynamic parameters were calculated. Potentiodynamic polarization measurements show that all the three studied inhibitors act as mixed inhibitor. The adsorption of inhibitors on N80 steel surface obeys Langmuir adsorption isotherm. The structure of inhibitors was optimized using semiemperical AM1 method. Theoretical parameters such as the highest occupied molecular orbital (EHOMO), lowest unoccupied molecular orbital (ELUMO) energy levels, energy gap (ΔE = ELUMO - EHOMO), dipole moment (μ), global hardness (γ), softness (σ), binding energy, molecular surface area and the fraction of electrons transferred (ΔN) were calculated and the adsorption mechanism was discussed. Scanning electron microscopy was used to characterize the surface marphology of the N80 steel.

  18. Enthalpies of Mixing for Binary Liquid Mixtures of Monocarbonic Acids and Alcohols

    NASA Astrophysics Data System (ADS)

    Haase, R.; Lorenz, R.

    1985-09-01

    We present the results of calorimetric measurements of the molar enthalpy of mixing (molar excess enthalpy) H¯E as a function of temperature and composition (described by the mole fraction x of the alcohol) for 18 binary liquid systems consisting of an aliphatic monocarbonic acid (formic, acetic, propionic, butyric, valeric acids) and an aliphatic alcohol (methanol, ethanol, 1-propanol. 2-propanol, 1-butanol, 2-methyl-2-propanol). The experiments cover temperatures between 298.15 K and 318.15 K and the whole range of compositions (usually nearly 40 compositions at each temperature). There is a great variety of behaviour as far as the function H¯E(x) for T= const is concerned. Many systems show endothermic mixing ( H¯E > 0), other systems exothermic mixing (H¯E < 0), again other systems partly endothermic, partly exothermic behaviour. There is one case (acetic acid + 2-methyl-2-propanol) where H¯E(x) changes its sign twice and the molar excess heat capacity exhibits unusually large negative values.

  19. Structure of eight molecular salts assembled from noncovalent bonding between carboxylic acids, imidazole, and benzimidazole

    NASA Astrophysics Data System (ADS)

    Jin, Shouwen; Zhang, Huan; Liu, Hui; Wen, Xianhong; Li, Minghui; Wang, Daqi

    2015-09-01

    Eight organic salts of imidazole/benzimidazole have been prepared with carboxylic acids as 2-methyl-2-phenoxypropanoic acid, α-ketoglutaric acid, 5-nitrosalicylic acid, isophthalic acid, 4-nitro-phthalic acid, and 3,5-dinitrosalicylic acid. The eight crystalline forms reported are proton-transfer compounds of which the crystals and compounds were characterized by X-ray diffraction analysis, IR, mp, and elemental analysis. These structures adopted hetero supramolecular synthons, with the most common R22(7) motif observed at salts 2, 3, 5, 6 and 8. Analysis of the crystal packing of 1-8 suggests that there are extensive strong Nsbnd H⋯O, and Osbnd H⋯O hydrogen bonds (charge assisted or neutral) between acid and imidazolyl components in all of the salts. Except the classical hydrogen bonding interactions, the secondary propagating interactions also play important roles in structure extension. This variety, coupled with the varying geometries and number of acidic groups of the acids utilized, has led to the creation of eight supramolecular arrays with 1D-3D structure. The role of weak and strong noncovalent interactions in the crystal packing is analyzed. The results presented herein indicate that the strength and directionality of the Nsbnd H⋯O, and Osbnd H⋯O hydrogen bonds between acids and imidazole/benzimidazole are sufficient to bring about the formation of organic salts.

  20. Amino acids

    MedlinePlus

    ... this page: //medlineplus.gov/ency/article/002222.htm Amino acids To use the sharing features on this page, please enable JavaScript. Amino acids are organic compounds that combine to form proteins . ...

  1. Mefenamic Acid

    MedlinePlus

    Mefenamic acid is used to relieve mild to moderate pain, including menstrual pain (pain that happens before or during a menstrual period). Mefenamic acid is in a class of medications called NSAIDs. ...

  2. Aminocaproic Acid

    MedlinePlus

    Aminocaproic acid is used to control bleeding that occurs when blood clots are broken down too quickly. This type ... the baby is ready to be born). Aminocaproic acid is also used to control bleeding in the ...

  3. Ascorbic Acid

    MedlinePlus

    Ascorbic acid is used to prevent and treat scurvy, a disease caused by a lack of vitamin C in ... Ascorbic acid comes in extended-release (long-acting) capsules and tablets, lozenges, syrup, chewable tablets, and liquid drops to ...

  4. Acid mucopolysaccharides

    MedlinePlus

    ... this page: //medlineplus.gov/ency/article/003368.htm Acid mucopolysaccharides To use the sharing features on this page, please enable JavaScript. Acid mucopolysaccharides is a test that measures the amount ...

  5. Ethacrynic Acid

    MedlinePlus

    Ethacrynic acid, a 'water pill,' is used to treat swelling and fluid retention caused by various medical problems. It ... Ethacrynic acid comes as a tablet to take by mouth. It is usually taken once or twice a day ...

  6. Differential effects of a short-term high-fat diet in an animal model of depression in rats treated with the 5-HT3 receptor antagonist, ondansetron, the 5-HT3 receptor agonist, 2-methyl-5-HT, and the SSRI, fluoxetine.

    PubMed

    Sumaya, Isabel C; Bailey, Dee; Catlett, Susan L

    2016-05-01

    Investigation into the effects of a high-fat diet on depression in the context of 5-HT3 receptor function is important given 5-HT3 antagonism may represent a novel candidate for drug discovery. To more fully understand the relationship between the 5-HT3 receptor system, depression, and high-fat intake, our main interest was to study the short-term effects of a high-fat diet on the 5-HT3 receptor antagonist, ondansetron, and the 5-HT3 receptor agonist, 2-methyl-5-HT, as well as the SSRI, fluoxetine, in an animal model of depression. Male Sprague Dawley rats were fed either a standard diet (11% fat) or a high-fat diet (32.5% fat) for seven days then treated with either fluoxetine (10mg/kg, ip), ondansetron (1mg/kg, ip), 2-methyl-5-HT (3mg/kg, ip), fluoxetine+ondansetron or, 2-methyl-5-HT+ondansetron prior to the Forced Swim Test. In the standard diet group, treatment with the 5HT3 receptor agonist, 2-methyl-5-HT, served to significantly decrease time of immobility as compared to controls thus showing anti-depressive-like effects. Treatment with the 5-HT3 receptor antagonist, ondansetron, served to enhance the anti-depressive like effects of the SSRI, fluoxetine, as treatment with both the SSRI and 5-HT3 receptor antagonist dramatically decreased immobility. Importantly, in the high-fat diet groups, a week of high-fat intake served to: 1) counteract the anti-depressive-like effect of the SSRI, fluoxetine, 2) reverse the anti-depressive-like effect of the 5HT3 receptor agonist, 2-methyl-5-HT and 3) provide protection against the depressive-like effects induced by the Forced Swim Test as rats fed a high-fat diet displayed the lowest amounts of immobility. In the aggregate, these data suggest that both SSRIs and the 5HT3 receptor system are affected by short-term high-fat intake and that a short-term high-fat diet protects against depressive-like effects in an animal model of depression. PMID:26979154

  7. Valproic Acid

    MedlinePlus

    Valproic acid is used alone or with other medications to treat certain types of seizures. Valproic acid is also used to treat mania (episodes of ... to relieve headaches that have already begun. Valproic acid is in a class of medications called anticonvulsants. ...

  8. Fatty acids - trans fatty acids

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The data supporting a negative effect of dietary trans fatty acids on cardiovascular disease risk is consistent. The primary dietary sources of trans fatty acids include partially hydrogenated fat and rudiment fat. The adverse effect of trans fatty acids on plasma lipoprotein profiles is consisten...

  9. Allosteric inhibition of glycogen phosphorylase a by the potential antidiabetic drug 3-isopropyl 4-(2-chlorophenyl)-1,4-dihydro-1-ethyl-2-methyl-pyridine-3,5,6-tricarbo xylate.

    PubMed Central

    Oikonomakos, N. G.; Tsitsanou, K. E.; Zographos, S. E.; Skamnaki, V. T.; Goldmann, S.; Bischoff, H.

    1999-01-01

    The effect of the potential antidiabetic drug (-)(S)-3-isopropyl 4-(2-chlorophenyl)-1,4-dihydro-1-ethyl-2-methyl-pyridine-3,5,6-tricarbox ylate (W1807) on the catalytic and structural properties of glycogen phosphorylase a has been studied. Glycogen phosphorylase (GP) is an allosteric enzyme whose activity is primarily controlled by reversible phosphorylation of Ser14 of the dephosphorylated enzyme (GPb, less active, predominantly T-state) to form the phosphorylated enzyme (GPa, more active, predominantly R-state). Upon conversion of GPb to GPa, the N-terminal tail (residues 5-22), which carries the Ser14(P), changes its conformation into a distorted 3(10) helix and its contacts from intrasubunit to intersubunit. This alteration causes a series of tertiary and quaternary conformational changes that lead to activation of the enzyme through opening access to the catalytic site. As part of a screening process to identify compounds that might contribute to the regulation of glycogen metabolism in the noninsulin dependent diabetes diseased state, W1807 has been found as the most potent inhibitor of GPb (Ki = 1.6 nM) that binds at the allosteric site of T-state GPb and produces further conformational changes, characteristic of a T'-like state. Kinetics show W1807 is a potent competitive inhibitor of GPa (-AMP) (Ki = 10.8 nM) and of GPa (+1 mM AMP) (Ki = 19.4 microM) with respect to glucose 1-phosphate and acts in synergism with glucose. To elucidate the structural features that contribute to the binding, the structures of GPa in the T-state conformation in complex with glucose and in complex with both glucose and W1807 have been determined at 100 K to 2.0 A and 2.1 A resolution, and refined to crystallographic R-values of 0.179 (R(free) = 0.230) and 0.189 (R(free) = 0.263), respectively. W1807 binds tightly at the allosteric site and induces substantial conformational changes both in the vicinity of the allosteric site and the subunit interface. A disordering of the N

  10. Allosteric inhibition of glycogen phosphorylase a by the potential antidiabetic drug 3-isopropyl 4-(2-chlorophenyl)-1,4-dihydro-1-ethyl-2-methyl-pyridine-3,5,6-tricarbo xylate.

    PubMed

    Oikonomakos, N G; Tsitsanou, K E; Zographos, S E; Skamnaki, V T; Goldmann, S; Bischoff, H

    1999-10-01

    The effect of the potential antidiabetic drug (-)(S)-3-isopropyl 4-(2-chlorophenyl)-1,4-dihydro-1-ethyl-2-methyl-pyridine-3,5,6-tricarbox ylate (W1807) on the catalytic and structural properties of glycogen phosphorylase a has been studied. Glycogen phosphorylase (GP) is an allosteric enzyme whose activity is primarily controlled by reversible phosphorylation of Ser14 of the dephosphorylated enzyme (GPb, less active, predominantly T-state) to form the phosphorylated enzyme (GPa, more active, predominantly R-state). Upon conversion of GPb to GPa, the N-terminal tail (residues 5-22), which carries the Ser14(P), changes its conformation into a distorted 3(10) helix and its contacts from intrasubunit to intersubunit. This alteration causes a series of tertiary and quaternary conformational changes that lead to activation of the enzyme through opening access to the catalytic site. As part of a screening process to identify compounds that might contribute to the regulation of glycogen metabolism in the noninsulin dependent diabetes diseased state, W1807 has been found as the most potent inhibitor of GPb (Ki = 1.6 nM) that binds at the allosteric site of T-state GPb and produces further conformational changes, characteristic of a T'-like state. Kinetics show W1807 is a potent competitive inhibitor of GPa (-AMP) (Ki = 10.8 nM) and of GPa (+1 mM AMP) (Ki = 19.4 microM) with respect to glucose 1-phosphate and acts in synergism with glucose. To elucidate the structural features that contribute to the binding, the structures of GPa in the T-state conformation in complex with glucose and in complex with both glucose and W1807 have been determined at 100 K to 2.0 A and 2.1 A resolution, and refined to crystallographic R-values of 0.179 (R(free) = 0.230) and 0.189 (R(free) = 0.263), respectively. W1807 binds tightly at the allosteric site and induces substantial conformational changes both in the vicinity of the allosteric site and the subunit interface. A disordering of the N

  11. Solubility of acid gases in a mixed solvent

    SciTech Connect

    MacGregor, R.J.; Mather, A.E.

    1987-01-01

    The solubility of hydrogen sulphide and carbon dioxide and their mixtures has been measured at 40/sup 0/ and 100/sup 0/C in a mixed solvent consisting of 20.9 wt% (2.0 M) MDEA (methyldiethanolamine), 30.5 wt% sulfolane, and 48.6 wt% water. The results have been compared with those for aqueous 2.0 M MDEA and an analogous mixed solvent, containing AMP (2-amino-2-methyl-1-propanol), which are available in the literature. At solution loadings less than 1 mol acid gas/mol MDEA, the solubility of the acid gas was lower in the mixed solvent that in the corresponding aqueous MDEA solvent; at solution loadings greater than 1 mol acid gas/mol MDEA, the reverse was true. At all loadings and at both temperatures studied, the mixed MDEA solvent absorbed equal or lesser quantities of acid gas than the comparable mixed AMP solvent. However, the shapes of the solubility curves show that the mixed MDEA solvent would be a better choice for certain industrial applications. These data were used to modify the solubility model of Deshmukh and Mather to account for the mixed solvent effects on the system thermodynamics. Results show that the model is useful as a first approximation in predicting acid gas solubilities; agreement with experiment was generally found to be within +-15%.

  12. Nonenzymatic oligomerization reactions on templates containing inosinic acid or diaminopurine nucleotide residues

    NASA Technical Reports Server (NTRS)

    Kozlov, I. A.; Orgel, L. E.; Bada, J. L. (Principal Investigator)

    1999-01-01

    The template-directed oligomerization of nucleoside-5'-phosphoro-2-methyl imidazolides on standard oligonucleotide templates has been studied extensively. Here, we describe experiments with templates in which inosinic acid (I) is substituted for guanylic acid, or 2,6-diaminopurine nucleotide (D) for adenylic acid. We find that the substitution of I for G in a template is strongly inhibitory and prevents any incorporation of C into internal positions in the oligomeric products of the reaction. The substitution of D for A, on the contrary, leads to increased incorporation of U into the products. We found no evidence for the template-directed facilitation of oligomerization of A or I through A-I base pairing. The significance of these results for prebiotic chemistry is discussed.

  13. Zirconium-titanium phosphate acid catalysts synthesized by sol gel techniques

    SciTech Connect

    Jackson, N.B.; Thoma, S.G.; Kohler, S.; Nenoff, T.M.

    1998-03-01

    Recently a large effort has been put into identifying solid acid materials, particularly sulfated zirconia and other sulfated metal oxides, that can be used to replace environmentally hazardous liquid acids in industrial processes. The authors are studying a group of mixed metal phosphates, some of which have also been sulfated, for their catalytic and morphological characteristics. Zirconium and titanium are the metals used in this study and the catalysts are synthesized from alkoxide starting materials with H{sub 3}PO{sub 4}, H{sub 2}O, and sometimes H{sub 2}SO{sub 4} as gelling agents. The measurement of acidity was achieved by using the isomerization of 2-methyl-2-pentene as a model reaction. The phosphate stabilized the mixed metal sulfates, preventing them from calcining to oxides boosting their initial catalytic activity. The addition of sulfate prevented the formation of the catalytically inactive mixed metal pyrophosphates when calcined at high temperatures (> 773 K).

  14. Fatty acid constituents of Peganum harmala plant using Gas Chromatography–Mass Spectroscopy

    PubMed Central

    Moussa, Tarek A.A.; Almaghrabi, Omar A.

    2015-01-01

    Fatty acid contents of the Peganum harmala plant as a result of hexane extraction were analyzed using GC–MS. The saturated fatty acid composition of the harmal plant was tetradecanoic, pentadecanoic, tridecanoic, hexadecanoic, heptadecanoic and octadecanoic acids, while the saturated fatty acid derivatives were 12-methyl tetradecanoic, 5,9,13-trimethyl tetradecanoic and 2-methyl octadecanoic acids. The most abundant fatty acid was hexadecanoic with concentration 48.13% followed by octadecanoic with concentration 13.80%. There are four unsaturated fatty acids called (E)-9-dodecenoic, (Z)-9-hexadecenoic, (Z,Z)-9,12-octadecadienoic and (Z,Z,Z)-9,12,15-octadecatrienoic. The most abundant unsaturated fatty acid was (Z,Z,Z)-9,12,15-octadecatrienoic with concentration 14.79% followed by (Z,Z)-9,12-octadecadienoic with concentration 10.61%. Also, there are eight non-fatty acid compounds 1-octadecene, 6,10,14-trimethyl-2-pentadecanone, (E)-15-heptadecenal, oxacyclohexadecan-2 one, 1,2,2,6,8-pentamethyl-7-oxabicyclo[4.3.1]dec-8-en-10-one, hexadecane-1,2-diol, n-heneicosane and eicosan-3-ol. PMID:27081366

  15. Fatty acid constituents of Peganum harmala plant using Gas Chromatography-Mass Spectroscopy.

    PubMed

    Moussa, Tarek A A; Almaghrabi, Omar A

    2016-05-01

    Fatty acid contents of the Peganum harmala plant as a result of hexane extraction were analyzed using GC-MS. The saturated fatty acid composition of the harmal plant was tetradecanoic, pentadecanoic, tridecanoic, hexadecanoic, heptadecanoic and octadecanoic acids, while the saturated fatty acid derivatives were 12-methyl tetradecanoic, 5,9,13-trimethyl tetradecanoic and 2-methyl octadecanoic acids. The most abundant fatty acid was hexadecanoic with concentration 48.13% followed by octadecanoic with concentration 13.80%. There are four unsaturated fatty acids called (E)-9-dodecenoic, (Z)-9-hexadecenoic, (Z,Z)-9,12-octadecadienoic and (Z,Z,Z)-9,12,15-octadecatrienoic. The most abundant unsaturated fatty acid was (Z,Z,Z)-9,12,15-octadecatrienoic with concentration 14.79% followed by (Z,Z)-9,12-octadecadienoic with concentration 10.61%. Also, there are eight non-fatty acid compounds 1-octadecene, 6,10,14-trimethyl-2-pentadecanone, (E)-15-heptadecenal, oxacyclohexadecan-2 one, 1,2,2,6,8-pentamethyl-7-oxabicyclo[4.3.1]dec-8-en-10-one, hexadecane-1,2-diol, n-heneicosane and eicosan-3-ol. PMID:27081366

  16. Acid Deposition

    EPA Science Inventory

    This indicator presents acid deposition trends in the contiguous U.S. from 1989 to 2007. Data are broken down by wet and dry deposition and deposition of nitrogen and sulfur compounds. Acid deposition is particularly damaging to lakes, streams, and forests and the plants and a...

  17. Acid rain

    SciTech Connect

    White, J.C. )

    1988-01-01

    This book presents the proceedings of the third annual conference sponsored by the Acid Rain Information Clearinghouse (ARIC). Topics covered include: Legal aspects of the source-receptor relationship: an energy perspective; Scientific uncertainty, agency inaction, and the courts; and Acid rain: the emerging legal framework.

  18. Acid rain

    SciTech Connect

    Elsworth, S.

    1985-01-01

    This book was written in a concise and readable style for the lay public. It's purpose was to make the public aware of the damage caused by acid rain and to mobilize public opinion to favor the elimination of the causes of acid rain.

  19. Acid rain

    SciTech Connect

    Sweet, W.

    1980-06-20

    Acid precipitation includes not only rain but also acidified snow, hail and frost, as well as sulfur and nitrogen dust. The principal source of acid precipitation is pollution emitted by power plants and smelters. Sulfur and nitrogen compounds contained in the emissions combine with moisture to form droplets with a high acid content - sometimes as acidic as vinegar. When sufficiently concentrated, these acids can kill fish and damage material structures. Under certain circumstances they may reduce crop and forest yields and cause or aggravate respiratory diseases in humans. During the summer, especially, pollutants tend to collect over the Great Lakes in high pressure systems. Since winds typically are westerly and rotate clockwise around high pressure systems, the pollutants gradually are dispersed throughout the eastern part of the continent.

  20. Asparagusic acid.

    PubMed

    Mitchell, Stephen C; Waring, Rosemary H

    2014-01-01

    Asparagusic acid (1,2-dithiolane-4-carboxylic acid) is a simple sulphur-containing 5-membered heterocyclic compound that appears unique to asparagus, though other dithiolane derivatives have been identified in non-food species. This molecule, apparently innocuous toxicologically to man, is the most probable culprit responsible for the curious excretion of odorous urine following asparagus ingestion. The presence of the two adjacent sulphur atoms leads to an enhanced chemical reactivity, endowing it with biological properties including the ability to substitute potentially for α-lipoic acid in α-keto-acid oxidation systems. This brief review collects the scattered data available in the literature concerning asparagusic acid and highlights its properties, intermediary metabolism and exploratory applications. PMID:24099657

  1. Isolation and kinetic properties of acetohydroxy acid isomeroreductase from spinach (Spinacia oleracea) chloroplasts overexpressed in Escherichia coli.

    PubMed

    Dumas, R; Job, D; Ortholand, J Y; Emeric, G; Greiner, A; Douce, R

    1992-12-15

    Acetohydroxy acid isomeroreductase catalyses a two-step reaction, an alkyl migration and a NADPH-dependent reduction, in the assembly of the carbon skeletons of branched-chain amino acids. Detailed investigations of acetohydroxy acid isomeroreductase aimed at elucidating the biosynthetic pathway of branched-chain amino acids and at designing new inhibitors of the enzyme having herbicidal potency have so far been conducted with the enzymes isolated from bacteria. To gain more information on a plant system, the gene encoding the mature acetohydroxy acid isomeroreductase from spinach (Spinacia oleracea) leaf chloroplasts has been used to transform Escherichia coli cells and to overexpress the enzyme. A rapid protocol is described that allows the preparation of large quantities of pure spinach chloroplast acetohydroxy acid isomeroreductase. Kinetic and structural properties of the plant enzyme expressed in Escherichia coli are compared with those reported in our previous studies on the native enzymes purified from spinach chloroplasts and with those reported for the corresponding enzymes isolated from Escherichia coli and Salmonella typhimurium. Both the plant and the bacterial enzymes obey an ordered mechanism in which NADPH binds first, followed by substrate (either 2-acetolactate or 2-aceto-2-hydroxybutyrate). Inhibition studies employing an inactive substrate analogue, 2-hydroxy-2-methyl-3-oxopentanoate, showed, however, that the binding of 2-hydroxy-2-methyl-3-oxopentanoate and NADPH occurs randomly, suggestive of some flexibility of the plant enzyme active site. The observed preference of the enzyme for 2-aceto-2-hydroxybutyrate over 2-acetolactate is discussed with regard to the contribution of acetohydroxy acid isomeroreductase activity in the partitioning between isoleucine and valine biosyntheses. Moreover, the kinetic properties of the chloroplast enzyme support the notion that biosynthesis of branched-chain amino acids in plants is controlled by light. As

  2. [Gastric Acid].

    PubMed

    Ruíz Chávez, R

    1996-01-01

    Gastric acid, a product of parietal cells secretion, full fills multiple biological roles which are absolutely necessary to keep corporal homeostasis. The production of the acid depends upon an effector cellular process represented in the first step by histamine, acetilcholine and gastrin, first messengers of the process. These interact with specific receptors than in sequence activate second messengers -cAMP and the calcium-calmodulin system- which afterwards activate a kinase. An specific protein is then phosphorilated by this enzyme, being the crucial factor that starts the production of acid. Finally, a proton bomb, extrudes the acid towards the gastric lumen. The secretion process mentioned above, is progressive lyactivated in three steps, two of which are stimulators -cephalic and gastric phases- and the other one inhibitor or intestinal phase. These stages are started by mental and neurological phenomena -thought, sight, smell or memory-; by food, drugs or other ingested substances; and by products of digestion. Changes in regulation of acid secretion, in the structure of gastro-duodenal mucosal barrier by a wide spectrum of factors and agents including food, drugs and H. pylori, are the basis of acid-peptic disease, entity in which gastric acid plays a fundamental role. From the therapeutic point of view, so at the theoretical as at the practical levels, t is possible to interfere with the secretion of acid by neutralization of some of the steps of the effector cellular process. An adequate knowledge of the basics related to gastric acid, allows to create strategies for the clinical handling of associated pathology, specifically in relation to peptic acid disease in all of the known clinical forms. PMID:12165790

  3. Acid fog

    SciTech Connect

    Hileman, B.

    1983-03-01

    Fog in areas of southern California previously thought to be pollution-free has been shown to have a pH as low as 1.69. It has been found to be most acidic after smoggy days, suggesting that it forms on the aerosol associated with the previously exiting smog. Studies on Whiteface Mountain in the Adirondacks show that fog water is often 10 times as acidic as rainwater. As a result of their studies, California plans to spend $4 million on acid deposition research in the coming year. (JMT)

  4. Folic acid

    MedlinePlus

    ... in the blood vessel to keep it open. Bipolar disorder. Taking folic acid does not appear to improve the antidepressant effects of lithium in people with bipolar disorder. However, taking folate with the medication valproate improves ...

  5. Mefenamic Acid

    MedlinePlus

    ... as mefenamic acid may cause ulcers, bleeding, or holes in the stomach or intestine. These problems may ... like coffee grounds, blood in the stool, or black and tarry stools.Keep all appointments with your ...

  6. ACID RAIN

    EPA Science Inventory

    Acid precipitation has become one of the major environmental problems of this decade. It is a challenge to scientists throughout the world. Researchers from such diverse disciplines as plant pathology, soil science, bacteriology, meteorology and engineering are investigating diff...

  7. Acid Precipitation

    ERIC Educational Resources Information Center

    Likens, Gene E.

    1976-01-01

    Discusses the fact that the acidity of rain and snow falling on parts of the U.S. and Europe has been rising. The reasons are still not entirely clear and the consequences have yet to be well evaluated. (MLH)

  8. Carnosic acid.

    PubMed

    Birtić, Simona; Dussort, Pierre; Pierre, François-Xavier; Bily, Antoine C; Roller, Marc

    2015-07-01

    Carnosic acid (salvin), which possesses antioxidative and antimicrobial properties, is increasingly exploited within the food, nutritional health and cosmetics industries. Since its first extraction from a Salvia species (∼70 years ago) and its identification (∼50 years ago), numerous articles and patents (∼400) have been published on specific food and medicinal applications of Rosmarinus and Salvia plant extracts abundant in carnosic acid. In contrast, relevant biochemical, physiological or molecular studies in planta have remained rare. In this overview, recent advances in understanding of carnosic acid distribution, biosynthesis, accumulation and role in planta, and its applications are summarised. We also discuss the deficiencies in our understanding of the relevant biochemical processes, and suggest the molecular targets of carnosic acid. Finally, future perspectives and studies related to its potential roles are highlighted. PMID:25639596

  9. Aminocaproic Acid

    MedlinePlus

    Amicar® Oral Solution ... Aminocaproic acid comes as a tablet and a solution (liquid) to take by mouth. It is usually ... it at room temperature and away from excess heat and moisture (not in the bathroom). Throw away ...

  10. Tranexamic Acid

    MedlinePlus

    ... is used to treat heavy bleeding during the menstrual cycle (monthly periods) in women. Tranexamic acid is in ... tablets for more than 5 days in a menstrual cycle or take more than 6 tablets in a ...

  11. Acidic precipitation

    SciTech Connect

    Martin, H.C.

    1987-01-01

    At the International Symposium on Acidic Precipitation, over 400 papers were presented, and nearly 200 of them are included here. They provide an overview of the present state of the art of acid rain research. The Conference focused on atmospheric science (monitoring, source-receptor relationships), aquatic effects (marine eutrophication, lake acidification, impacts on plant and fish populations), and terrestrial effects (forest decline, soil acidification, etc.).

  12. Characterization of a Cross-Linked Protein-Nucleic Acid Substrate Radical in the Reaction Catalyzed by RlmN

    SciTech Connect

    Silakov, Alexey; Grove, Tyler L.; Radle, Matthew I.; Bauerle, Matthew R.; Green, Michael T.; Rosenzweig, Amy C.; Boal, Amie K.; Booker, Squire J.

    2014-08-14

    RlmN and Cfr are methyltransferases/methylsynthases that belong to the radical S-adenosylmethionine superfamily of enzymes. RlmN catalyzes C2 methylation of adenosine 2503 (A2503) of 23S rRNA, while Cfr catalyzes C8 methylation of the exact same nucleotide, and will subsequently catalyze C2 methylation if the site is unmethylated. A key feature of the unusual mechanisms of catalysis proposed for these enzymes is the attack of a methylene radical, derived from a methylcysteine residue, onto the carbon center undergoing methylation to generate a paramagnetic protein–nucleic acid cross-linked species. This species has been thoroughly characterized during Cfr-dependent C8 methylation, but does not accumulate to detectible levels in RlmN-dependent C2 methylation. Herein, we show that inactive C118S/A variants of RlmN accumulate a substrate-derived paramagnetic species. Characterization of this species by electron paramagnetic resonance spectroscopy in concert with strategic isotopic labeling shows that the radical is delocalized throughout the adenine ring of A2503, although predominant spin density is on N1 and N3. Moreover, 13C hyperfine interactions between the radical and the methylene carbon of the formerly [methyl-13C]Cys355 residue show that the radical species exists in a covalent cross-link between the protein and the nucleic acid substrate. X-ray structures of RlmN C118A show that, in the presence of SAM, the substitution does not alter the active site structure compared to that of the wild-type enzyme. Together, these findings have new mechanistic implications for the role(s) of C118 and its counterpart in Cfr (C105) in catalysis, and suggest involvement of the residue in resolution of the cross-linked species via a radical mediated process

  13. Characterization of a Cross-Linked Protein–Nucleic Acid Substrate Radical in the Reaction Catalyzed by RlmN

    PubMed Central

    2015-01-01

    RlmN and Cfr are methyltransferases/methylsynthases that belong to the radical S-adenosylmethionine superfamily of enzymes. RlmN catalyzes C2 methylation of adenosine 2503 (A2503) of 23S rRNA, while Cfr catalyzes C8 methylation of the exact same nucleotide, and will subsequently catalyze C2 methylation if the site is unmethylated. A key feature of the unusual mechanisms of catalysis proposed for these enzymes is the attack of a methylene radical, derived from a methylcysteine residue, onto the carbon center undergoing methylation to generate a paramagnetic protein–nucleic acid cross-linked species. This species has been thoroughly characterized during Cfr-dependent C8 methylation, but does not accumulate to detectible levels in RlmN-dependent C2 methylation. Herein, we show that inactive C118S/A variants of RlmN accumulate a substrate-derived paramagnetic species. Characterization of this species by electron paramagnetic resonance spectroscopy in concert with strategic isotopic labeling shows that the radical is delocalized throughout the adenine ring of A2503, although predominant spin density is on N1 and N3. Moreover, 13C hyperfine interactions between the radical and the methylene carbon of the formerly [methyl-13C]Cys355 residue show that the radical species exists in a covalent cross-link between the protein and the nucleic acid substrate. X-ray structures of RlmN C118A show that, in the presence of SAM, the substitution does not alter the active site structure compared to that of the wild-type enzyme. Together, these findings have new mechanistic implications for the role(s) of C118 and its counterpart in Cfr (C105) in catalysis, and suggest involvement of the residue in resolution of the cross-linked species via a radical mediated process. PMID:24806349

  14. Genetic and epigenetic transgenerational implications related to omega-3 fatty acids. Part I: maternal FADS2 genotype and DNA methylation correlate with polyunsaturated fatty acid status in toddlers: an exploratory analysis.

    PubMed

    Lupu, Daniel S; Cheatham, Carol L; Corbin, Karen D; Niculescu, Mihai D

    2015-11-01

    Polyunsaturated fatty acid metabolism in toddlers is regulated by a complex network of interacting factors. The contribution of maternal genetic and epigenetic makeup to this milieu is not well understood. In a cohort of mothers and toddlers 16 months of age (n = 65 mother-child pairs), we investigated the association between maternal genetic and epigenetic fatty acid desaturase 2 (FADS2) profiles and toddlers' n-6 and n-3 fatty acid metabolism. FADS2 rs174575 variation and DNA methylation status were interrogated in mothers and toddlers, as well as food intake and plasma fatty acid concentrations in toddlers. A multivariate fit model indicated that maternal rs174575 genotype, combined with DNA methylation, can predict α-linolenic acid plasma concentration in all toddlers and arachidonic acid concentrations in boys. Arachidonic acid intake was predictive for its plasma concentration in girls, whereas intake of 3 major n-3 species (eicosapentaenoic, docosapentaenoic, and docosahexaenoic acids) were predictive for their plasma concentrations in boys. FADS2 genotype and DNA methylation in toddlers were not related to plasma concentrations or food intakes, except for CpG8 methylation. Maternal FADS2 methylation was a predictor for the boys' α-linolenic acid intakes. This exploratory study suggests that maternal FADS2 genetic and epigenetic status could be related to toddlers' polyunsaturated fatty acid metabolism. PMID:26439440

  15. E.S.R. of spin-trapped radicals in gamma-irradiated polycrystalline amino acids. Chromatographic separation of radicals.

    PubMed

    Makino, K; Riesz, P

    1982-06-01

    The free radicals produced by gamma-radiolysis of polycrystalline amino acids (L-valine, L-leucine, L-isoleucine and L-proline) at room temperature in the absence of air were investigated by spin trapping with 2-methyl-2-nitrosopropane (MNP). The spin adducts produced by dissolving the irradiated solids in aqueous MNP solutions were separated by high-performance liquid chromatography and then identified by e.s.r. Deamination (ring-opening reaction for L-proline) was observed for all amino acid. For L-valine and L-leucine, H-abstraction from the tertiary carbon in the side chains occurred. For isoleucine, H-abstractions from the alpha-carbon of the amino acid and from a non-terminal carbon in the side chain were found. PMID:6288602

  16. ATR-FTIR characterization of transport properties of benzoic acid ion-pairs in silicone membranes.

    PubMed

    Tantishaiyakul, Vimon; Phadoongsombut, Narubodee; Wongpuwarak, Wibul; Thungtiwachgul, Jatupit; Faroongsarng, Damrongsak; Wiwattanawongsa, Kamonthip; Rojanasakul, Yon

    2004-09-28

    A novel technique based on Attenuated Total Reflectance Fourier Transform Infrared (ATR-FTIR) spectroscopy was used to study the transport of benzoic acid ion-pairs/salts in silicone membranes. The benzoic acid ion-pairs were prepared using various counter-ions with different degrees of lipophilicity, e.g. triethylamine (TA), diethylamine (DE), tert-butylamine (t-BA), 2-amino-2-methyl-propanol (AMP), and 2-amino-2-methyl-propanediol (AMPD). Silicone membrane, treated or untreated with propylene glycol (PG), was placed on the surface of a ZnSe crystal and the transport solution was applied to the upper surface of the membrane. A mathematical model, based on Fick's second law describing the build up of permeant concentration at the membrane/crystal interface with time was applied to determine diffusion coefficients. Absorption due to the acid (1700 cm(-1)) or benzoate anion (1555 cm(-1)) was observed at different regions without the interference from PG or silicone membrane. Benzoate anion, a charged species, was observed to permeate the membrane. The permeation of benzoate anion from sodium benzoate and polar ion-pairs of AMP and AMPD was very low in contrast to their high-saturated concentrations in PG as compared to the t-BA ion-pair. This indicated that benzoate anion preferentially permeates the membrane as an ion-pair rather than a single anion; otherwise its permeation should correspond to its concentration in PG instead of the lipophilicity of the ion-pairs. Additionally, the diffusion coefficient values of benzoic acid and benzoate anions through the treated and untreated membranes were not statistically different. PMID:15363507

  17. Endogenous fatty acids in olfactory hairs influence pheromone binding protein structure and function in Lymantria dispar.

    PubMed

    Nardella, Jason; Terrado, Mailyn; Honson, Nicolette S; Plettner, Erika

    2015-08-01

    The gypsy moth utilizes a pheromone, (7R,8S)-2-methyl-7,8-epoxyoctadecane, for mate location. The pheromone is detected by sensory hairs (sensilla) on the antennae of adult males. Sensilla contain the dendrites of olfactory neurons bathed in lymph, which contains pheromone binding proteins (PBPs). We have extracted and identified free fatty acids from lymph of sensory hairs, and we demonstrate that these function as endogenous ligands for gypsy moth PBP1 and PBP2. Homology modeling of both PBPs, and docking of fatty acids reveal multiple binding sites: one internal, the others external. Pheromone binding assays suggest that these fatty acids increase PBP-pheromone binding affinity. We show that fatty acid binding causes an increase in α-helix content in the N-terminal domain, but not in the C-terminal peptide of both proteins. The C-terminal peptide was shown to form a α-helix in a hydrophobic, homogeneous environment, but not in the presence of fatty acid micelles. Through partition assays we show that the fatty acids prevent adsorption of the pheromone on hydrophobic surfaces and facilitate pheromone partition into an aqueous phase. We propose that lymph is an emulsion of fatty acids and PBP that influence each other and thereby control the partition equilibria of hydrophobic odorants. PMID:26032337

  18. Salicylic acids

    PubMed Central

    Hayat, Shamsul; Irfan, Mohd; Wani, Arif; Nasser, Alyemeni; Ahmad, Aqil

    2012-01-01

    Salicylic acid is well known phytohormone, emerging recently as a new paradigm of an array of manifestations of growth regulators. The area unleashed yet encompassed the applied agriculture sector to find the roles to strengthen the crops against plethora of abiotic and biotic stresses. The skipped part of integrated picture, however, was the evolutionary insight of salicylic acid to either allow or discard the microbial invasion depending upon various internal factors of two interactants under the prevailing external conditions. The metabolic status that allows the host invasion either as pathogenesis or symbiosis with possible intermediary stages in close systems has been tried to underpin here. PMID:22301975

  19. Combined Experimental and Theoretical Study on the Formation of the Elusive 2-Methyl-1-silacycloprop-2-enylidene Molecule under Single Collision Conditions via Reactions of the Silylidyne Radical (SiH; X(2)Π) with Allene (H2CCCH2; X(1)A1) and D4-Allene (D2CCCD2; X(1)A1).

    PubMed

    Yang, Tao; Dangi, Beni B; Maksyutenko, Pavlo; Kaiser, Ralf I; Bertels, Luke W; Head-Gordon, Martin

    2015-12-17

    The crossed molecular beam reactions of the ground-state silylidyne radical (SiH; X(2)Π) with allene (H2CCCH2; X(1)A1) and D4-allene (D2CCCD2; X(1)A1) were carried out at collision energies of 30 kJ mol(-1). Electronic structure calculations propose that the reaction of silylidyne with allene has no entrance barrier and is initiated by silylidyne addition to the π electron density of allene either to one carbon atom (C1/C2) or to both carbon atoms simultaneously via indirect (complex forming) reaction dynamics. The initially formed addition complexes isomerize via two distinct reaction pathways, both leading eventually to a cyclic SiC3H5 intermediate. The latter decomposes through a loose exit transition state via an atomic hydrogen loss perpendicularly to the plane of the decomposing complex (sideways scattering) in an overall exoergic reaction (experimentally: -19 ± 13 kJ mol(-1); computationally: -5 ± 3 kJ mol(-1)). This hydrogen loss yields the hitherto elusive 2-methyl-1-silacycloprop-2-enylidene molecule (c-SiC3H4), which can be derived from the closed-shell cyclopropenylidene molecule (c-C3H2) by replacing a hydrogen atom with a methyl group and the carbene carbon atom by the isovalent silicon atom. The synthesis of the 2-methyl-1-silacycloprop-2-enylidene molecule in the bimolecular gas-phase reaction of silylidyne with allene enriches our understanding toward the formation of organosilicon species in the gas phase of the interstellar medium in particular via exoergic reactions of no entrance barrier. This facile route to 2-methyl-1-silacycloprop-2-enylidene via a silylidyne radical reaction with allene opens up a versatile approach to form hitherto poorly characterized silicon-bearing species in extraterrestrial environments; this reaction class might represent the missing link, leading from silicon-bearing radicals via organosilicon chemistry eventually to silicon-carbon-rich interstellar grains even in cold molecular clouds where temperatures are as

  20. Folic acid

    MedlinePlus

    ... disease called vitiligo, and an inherited disease called Fragile-X syndrome. It is also used for reducing harmful side ... to blood clots (ischemic stroke). Inherited disease called Fragile-X syndrome.Taking folic acid by mouth does not improve ...

  1. Acid rain

    SciTech Connect

    Not Available

    1984-06-01

    An overview is presented of acid rain and the problems it causes to the environment worldwide. The acidification of lakes and streams is having a dramatic effect on aquatic life. Aluminum, present in virtually all forest soils, leaches out readily under acid conditions and interferes with the gills of all fish, some more seriously than others. There is evidence of major damage to forests in European countries. In the US, the most severe forest damage appears to be in New England, New York's Adirondacks, and the central Appalachians. This small region is part of a larger area of the Northeast and Canada that appears to have more acid rainfall than the rest of the country. It is downwind from major coal burning states, which produce about one quarter of US SO/sub 2/ emissions and one sixth of nitrogen oxide emissions. Uncertainties exist over the causes of forest damage and more research is needed before advocating expensive programs to reduce rain acidity. The President's current budget seeks an expansion of research funds from the current $30 million per year to $120 million.

  2. Formic acid

    Integrated Risk Information System (IRIS)

    Formic acid ; CASRN 64 - 18 - 6 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarcinogenic Effect

  3. Selenious acid

    Integrated Risk Information System (IRIS)

    Selenious acid ; CASRN 7783 - 00 - 8 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarcinogenic E

  4. Benzoic acid

    Integrated Risk Information System (IRIS)

    Benzoic acid ; CASRN 65 - 85 - 0 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarcinogenic Effec

  5. Trichloroacetic acid

    Integrated Risk Information System (IRIS)

    Trichloroacetic acid ( TCA ) ; CASRN 76 - 03 - 9 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Nonca

  6. Dichloroacetic acid

    Integrated Risk Information System (IRIS)

    Dichloroacetic acid ; CASRN 79 - 43 - 6 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarcinogeni

  7. Acrylic acid

    Integrated Risk Information System (IRIS)

    Acrylic acid ( CASRN 79 - 10 - 7 ) Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarcinogenic Eff

  8. Cacodylic acid

    Integrated Risk Information System (IRIS)

    Cacodylic acid ; CASRN 75 - 60 - 5 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarcinogenic Eff

  9. Phosphoric acid

    Integrated Risk Information System (IRIS)

    Phosphoric acid ; CASRN 7664 - 38 - 2 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarcinogenic

  10. Stearic Acid

    ERIC Educational Resources Information Center

    Young, Jay A.

    2004-01-01

    A chemical laboratory information profile (CLIP) is presented for the chemical, stearic acid. The profile lists the chemical's physical and harmful characteristics, exposure limits, and symptoms of major exposure, for the benefit of teachers and students, who use the chemical in the laboratory.

  11. Crystal structure of ethyl (1RS,6SR)-4-(2-methyl-1H-imidazol-4-yl)-2-oxo-6-(2,3,5-tri­chloro­phen­yl)cyclo­hex-3-ene-1-carboxyl­ate

    PubMed Central

    Mohan, Billava J.; Sarojini, Balladka K.; Yathirajan, Hemmige S.; Rathore, Ravindranath; Glidewell, Christopher

    2016-01-01

    The title compound, C19H17Cl3N2O3, has been prepared in a cyclo­condensation reaction between 2,3,5-tri­chloro­benzaldehye and 4-acetyl-2-methyl-1H-imidazole. The cyclo­hexenone ring adopts an envelope conformation with the C atom substituted by the tri­chloro­phenyl ring as the flap. The mutually trans ester and aryl substituents both occupy equatorial sites. In the crystal, a combination of N—H⋯O and C—H⋯N hydrogen bonds links the mol­ecules into ribbons of edge-fused centrosymmetric rings, which enclose R 2 2(14) and R 4 4(16) alternate ring motifs, propagating along the b-axis direction. PMID:26870579

  12. Trichlorido{2-[2-(η5-cyclo­penta­dien­yl)-2-methyl­prop­yl]-1-trimethyl­silyl-1H-imidazole-κN 3}titanium(IV) tetra­hydro­furan hemisolvate

    PubMed Central

    Ge, Fang; Nie, Wanli; Borzov, Maxim V.; Churakov, Andrei V.

    2010-01-01

    The title compound, [Ti(C15H23N2Si)Cl3]·0.5C4H8O, has been prepared from {2-[2-(η5-cyclo­penta­dien­yl)-2-methyl­prop­yl]-1H-imidazolyl-κN 1}bis­(N,N-diethyl­amido-κN)titanium(IV), (C12H14N2)Ti(NEt2)2, by reaction with excess of Me3SiCl in tetra­hydro­furan (THF) at 353 K. The crystal structure contains THF as adduct solvent, disordered around a center of inversion. The presence of THF and the adduct ratio has been independently supported by 1H NMR spectroscopy. The coordination polyhedron of the Ti atom is distorted square-pyramidal, assuming the cyclo­penta­dienyl (Cp) ring occupies one coordination site. The Ti, Si and CH2 group C atoms only deviate slightly from the imidazole ring plane [by 0.021 (4), 0.133 (4) and 0.094 (4) Å, respectively]. Comparison of the principal geometric parameters with those of the few known structurally characterized analogues reveal small differences in bond lengths and angles at the Ti atom. The title complex is only stable in THF-d 8 in the presence of excess Me3SiCl, otherwise it exists in an equilibrium with equimolar amounts of dichlorido{2-[2-(η5-cyclo­penta­dien­yl)-2-methyl­prop­yl]-1H-imidazolyl-κN 3}titanium(IV) and chloro­trimethyl­silane. PMID:21579034

  13. Hydroxycarboxylic acids and salts

    DOEpatents

    Kiely, Donald E; Hash, Kirk R; Kramer-Presta, Kylie; Smith, Tyler N

    2015-02-24

    Compositions which inhibit corrosion and alter the physical properties of concrete (admixtures) are prepared from salt mixtures of hydroxycarboxylic acids, carboxylic acids, and nitric acid. The salt mixtures are prepared by neutralizing acid product mixtures from the oxidation of polyols using nitric acid and oxygen as the oxidizing agents. Nitric acid is removed from the hydroxycarboxylic acids by evaporation and diffusion dialysis.

  14. Some non-anomerically C-C-linked carbohydrate amino acids related to leucine-synthesis and structure determination.

    PubMed

    Steiner, Bohumil; Micová, Júlia; Koós, Miroslav; Langer, Vratislav; Gyepesová, Dalma

    2003-06-23

    (5'R)-5'-Isobutyl-5'-[methyl (4R)-2,3-O-isopropylidene-beta-L-erythrofuranosid-4-C-yl]-imidazolidin-2',4'-dione was synthesised starting from methyl 2,3-O-isopropylidene-alpha-D-lyxo-pentodialdo-1,4-furanoside via methyl 6-deoxy-6-isopropyl-2,3-O-isopropylidene-alpha-D-lyxo-hexofuranosid-5-ulose applying the Bucherer-Bergs reaction. Its 5'-R configuration was confirmed by X-ray crystallography. Corresponding alpha-amino acid-methyl (5R)-5-amino-5-C-carboxy-5,6-dideoxy-6-isopropyl-alpha-D-lyxo-hexofuranoside (alternative name: 2-[methyl (4R)-beta-L-erythrofuranosid-4-C-yl]-D-leucine) was obtained from the above hydantoin by acid hydrolysis of the isopropylidene group followed by basic hydrolysis of the hydantoin ring. Analogous derivatives with 5S configuration, formed in a minority, were also isolated and characterised. PMID:12801708

  15. Methylmalonic acid blood test

    MedlinePlus

    ... acid is a substance produced when proteins, called amino acids, in the body break down. The health care ... Cederbaum S, Berry GT. Inborn errors of carbohydrate, ammonia, amino acid, and organic acid metabolism. In: Gleason CA, Devaskar ...

  16. Folic acid - test

    MedlinePlus

    Folic acid is a type of B vitamin. This article discusses the test to measure the amount of folic acid in the blood. ... that may interfere with test results, including folic acid supplements. Drugs that can decrease folic acid measurements ...

  17. Uric acid urine test

    MedlinePlus

    The uric acid urine test measures the level of uric acid in urine. Uric acid level can also be checked using a blood ... help determine the cause of a high uric acid level in the blood. It may also be ...

  18. Methylmalonic acid blood test

    MedlinePlus

    The methylmalonic acid blood test measures the amount of methylmalonic acid in the blood. ... Methylmalonic acid is a substance produced when proteins, called amino acids, in the body break down. The health care ...

  19. Folic Acid and Pregnancy

    MedlinePlus

    ... 5 Things to Know About Zika & Pregnancy Folic Acid and Pregnancy KidsHealth > For Parents > Folic Acid and ... before conception and during early pregnancy . About Folic Acid Folic acid, sometimes called folate, is a B ...

  20. Understanding Acid Rain

    ERIC Educational Resources Information Center

    Damonte, Kathleen

    2004-01-01

    The term acid rain describes rain, snow, or fog that is more acidic than normal precipitation. To understand what acid rain is, it is first necessary to know what an acid is. Acids can be defined as substances that produce hydrogen ions (H+), when dissolved in water. Scientists indicate how acidic a substance is by a set of numbers called the pH…

  1. New bioactive fatty acids

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Many oxygenated fatty acids are bioactive compounds. Nocardia cholesterolicum and Flavobacterium DS5 convert oleic acid to 10 hydroxy stearic acid and linoleic acid to 10-hydroxy-12(Z)-octadecanoic acid. Pseudomonas aeruginosa PR3 converts oleic acid to the new compounds, 7,10-dihydroxy-8(E)-octad...

  2. New Bioactive Fatty Acids

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Many oxygenated fatty acids are bioactive compounds. Nocardia cholesterolicum and Flavobacterium DS5 convert oleic acid to 10 hydroxy stearic acid and linoleic acid to 10-hydroxy-12(Z)-octadecanoic acid. Pseudomonas aeruginosa PR3 converts oleic acid to new compounds, 7,10-dihydroxy-8(E)-octadecen...

  3. Degradation of CYANEX 301 in Contact with Nitric Acid Media

    SciTech Connect

    Philippe Marc; Radu Custelcean; Gary S. Groenewold; John R. Klaehn; Dean R. Peterman; Laetitia H. Delmau

    2012-10-01

    The nature of the degradation product obtained upon contacting CYANEX 301 (bis(2,4,4-trimethylpentyl)dithiophosphinic acid) with nitric acid has been elucidated and found to be a disulfide derivative. The first step to the degradation of CYANEX 301 in toluene has been studied using 31P{1H} NMR after being contacted with nitric acid media. The spectrum of the degradation product exhibits a complex multiplet around dP = 80 ppm. A succession of purifications of CYANEX 301 has resulted in single crystals of the acidic form and the corresponding ammonium salt. Unlike the original CYANEX 301, which consists of a complex diastereomeric mixture displaying all possible combinations of chiral orientations at the 2-methyl positions, the purified crystals were shown by single-crystal X-ray diffraction to be racemates, containing 50:50 mixtures of the [R;R] and [S;S] diastereomers. The comparison between the 31P {1H} NMR spectra of the degradation products resulting from the diastereomerically pure CYANEX 301 and the original diastereomeric mixture has elucidated the influence of the isomeric composition on the multiplicity of the 31P {1H} NMR peak. These NMR data indicate the initial degradation leads to a disulfide-bridged condensation product displaying multiple resonances due to phosphorus–phosphorus coupling, which is caused by the inequivalence of the two P atoms as a result of their different chirality. A total of nine different NMR resonances, six of which display phosphorus–phosphorus coupling, could be assigned, and the identity of the peaks corresponding to phosphorus atoms coupled to each other was confirmed by 31P {1H} homodecoupled NMR analysis.

  4. Pyruvate decarboxylase catalyzes decarboxylation of branched-chain 2-oxo acids but is not essential for fusel alcohol production by Saccharomyces cerevisiae.

    PubMed

    ter Schure, E G; Flikweert, M T; van Dijken, J P; Pronk, J T; Verrips, C T

    1998-04-01

    The fusel alcohols 3-methyl-1-butanol, 2-methyl-1-butanol, and 2-methyl-propanol are important flavor compounds in yeast-derived food products and beverages. The formation of these compounds from branched-chain amino acids is generally assumed to occur via the Ehrlich pathway, which involves the concerted action of a branched-chain transaminase, a decarboxylase, and an alcohol dehydrogenase. Partially purified preparations of pyruvate decarboxylase (EC 4.1.1.1) have been reported to catalyze the decarboxylation of the branched-chain 2-oxo acids formed upon transamination of leucine, isoleucine, and valine. Indeed, in a coupled enzymatic assay with horse liver alcohol dehydrogenase, cell extracts of a wild-type Saccharomyces cerevisiae strain exhibited significant decarboxylation rates with these branched-chain 2-oxo acids. Decarboxylation of branched-chain 2-oxo acids was not detectable in cell extracts of an isogenic strain in which all three PDC genes had been disrupted. Experiments with cell extracts from S. cerevisiae mutants expressing a single PDC gene demonstrated that both PDC1- and PDC5-encoded isoenzymes can decarboxylate branched-chain 2-oxo acids. To investigate whether pyruvate decarboxylase is essential for fusel alcohol production by whole cells, wild-type S. cerevisiae and an isogenic pyruvate decarboxylase-negative strain were grown on ethanol with a mixture of leucine, isoleucine, and valine as the nitrogen source. Surprisingly, the three corresponding fusel alcohols were produced in both strains. This result proves that decarboxylation of branched-chain 2-oxo acids via pyruvate decarboxylase is not an essential step in fusel alcohol production. PMID:9546164

  5. Structure-activity relationships of anthraquinone derivatives derived from bromaminic acid as inhibitors of ectonucleoside triphosphate diphosphohydrolases (E-NTPDases)

    PubMed Central

    Baqi, Younis; Weyler, Stefanie; Iqbal, Jamshed; Zimmermann, Herbert

    2008-01-01

    Reactive blue 2 (RB-2) had been characterized as a relatively potent ectonucleoside triphosphate diphosphohydrolase (E-NTPDase) inhibitor with some selectivity for NTPDase3. In search for the pharmacophore and to analyze structure-activity relationships we synthesized a series of truncated derivatives and analogs of RB-2, including 1-amino-2-sulfo-4-ar(alk)ylaminoanthraquinones, 1-amino-2-methyl-4-arylaminoanthraquinones, 1-amino-4-bromoanthraquinone 2-sulfonic acid esters and sulfonamides, and bis-(1-amino-4-bromoanthraquinone) sulfonamides, and investigated them in preparations of rat NTPDase1, 2, and 3 using a capillary electrophoresis assay. Several 1-amino-2-sulfo-4-ar(alk)ylaminoanthraquinone derivatives inhibited E-NTPDases in a concentration-dependent manner. The 2-sulfonate group was found to be required for inhibitory activity, since 2-methyl-substituted derivatives were inactive. 1-Amino-2-sulfo-4-p-chloroanilinoanthraquinone (18) was identified as a nonselective competitive blocker of NTPDases1, 2, and 3 (Ki 16–18 μM), while 1-amino-2-sulfo-4-(2-naphthylamino)anthraquinone (21) was a potent inhibitor with preference for NTPDase1 (Ki 0.328 μM) and NTPDase3 (Ki 2.22 μM). Its isomer, 1-amino-2-sulfo-4-(1-naphthylamino)anthraquinone (20), was a potent and selective inhibitor of rat NTPDase3 (Ki 1.5 μM). PMID:18528783

  6. A Combined Experimental and Theoretical Study on the Formation of the 2-Methyl-1-silacycloprop-2-enylidene Molecule via the Crossed Beam Reactions of the Silylidyne Radical (SiH; X(2)Π) with Methylacetylene (CH3CCH; X(1)A1) and D4-Methylacetylene (CD3CCD; X(1)A1).

    PubMed

    Yang, Tao; Dangi, Beni B; Kaiser, Ralf I; Bertels, Luke W; Head-Gordon, Martin

    2016-07-14

    The bimolecular gas-phase reactions of the ground-state silylidyne radical (SiH; X(2)Π) with methylacetylene (CH3CCH; X(1)A1) and D4-methylacetylene (CD3CCD; X(1)A1) were explored at collision energies of 30 kJ mol(-1) under single-collision conditions exploiting the crossed molecular beam technique and complemented by electronic structure calculations. These studies reveal that the reactions follow indirect scattering dynamics, have no entrance barriers, and are initiated by the addition of the silylidyne radical to the carbon-carbon triple bond of the methylacetylene molecule either to one carbon atom (C1; [i1]/[i2]) or to both carbon atoms concurrently (C1-C2; [i3]). The collision complexes [i1]/[i2] eventually isomerize via ring-closure to the c-SiC3H5 doublet radical intermediate [i3], which is identified as the decomposing reaction intermediate. The hydrogen atom is emitted almost perpendicularly to the rotational plane of the fragmenting complex resulting in a sideways scattering dynamics with the reaction being overall exoergic by -12 ± 11 kJ mol(-1) (experimental) and -1 ± 3 kJ mol(-1) (computational) to form the cyclic 2-methyl-1-silacycloprop-2-enylidene molecule (c-SiC3H4; p1). In line with computational data, experiments of silylidyne with D4-methylacetylene (CD3CCD; X(1)A1) depict that the hydrogen is emitted solely from the silylidyne moiety but not from methylacetylene. The dynamics are compared to those of the related D1-silylidyne (SiD; X(2)Π)-acetylene (HCCH; X(1)Σg(+)) reaction studied previously in our group, and from there, we discovered that the methyl group acts primarily as a spectator in the title reaction. The formation of 2-methyl-1-silacycloprop-2-enylidene under single-collision conditions via a bimolecular gas-phase reaction augments our knowledge of the hitherto poorly understood silylidyne (SiH; X(2)Π) radical reactions with small hydrocarbon molecules leading to the synthesis of organosilicon molecules in cold molecular

  7. METABOLIC FUNCTION OF BRANCHED-CHAIN VOLATILE FATTY ACIDS, GROWTH FACTORS FOR RUMINOCOCCI II.

    PubMed Central

    Allison, M. J.; Bryant, M. P.; Katz, I.; Keeney, M.

    1962-01-01

    Allison, M. J. (Dairy Cattle Research Branch, USDA, Beltsville, Md.), M. P. Bryant, I. Katz, and M. Keeney. Metabolic function of branched-chain volatile fatty acids, growth factors for ruminococci. II. Biosynthesis of higher branched-chain fatty acids and aldehydes. J. Bacteriol. 83:1084–1093. 1962.—A number of strains of rumen bacteria require branched-chain volatile fatty acids for growth. A strain of Ruminococcus flavefaciens that requires either isovalerate or isobutyrate incorporates radioactive carbon from isovalerate-1-C14 and isovalerate-3-C14 into leucine and into the lipid fraction of the cells. Evidence obtained by both paper and gas chromatography indicated that most of the label in the lipid of cells grown in isovalerate-1-C14 was in a branched-chain 15-carbon fatty acid, with some in a 17-carbon acid; about 7.5% of the C14 was recovered in a branched-chain 15-carbon aldehyde. The aldehydes were in the phospholipid fraction and were presumably present as plasmalogen. A strain of R. albus was shown to require isobutyrate, 2-methyl-n-butyrate, or 2-ketoisovalerate for growth. This strain did not incorporate appreciable C14 from isovalerate-1-C14 or isovalerate-3-C14. When grown in a medium containing isobutyrate-1-C14, most of the cellular C14 was found in the lipid fraction. Analysis of the lipid demonstrated that the label was present mainly as branched-chain 14-carbon and 16-carbon fatty acids, with 11% of the C14 present in 14- and 16-carbon carbonyl compounds, presumably branched-chain aldehydes. Branched-chain 14-, 15-, and 16-carbon fatty acids are major components of the lipids of these rumen bacteria. The possibility that these acids and aldehydes, which are found in ruminant body and milk lipids, may be of microbial origin is discussed. PMID:13860622

  8. Crystal structure of (+)-methyl (E)-3-[(2S,4S,5R)-2-amino-5-hy­droxy­meth­yl-2-tri­chloro­methyl-1,3-dioxolan-4-yl]-2-methyl­prop-2-enoate

    PubMed Central

    Oishi, Takeshi; Yasushima, Daichi; Yuasa, Kihiro; Sato, Takaaki; Chida, Noritaka

    2016-01-01

    In the title compound, C10H14Cl3NO5, the five-membered dioxolane ring adopts an envelope conformation. The C atom at the flap, which is bonded to the hy­droxy­methyl substituent, deviates from the mean plane of other ring atoms by 0.357 (5) Å. There are two intra­molecular hydrogen bonds (O—H⋯N and N—H⋯O) between the hy­droxy and amino groups, so that O- and N-bound H atoms involved in these hydrogen bonds are each disordered with equal occupancies of 0.50. The methyl 2-methyl­prop-2-enoate substituent also shows a disordered structure over two sets of sites with refined occupancies of 0.482 (5) and 0.518 (5). In the crystal, mol­ecules are connected into a dimer by an O—H⋯O hydrogen bond. The dimers are further linked by N—H⋯O, C—H⋯N and C—H⋯O inter­actions, extending a sheet structure parallel to (01). PMID:27006804

  9. Bioactive Fatty Acids

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Oxygenated fatty acids are useful as specialty chemicals, plasticizers, and biomedicals. Microbial enzymes convert fatty acids to mono-, di-, and trihydroxy fatty acid products. Among them, Bacillus megaterium ALA2 converted n-6 and n-3 PUFAs to many new oxygenated fatty acids. Linoleic acid was ...

  10. N-tert-Butyl-2-methyl­propanamide

    PubMed Central

    Kluge, Kelly A.; Fridyland, Diana; MacBeth, Cora E.; Hardcastle, Kenneth I.

    2011-01-01

    The title compound, C8H17NO, crystallizes with two independent mol­ecules in the asymmetric unit. In the crystal, inter­molecular N—H⋯O hydrogen bonding is observed between neighboring mol­ecules, forming continuous mol­ecular chains along the c-axis direction. PMID:22091159

  11. Phase 2 Methyl Iodide Deep-Bed Adsorption Tests

    SciTech Connect

    Soelberg, Nick; Watson, Tony

    2014-09-01

    Nuclear fission produces fission products (FPs) and activation products, including iodine-129, which could evolve into used fuel reprocessing facility off-gas systems, and could require off-gas control to limit air emissions to levels within acceptable emission limits. Research, demonstrations, and some reprocessing plant experience have indicated that diatomic iodine can be captured with efficiencies high enough to meet regulatory requirements. Research on the capture of organic iodides has also been performed, but to a lesser extent. Several questions remain open regarding the capture of iodine bound in organic compounds. Deep-bed methyl iodide adsorption testing has progressed according to a multi-laboratory methyl iodide adsorption test plan. This report summarizes the second phase of methyl iodide adsorption work performed according to this test plan using the deep-bed iodine adsorption test system at the Idaho National Laboratory (INL), performed during the second half of Fiscal Year (FY) 2014. Test results continue to show that methyl iodide adsorption using AgZ can achieve total iodine decontamination factors (DFs, ratios of uncontrolled and controlled total iodine levels) above 1,000, until breakthrough occurred. However, mass transfer zone depths are deeper for methyl iodide adsorption compared to diatomic iodine (I2) adsorption. Methyl iodide DFs for the Ag Aerogel test adsorption efficiencies were less than 1,000, and the methyl iodide mass transfer zone depth exceeded 8 inches. Additional deep-bed testing and analyses are recommended to (a) expand the data base for methyl iodide adsorption under various conditions specified in the methyl iodide test plan, and (b) provide more data for evaluating organic iodide reactions and reaction byproducts for different potential adsorption conditions.

  12. N-tert-Butyl-2-methyl-propanamide.

    PubMed

    Kluge, Kelly A; Fridyland, Diana; Macbeth, Cora E; Hardcastle, Kenneth I

    2011-08-01

    The title compound, C(8)H(17)NO, crystallizes with two independent mol-ecules in the asymmetric unit. In the crystal, inter-molecular N-H⋯O hydrogen bonding is observed between neighboring mol-ecules, forming continuous mol-ecular chains along the c-axis direction. PMID:22091159

  13. Phenolic analogues of diastereoisomeric 2-methyl reversed esters of pethidine.

    PubMed

    Casy, A F; Dewar, G H; Pascoe, R A

    1989-03-01

    The preparation and stereochemical characterization of alpha- and beta-isomers of 1,2-dimethyl-4-m-hydroxyphenyl-4-propionyloxypiperidine are described. Both the alpha (axial 4-aryl/chair) and beta (equatorial 4-aryl/chair) isomers were of low potency or inactive in mice antinociceptive tests. Shortcomings of the alpha-isomer as a model for the 4-arylpiperidine moiety of morphine are discussed. PMID:2568454

  14. Uric acid test (image)

    MedlinePlus

    Uric acid urine test is performed to check for the amount of uric acid in urine. Urine is collected over a 24 ... testing. The most common reason for measuring uric acid levels is in the diagnosis or treatment of ...

  15. Amino Acid Metabolism Disorders

    MedlinePlus

    ... defects & other health conditions > Amino acid metabolism disorders Amino acid metabolism disorders E-mail to a friend Please ... baby’s newborn screening may include testing for certain amino acid metabolism disorders. These are rare health conditions that ...

  16. Plasma amino acids

    MedlinePlus

    Amino acids blood test ... types of methods used to determine the individual amino acid levels in the blood. ... test is done to measure the level of amino acids in the blood. An increased level of a ...

  17. Stomach acid test

    MedlinePlus

    Gastric acid secretion test ... of the cells in the stomach to release acid. The stomach contents are then removed and analyzed. ... 3.5). These numbers are converted to actual acid production in units of milliequivalents per hour in ...

  18. Azelaic Acid Topical

    MedlinePlus

    Azelaic acid gel is used to clear the bumps, lesions, and swelling caused by rosacea (a skin disease that ... redness, flushing, and pimples on the face). Azelaic acid cream is used to treat acne. Azelaic acid ...

  19. Facts about Folic Acid

    MedlinePlus

    ... Information For... Media Policy Makers Facts About Folic Acid Language: English Español (Spanish) Recommend on Facebook Tweet ... of the baby's brain and spine. About folic acid Folic acid is a B vitamin. Our bodies ...

  20. Acid Lipase Disease

    MedlinePlus

    ... Awards Enhancing Diversity Find People About NINDS NINDS Acid Lipase Disease Information Page Synonym(s): Cholesterol Ester Storage ... Trials Related NINDS Publications and Information What is Acid Lipase Disease ? Acid lipase disease or deficiency occurs ...

  1. Pharmacological activation of lysophosphatidic acid receptors regulates erythropoiesis

    PubMed Central

    Lin, Kuan-Hung; Ho, Ya-Hsuan; Chiang, Jui-Chung; Li, Meng-Wei; Lin, Shi-Hung; Chen, Wei-Min; Chiang, Chi-Ling; Lin, Yu-Nung; Yang, Ya-Jan; Chen, Chiung-Nien; Lu, Jenher; Huang, Chang-Jen; Tigyi, Gabor; Yao, Chao-Ling; Lee, Hsinyu

    2016-01-01

    Lysophosphatidic acid (LPA), a growth factor-like phospholipid, regulates numerous physiological functions, including cell proliferation and differentiation. In a previous study, we have demonstrated that LPA activates erythropoiesis by activating the LPA 3 receptor subtype (LPA3) under erythropoietin (EPO) induction. In the present study, we applied a pharmacological approach to further elucidate the functions of LPA receptors during red blood cell (RBC) differentiation. In K562 human erythroleukemia cells, knockdown of LPA2 enhanced erythropoiesis, whereas knockdown of LPA3 inhibited RBC differentiation. In CD34+ human hematopoietic stem cells (hHSC) and K526 cells, the LPA3 agonist 1-oleoyl-2-methyl-sn-glycero-3-phosphothionate (2S-OMPT) promoted erythropoiesis, whereas the LPA2 agonist dodecyl monophosphate (DMP) and the nonlipid specific agonist GRI977143 (GRI) suppressed this process. In zebrafish embryos, hemoglobin expression was significantly increased by 2S-OMPT treatment but was inhibited by GRI. Furthermore, GRI treatment decreased, whereas 2S-OMPT treatment increased RBC counts and amount of hemoglobin level in adult BALB/c mice. These results indicate that LPA2 and LPA3 play opposing roles during RBC differentiation. The pharmacological activation of LPA receptor subtypes represent a novel strategies for augmenting or inhibiting erythropoiesis. PMID:27244685

  2. Synthesis of carboranyl amino acids, hydantoins, and barbiturates

    SciTech Connect

    Wyzlic, I.M.; Tjarks, W.; Soloway, A.H.

    1996-07-31

    The syntheses of three novel boronated hydantoins, 5-(o-carboran-1-ylmethyl)hydantoin, 14, the tetraphenylphosphonium salt of 7-(hydantoin-5-ylmethyl)dodecahydro-7,8-dicarba-nido-undecaborate, 15, 5-(o-carboran-1-ylmethyl)-2-thiohydantoin, 16, and two new barbiturates, 5,5-bis(but-2-ynyl)barbiturate, 18, and 5,5-bis[(2-methyl-0-carboran-1-yl)methyl]barbiturate, 20, are described. Hydantoins 14-16 were synthesized from o-carboranylalanine (Car, 13). The detailed synthesis of Car and two other carborane-containing amino acids, O-(o-carboran-1-ylmethyl)tyrosine (CBT, 5a) and p-(o-carboran-1-yl)phenylalanine (CBPA, 5b), presented earlier as a communication, {sup 16} are also described. Hydantoin 14 and barbiturates 18 and 20 were tested for their potential anticonvulsant activity. Initial qualitative screening showed moderate activities for hydantoin 14 and barbiturate 18. Barbiturate 20 had no activity. Compound 14 appeared to be nontoxic at doses of 300 mg/kg (mice, ip) and 50 mg/kg (rats, oral). However, 18 was very toxic under similar conditions.

  3. Pharmacological activation of lysophosphatidic acid receptors regulates erythropoiesis.

    PubMed

    Lin, Kuan-Hung; Ho, Ya-Hsuan; Chiang, Jui-Chung; Li, Meng-Wei; Lin, Shi-Hung; Chen, Wei-Min; Chiang, Chi-Ling; Lin, Yu-Nung; Yang, Ya-Jan; Chen, Chiung-Nien; Lu, Jenher; Huang, Chang-Jen; Tigyi, Gabor; Yao, Chao-Ling; Lee, Hsinyu

    2016-01-01

    Lysophosphatidic acid (LPA), a growth factor-like phospholipid, regulates numerous physiological functions, including cell proliferation and differentiation. In a previous study, we have demonstrated that LPA activates erythropoiesis by activating the LPA 3 receptor subtype (LPA3) under erythropoietin (EPO) induction. In the present study, we applied a pharmacological approach to further elucidate the functions of LPA receptors during red blood cell (RBC) differentiation. In K562 human erythroleukemia cells, knockdown of LPA2 enhanced erythropoiesis, whereas knockdown of LPA3 inhibited RBC differentiation. In CD34(+) human hematopoietic stem cells (hHSC) and K526 cells, the LPA3 agonist 1-oleoyl-2-methyl-sn-glycero-3-phosphothionate (2S-OMPT) promoted erythropoiesis, whereas the LPA2 agonist dodecyl monophosphate (DMP) and the nonlipid specific agonist GRI977143 (GRI) suppressed this process. In zebrafish embryos, hemoglobin expression was significantly increased by 2S-OMPT treatment but was inhibited by GRI. Furthermore, GRI treatment decreased, whereas 2S-OMPT treatment increased RBC counts and amount of hemoglobin level in adult BALB/c mice. These results indicate that LPA2 and LPA3 play opposing roles during RBC differentiation. The pharmacological activation of LPA receptor subtypes represent a novel strategies for augmenting or inhibiting erythropoiesis. PMID:27244685

  4. Folic acid - test

    MedlinePlus

    ... folic acid measurements include: Alcohol Aminosalicylic acid Birth control pills Estrogens Tetracyclines Ampicillin Chloramphenicol Erythromycin Methotrexate Penicillin Aminopterin Phenobarbital Phenytoin Drugs to treat malaria

  5. Oxalic acid poisoning

    MedlinePlus

    Symptoms of oxalic acid poisoning include: Abdominal pain Burns and blisters where the acid contacted the skin Collapse Convulsions Mouth pain Shock Throat pain Tremors (unintentional trembling) Vomiting

  6. 2-Methyl-6-(4,4,10,13,14-penta­methyl-3-oxo-2,3,4,5,6,7,10,11,12,13,14,15,16,17-tetra­deca­hydro-1H-cyclo­penta­[a]phenanthren-17-yl)hept-2-enoic acid

    PubMed Central

    Arfan, Mohammad; Rauf, Abdur; Tahir, M. Nawaz; Ali, Mumtaz; Uddin, Ghias

    2011-01-01

    In the title compound, C30H46O3, an isolation product of Pistacia integerima Stewart, the five-membered ring is nearly in the envelope form. A 6-carb­oxy­hept-5-en-2-yl group is attached to the five-membered ring. An S(6) ring motif is formed due to intra­molecular C—H⋯O hydrogen bonding. In the crystal, inter­molecular O—H⋯O hydrogen bonds form carboxyl­ate dimers with R 2 2(8) ring motifs. PMID:21522454

  7. FORMATION OF 2-METHYL TETROLS AND 2-METHYLGLYCERIC ACID IN SECONDARY ORGANIC AEROSOL FROM LABORATORY IRRADIATED ISOPRENE/NO X/SO 2/AIR MIXTURES AND THEIR DETECTION IN AMBIENT PM 2.5 SAMPLES COLLECTED IN THE EASTERN UNITED STATES

    EPA Science Inventory

    A series of isoprene/NOx/air irradiation experiments, carried out in both the absence and presence of SO2, were conducted to assess whether isoprene contributes to secondary organic aerosol (SOA) formation. In the absence of SO2 , the SOA yield of 0.002 was low. However, in th...

  8. Acid distribution in phosphoric acid fuel cells

    SciTech Connect

    Okae, I.; Seya, A.; Umemoto, M.

    1996-12-31

    Electrolyte acid distribution among each component of a cell is determined by capillary force when the cell is not in operation, but the distribution under the current load conditions had not been clear so far. Since the loss of electrolyte acid during operation is inevitable, it is necessary to store enough amount of acid in every cell. But it must be under the level of which the acid disturbs the diffusion of reactive gases. Accordingly to know the actual acid distribution during operation in a cell is very important. In this report, we carried out experiments to clarify the distribution using small single cells.

  9. Preparation and characterization of poly(2-acrylamido-2-methylpropane-sulfonic acid)/Chitosan hydrogel using gamma irradiation and its application in wastewater treatment

    NASA Astrophysics Data System (ADS)

    Gad, Y. H.

    2008-09-01

    Radiation grafting of chitosan with 2-acrylamido-2-methyl propane sulfonic acid (AMPS) has been successfully performed. The effect of absorbed dose (kGy) and the chitosan:AMPS ratio on graft hydrogelization was studied. The structure of the prepared hydrogel was confirmed using infrared spectroscopy (IR). Thermal properties were simultaneously studied by thermogravimetric analysis (TGA). The effect of the polymerization variables on the swelling % of the prepared hydrogel was investigated. The highest equilibrium degree of swelling (38.6 g/g) and gel % (94.7%) of the prepared chitosan-AMPS hydrogel was at 40% AMPS and absorbed dose of 10 kGy. The removal of methylene blue, acid red dye, Cd (II) and Cr (III) from composed wastewater was also investigated. The effect of pH, the chitosan:AMPS ratio and the concentration of the pollutant on the adsorption process were studied.

  10. Lipase-catalyzed fractionation of conjugated linoleic acid isomers.

    PubMed

    Haas, M J; Kramer, J K; McNeill, G; Scott, K; Foglia, T A; Sehat, N; Fritsche, J; Mossoba, M M; Yurawecz, M P

    1999-09-01

    The abilities of lipases produced by the fungus Geotrichum candidum to selectively fractionate mixtures of conjugated linoleic acid (CLA) isomers during esterification of mixed CLA free fatty acids and during hydrolysis of mixed CLA methyl esters were examined. The enzymes were highly selective for cis-9,trans-11-18:2. A commercial CLA methyl ester preparation, containing at least 12 species representing four positional CLA isomers, was incubated in aqueous solution with either a commercial G. candidum lipase preparation (Amano GC-4) or lipase produced from a cloned high-selectivity G. candidum lipase B gene. In both instances selective hydrolysis of the cis-9,trans-11-18:2 methyl ester occurred, with negligible hydrolysis of other CLA isomers. The content of cis-9, trans-11-18:2 in the resulting free fatty acid fraction was between 94 (lipase B reaction) and 77% (GC-4 reaction). The commercial CLA mixture contained only trace amounts of trans-9,cis-11-18:2, and there was no evidence that this isomer was hydrolyzed by the enzyme. Analogous results were obtained with these enzymes in the esterification in organic solvent of a commercial preparation of CLA free fatty acids containing at least 12 CLA isomers. In this case, G. candidum lipase B generated a methyl ester fraction that contained >98% cis-9,trans-11-18:2. Geotrichum candidum lipases B and GC-4 also demonstrated high selectivity in the esterification of CLA with ethanol, generating ethyl ester fractions containing 96 and 80%, respectively, of the cis-9,trans-11 isomer. In a second set of experiments, CLA synthesized from pure linoleic acid, composed essentially of two isomers, cis-9,trans-11 and trans-10,cis-12, was utilized. This was subjected to esterification with octanol in an aqueous reaction system using Amano GC-4 lipase as catalyst. The resulting ester fraction contained up to 97% of the cis-9,trans-11 isomer. After adjustment of the reaction conditions, a concentration of 85% trans-10,cis-12

  11. Comparison crystal structure conformations of two structurally related biphenyl analogues: 4,4′-bis­[3-(pyrrolidin-1-yl)prop-1-yn-1-yl]-1,1′-biphenyl and 4,4′-bis­{3-[(S)-2-methyl­pyrrolidin-1-yl]prop-1-yn-1-yl}-1,1′-biphen­yl

    PubMed Central

    Wan, Anqi; Penthala, Narsimha Reddy; Fifer, E. Kim; Parkin, Sean; Crooks, Peter A.

    2015-01-01

    The title compounds, C26H28N2, (I), and C28H32N2, (II), were designed based on the structure of the potent α9α10 nicotinic acetyl­choline receptor antagonist ZZ161C {1,1′-[[1,1′-biphen­yl]-4,4′-diylbis(prop-2-yne-3,1-di­yl)]bis­(3,4-di­methyl­pyridin-1-ium) bromide}. In order to improve the druglikeness properties of ZZ161C for potential oral administration, the title compounds (I) and (II) were prepared by coupling 4,4′-bis­(3-bromo­prop-1-yn-1-yl)-1,1′-biphenyl with pyrrol­idine, (I), and (S)-2-methyl­pyrrolidine, (II), respectively, in aceto­nitrile at room temperature. The asymmetric unit of (I) contains two half mol­ecules that each sit on sites of crystallographic inversion. As a result, the biphenyl ring systems in compound (I) are coplanar. The biphenyl ring system in compound (II), however, has a dihedral angle of 28.76 (11)°. In (I), the two independent mol­ecules differ in the orientation of the pyrrolidine ring (the nitro­gen lone pair points towards the biphenyl rings in one mol­ecule, but away from the rings in the other). The torsion angles about the ethynyl groups between the planes of the phenyl rings and the pyrrolidine ring N atoms are 84.15 (10) and −152.89 (10)°. In compound (II), the corresponding torsion angles are 122.0 (3) and 167.0 (3)°, with the nitro­gen lone pairs at both ends of the mol­ecule directed away from the central biphenyl rings. PMID:26594393

  12. Pharmacokinetics and pharmacodynamics of DPC 333 ((2R)-2-((3R)-3-amino-3{4-[2-methyl-4-quinolinyl) methoxy] phenyl}-2-oxopyrrolidinyl)-N-hydroxy-4-methylpentanamide)), a potent and selective inhibitor of tumor necrosis factor alpha-converting enzyme in rodents, dogs, chimpanzees, and humans.

    PubMed

    Qian, Mingxin; Bai, Stephen A; Brogdon, Bernice; Wu, Jing-Tao; Liu, Rui-Qin; Covington, Maryanne B; Vaddi, Kris; Newton, Robert C; Fossler, Michael J; Garner, C Edwin; Deng, Yuzhong; Maduskuie, Thomas; Trzaskos, James; Duan, James J-W; Decicco, Carl P; Christ, David D

    2007-10-01

    DPC 333 ((2R)-2-((3R)-3-amino-3{4-[2-methyl-4-quinolinyl) methoxy] phenyl}-2-oxopyrrolidinyl)-N-hydroxy-4-methylpentanamide)) is a potent and selective inhibitor of tumor necrosis factor (TNF)-alpha-converting enzyme (TACE). It significantly inhibits lipopolysaccharide-induced soluble TNF-alpha production in blood from rodents, chimpanzee, and human, with IC(50) values ranging from 17 to 100 nM. In rodent models of endotoxemia, DPC 333 inhibited the production of TNF-alpha in a dose-dependent manner, with an oral ED(50) ranging from 1.1 to 6.1 mg/kg. Oral dosing of DPC 333 at 5.5 mg/kg daily for 2 weeks in a rat collagen antibody-induced arthritis model suppressed the maximal response by approximately 50%. DPC 333 was distributed widely to tissues including the synovium, the site of action for antiarthritic drugs. Pharmacokinetic and pharmacodynamic studies in chimpanzee revealed a systemic clearance of 0.4 l/h/kg, a V(ss) of 0.6 l/kg, an oral bioavailability of 17%, and an ex vivo IC(50) for the suppression of TNF-alpha production of 55 nM (n = 1). In a phase I clinical trial with male volunteers after single escalating doses of oral DPC 333, the terminal half-life was between 3 and 6 h and the ex vivo IC(50) for suppressing TNF-alpha production was 113 nM. Measurement of the suppression of TNF-alpha production ex vivo may serve as a good biomarker in evaluating the therapeutic efficacy of TACE inhibitors. Overall, the pharmacological profiles of DPC 333 support the notion that suppression of TNF-alpha with TACE inhibitors like DPC 333 may provide a novel approach in the treatment of various inflammatory diseases including rheumatoid arthritis, via control of excessive TNF-alpha production. PMID:17656469

  13. Phtytochemical Studies and Quantitative HPLC Analysis of Rosmarinic Acid and Luteolin 5-O-β-D-Glucopyranoside on Thymus praecox subsp. grossheimii var. grossheimii.

    PubMed

    Sevindik, Handan Gokben; Ozgen, Ufuk; Atila, Alptug; Ozturk Er, Handan; Kazaz, Cavit; Duman, Hayri

    2015-01-01

    Thymus praecox ssp. grossheimii (RONNIGER) JALAS var. grossheimii (Lamiaceae) is used as an herbal tea for cold, stomachache, cough, and infections in Turkey. There are no phytochemical studies on this species. We performed phytochemical studies and quantitative analysis of rosmarinic acid and luteolin 5-O-β-D-glucopyranoside in the methanol extract of the plant. Several chromatographic methods were used for the isolation of major compounds. HPLC methods were applied for quantitative analysis of rosmarinic acid and luteolin 5-O-β-D-glucopyranoside in the methanol extract. In this study, ursolic acid (1), oleanolic acid (2), methyl rosmarinate (3), ethyl rosmarinate (4), rosmarinic acid (5), luteolin 5-O-β-D-glucopyranoside (6), and thymoquinol 2,5-O-β-diglucopyranoside (7) were isolated from the aerial parts of the plant. The relative contents of rosmarinic acid and luteolin 5-O-β-D-glucopyranoside in the extract were 15.2 and 57.8 mg/g of dry weight, respectively. Compounds isolated from this plant and the contents of rosmarinic acid and luteolin 5-O-β-D-glucopyranoside provided reasonable evidence for the traditional usages of this plant. PMID:26329865

  14. Characterization of 2-(methylamino)alkanoic acid capacity to restrict blood–brain phenylalanine transport in Pahenu2 mice: Preliminary findings✩

    PubMed Central

    Vogel, Kara R.; Arning, Erland; Wasek, Brandi L.; Bottiglieri, Teodoro; Gibson, K. Michael

    2014-01-01

    Background Our laboratory seeks a pharmacotherapeutic intervention for PKU that utilizes non-physiological amino acids (NPAAs) to block the accumulation of phenylalanine (Phe) in the brain. In previous studies (Vogel et al. 2013), methylation of the amino group of 2-aminoisobutyrate (AIB) provided an enhanced degree of selectivity for Phe restriction into the brain of Pahenu2 mice in comparison to unmethylated AIB, leading to the hypothesis that 2-(methylamino)alkanoic acid analogs of AIB might represent targeted inhibitors of Phe accretion into the brain. Methods Pahenu2 and control mice were intraperitoneally administered (500–750 mg/kg body weight, once daily; standard 19% protein diet) AIB, methyl AIB (MAIB), isovaline, and two MAIB analogs, 2-methyl-2-(methylamino)butanoic (MeVal) and 3-methyl-2-(methylamino)pentanoic (MePent) acids for one week, followed by brain and blood isolation for amino acid analyses using UPLC. Results In the brain, AIB significantly reduced Phe accretion in Pahenu2 mice, while MeVal significantly improved glutamine and aspartic acids. Four of five test compounds improved brain threonine and arginine levels. AIB, MAIB and IsoVal significantly reduced blood Phe, with no effect of any drug intervention on other sera amino acids. Conclusions Further evaluation of AIB and the 2-(methylamino)alkanoic acids as inhibitors of brain Phe accumulation in Pahenu2 mice is warranted, with more detailed evaluations of route of administration, combinatorial intervention, and detailed toxicity studies. PMID:23999161

  15. Metabolism of propionic acid to a novel acyl-coenzyme A thioester by mammalian cell lines and platelets[S

    PubMed Central

    Snyder, Nathaniel W.; Basu, Sankha S.; Worth, Andrew J.; Mesaros, Clementina; Blair, Ian A.

    2015-01-01

    Metabolism of propionate involves the activated acyl-thioester propionyl-CoA intermediate. We employed LC-MS/MS, LC-selected reaction monitoring/MS, and LC-high-resolution MS to investigate metabolism of propionate to acyl-CoA intermediates. We discovered that propionyl-CoA can serve as a precursor to the direct formation of a new six-carbon mono-unsaturated acyl-CoA. Time course and dose-response studies in human hepatocellular carcinoma HepG2 cells demonstrated that the six-carbon mono-unsaturated acyl-CoA was propionate-dependent and underwent further metabolism over time. Studies utilizing [13C1]propionate and [13C3]propionate suggested a mechanism of fatty acid synthesis, which maintained all six-carbon atoms from two propionate molecules. Metabolism of 2,2-[2H2]propionate to the new six-carbon mono-unsaturated acyl-CoA resulted in the complete loss of two deuterium atoms, indicating modification at C2 of the propionyl moiety. Coelution experiments and isotopic tracer studies confirmed that the new acyl-CoA was trans-2-methyl-2-pentenoyl-CoA. Acyl-CoA profiles following treatment of HepG2 cells with mono-unsaturated six-carbon fatty acids also supported this conclusion. Similar results were obtained with human platelets, mouse hepatocellular carcinoma Hepa1c1c7 cells, human bronchoalveolar carcinoma H358 cells, and human colon adenocarcinoma LoVo cells. Interestingly, trans-2-methyl-2-pentenoyl-CoA corresponds to a previously described acylcarnitine tentatively described in patients with propionic and methylmalonic acidemia. We have proposed a mechanism for this metabolic route consistent with all of the above findings. PMID:25424005

  16. Metabolism of propionic acid to a novel acyl-coenzyme A thioester by mammalian cell lines and platelets.

    PubMed

    Snyder, Nathaniel W; Basu, Sankha S; Worth, Andrew J; Mesaros, Clementina; Blair, Ian A

    2015-01-01

    Metabolism of propionate involves the activated acyl-thioester propionyl-CoA intermediate. We employed LC-MS/MS, LC-selected reaction monitoring/MS, and LC-high-resolution MS to investigate metabolism of propionate to acyl-CoA intermediates. We discovered that propionyl-CoA can serve as a precursor to the direct formation of a new six-carbon mono-unsaturated acyl-CoA. Time course and dose-response studies in human hepatocellular carcinoma HepG2 cells demonstrated that the six-carbon mono-unsaturated acyl-CoA was propionate-dependent and underwent further metabolism over time. Studies utilizing [(13)C1]propionate and [(13)C3]propionate suggested a mechanism of fatty acid synthesis, which maintained all six-carbon atoms from two propionate molecules. Metabolism of 2,2-[(2)H2]propionate to the new six-carbon mono-unsaturated acyl-CoA resulted in the complete loss of two deuterium atoms, indicating modification at C2 of the propionyl moiety. Coelution experiments and isotopic tracer studies confirmed that the new acyl-CoA was trans-2-methyl-2-pentenoyl-CoA. Acyl-CoA profiles following treatment of HepG2 cells with mono-unsaturated six-carbon fatty acids also supported this conclusion. Similar results were obtained with human platelets, mouse hepatocellular carcinoma Hepa1c1c7 cells, human bronchoalveolar carcinoma H358 cells, and human colon adenocarcinoma LoVo cells. Interestingly, trans-2-methyl-2-pentenoyl-CoA corresponds to a previously described acylcarnitine tentatively described in patients with propionic and methylmalonic acidemia. We have proposed a mechanism for this metabolic route consistent with all of the above findings. PMID:25424005

  17. Acid tolerance in amphibians

    SciTech Connect

    Pierce, B.A.

    1985-04-01

    Studies of amphibian acid tolerance provide information about the potential effects of acid deposition on amphibian communities. Amphibians as a group appear to be relatively acid tolerant, with many species suffering increased mortality only below pH 4. However, amphibians exhibit much intraspecific variation in acid tolerance, and some species are sensitive to even low levels of acidity. Furthermore, nonlethal effects, including depression of growth rates and increases in developmental abnormalities, can occur at higher pH.

  18. Activity-Based Probe for N-Acylethanolamine Acid Amidase.

    PubMed

    Romeo, Elisa; Ponzano, Stefano; Armirotti, Andrea; Summa, Maria; Bertozzi, Fabio; Garau, Gianpiero; Bandiera, Tiziano; Piomelli, Daniele

    2015-09-18

    N-Acylethanolamine acid amidase (NAAA) is a lysosomal cysteine hydrolase involved in the degradation of saturated and monounsaturated fatty acid ethanolamides (FAEs), a family of endogenous lipid signaling molecules that includes oleoylethanolamide (OEA) and palmitoylethanolamide (PEA). Among the reported NAAA inhibitors, α-amino-β-lactone (3-aminooxetan-2-one) derivatives have been shown to prevent FAE hydrolysis in innate-immune and neural cells and to reduce reactions to inflammatory stimuli. Recently, we disclosed two potent and selective NAAA inhibitors, the compounds ARN077 (5-phenylpentyl-N-[(2S,3R)-2-methyl-4-oxo-oxetan-3-yl]carbamate) and ARN726 (4-cyclohexylbutyl-N-[(S)-2-oxoazetidin-3-yl]carbamate). The former is active in vivo by topical administration in rodent models of hyperalgesia and allodynia, while the latter exerts systemic anti-inflammatory effects in mouse models of lung inflammation. In the present study, we designed and validated a derivative of ARN726 as the first activity-based protein profiling (ABPP) probe for the in vivo detection of NAAA. The newly synthesized molecule 1 is an effective in vitro and in vivo click-chemistry activity based probe (ABP), which is able to capture the catalytically active form of NAAA in Human Embryonic Kidney 293 (HEK293) cells overexpressing human NAAA as well as in rat lung tissue. Competitive ABPP with 1 confirmed that ARN726 and ARN077 inhibit NAAA in vitro and in vivo. Compound 1 is a useful new tool to identify activated NAAA both in vitro and in vivo and to investigate the physiological and pathological roles of this enzyme. PMID:26102511

  19. Toxicity of adipic acid.

    PubMed

    Kennedy, Gerald L

    2002-05-01

    Adipic acid has very low acute toxicity in rats with an LD50 > 5000 mg/kg. Adipic acid produced mild to no skin irritation on intact guinea pig skin as a 50% concentration in propylene glycol; it was not a skin sensitizer. Adipic acid caused mild conjunctival irritation in washed rabbit eyes; in unwashed rabbit eyes, there was mild conjunctival irritation, minimal iritis, but no corneal effects. Adipic acid dust may irritate the mucous membranes of the lungs and nose. In a 2-year feeding study, rats fed adipic acid at concentrations up to 5% in the diet exhibited only weight loss. Adipic acid is not genetically active in a wide variety of assay systems. Adipic acid caused no developmental toxicity in mice, rats, rabbits, or hamsters when administered orally. Adipic acid is partially metabolized in humans; the balance is eliminated unchanged in the urine. Adipic acid is slightly to moderately toxic to fish, daphnia, and algae in acute tests. PMID:12024802

  20. Acid Thunder: Acid Rain and Ancient Mesoamerica

    ERIC Educational Resources Information Center

    Kahl, Jonathan D. W.; Berg, Craig A.

    2006-01-01

    Much of Mesoamerica's rich cultural heritage is slowly eroding because of acid rain. Just as water dissolves an Alka-Seltzer tablet, acid rain erodes the limestone surfaces of Mexican archaeological sites at a rate of about one-half millimeter per century (Bravo et al. 2003). A half-millimeter may not seem like much, but at this pace, a few…

  1. Quantity of acid in acid fog

    SciTech Connect

    Deal, W.J.

    1983-07-01

    This communication notes the actual magnitude of the acidity in acidic fog particles and suggests a possible line of inquiry into the health effects of such fog so that it can be determined whether a typical fog is detrimental or beneficial relative to dry air.

  2. [Amino acids in saliva].

    PubMed

    Klinger, G; Gruhn, K

    1984-01-01

    Total amino acids in saliva and free and peptide-bound amino acids from 21 saliva samples were determined. The contents of amino acids was 25 mmol/1; total nitrogen content was 78-80 mmol/1. Amino acids consist of Prolin in 25%. Some patients were examined before and after application of the depot estrogen ethinyl estradiosulfonat, which stimulates the assimilation of protein. After application, amino acids increased and the authors found a shift between the single amino acids. Estrogen medication induced an increase in proteins with the character of collagens. Clinical effects are discussed. (author's modified) PMID:6240853

  3. Conformational analysis of a trihydroxylated derivative of cinnamic acid—a combined Raman spectroscopy and Ab initio study

    NASA Astrophysics Data System (ADS)

    Fiuza, S. M.; Van Besien, E.; Milhazes, N.; Borges, F.; Marques, M. P. M.

    2004-05-01

    A conformational analysis of 3-(3,4,5-trihydroxyphenyl)-2-propenoic acid (3,4,5-trihydroxycinnamic acid, THPPE), a trihydroxylated cinnamic acid analogous to caffeic acid (a natural compound often present in diet), was carried out by Raman spectroscopy coupled to Ab initio MO calculations. Apart from the optimised geometrical parameters for the most stable conformers of this compound, and for one of its dimeric species, the corresponding harmonic vibrational frequencies, as well as potential-energy profiles for rotation around several bonds within the molecule, were obtained. Twenty one distinct conformers were found for THPPE, the lowest energy ones—THPPE 1 and THPPE 2—displaying a completely planar geometry. The conformational preferences of this system were thus found to be mainly ruled by the stabilising effect of π-electron delocalisation. At the light of these results, a complete assignment of the corresponding solid state Raman spectra was performed.

  4. Hydrochloric acid poisoning

    MedlinePlus

    Hydrochloric acid is a clear, poisonous liquid. It is highly corrosive, which means it immediately causes severe damage, ... discusses poisoning due to swallowing or breathing in hydrochloric acid. This article is for information only. Do NOT ...

  5. Omega-3 Fatty Acids

    MedlinePlus

    Omega-3 fatty acids are used together with lifestyle changes (diet, weight-loss, exercise) to reduce the amount ... the blood in people with very high triglycerides. Omega-3 fatty acids are in a class of medications ...

  6. Omega-6 Fatty Acids

    MedlinePlus

    Omega-6 fatty acids are types of fats. Some types are found in vegetable oils, including corn, evening primrose seed, safflower, and soybean oils. Other types of omega-6 fatty acids are found in black currant seed, borage seed, ...

  7. Zoledronic Acid Injection

    MedlinePlus

    Zoledronic acid (Reclast) is used to prevent or treat osteoporosis (condition in which the bones become thin and weak ... of life,' end of regular menstrual periods). Zoledronic acid (Reclast) is also used to treat osteoporosis in ...

  8. Aminolevulinic Acid Topical

    MedlinePlus

    Aminolevulinic acid is used in combination with photodynamic therapy (PDT; special blue light) to treat actinic keratoses (small crusty ... skin cancer) of the face or scalp. Aminolevulinic acid is in a class of medications called photosensitizing ...

  9. Acid-fast stain

    MedlinePlus

    The acid-fast stain is a laboratory test that determines if a sample of tissue, blood, or other body ... dye. The slide is then washed with an acid solution and a different stain is applied. Bacteria ...

  10. Uric acid - blood

    MedlinePlus

    Uric acid is a chemical created when the body breaks down substances called purines. Purines are found in some ... dried beans and peas, and beer. Most uric acid dissolves in blood and travels to the kidneys. ...

  11. Hydrochloric acid poisoning

    MedlinePlus

    Hydrochloric acid is a clear, poisonous liquid. It is highly corrosive, which means it immediately causes severe damage, such ... poisoning due to swallowing or breathing in hydrochloric acid. This article is for information only. Do NOT ...

  12. Omega-6 Fatty Acids

    MedlinePlus

    ... types of fats. Some types are found in vegetable oils, including corn, evening primrose seed, safflower, and soybean ... from studying specific omega-6 fatty acids or plant oils containing omega-6 fatty acids. See the separate ...

  13. Uric Acid Test

    MedlinePlus

    ... limited. Home Visit Global Sites Search Help? Uric Acid Share this page: Was this page helpful? Also known as: Serum Urate; UA Formal name: Uric Acid Related tests: Synovial Fluid Analysis , Kidney Stone Analysis , ...

  14. Acid-fast stain

    MedlinePlus

    ... this page: //medlineplus.gov/ency/article/003766.htm Acid-fast stain To use the sharing features on this page, please enable JavaScript. The acid-fast stain is a laboratory test that determines ...

  15. Aminocaproic Acid Injection

    MedlinePlus

    Aminocaproic acid injection is used to control bleeding that occurs when blood clots are broken down too quickly. This ... the baby is ready to be born). Aminocaproic acid injection is also used to control bleeding in ...

  16. Deoxycholic Acid Injection

    MedlinePlus

    Deoxycholic acid injection is used to improve the appearance and profile of moderate to severe submental fat ('double chin'; fatty tissue located under the chin). Deoxycholic acid injection is in a class of medications called ...

  17. Methylmalonic Acid Test

    MedlinePlus

    ... limited. Home Visit Global Sites Search Help? Methylmalonic Acid Share this page: Was this page helpful? Also known as: MMA Formal name: Methylmalonic Acid Related tests: Vitamin B12 and Folate , Homocysteine , Intrinsic ...

  18. Fatty acid analogs

    DOEpatents

    Elmaleh, David R.; Livni, Eli

    1985-01-01

    In one aspect, a radioactively labeled analog of a fatty acid which is capable of being taken up by mammalian tissue and which exhibits an in vivo beta-oxidation rate below that with a corresponding radioactively labeled fatty acid.

  19. Boric acid poisoning

    MedlinePlus

    ... boric acid poisoning usually occurs when someone swallows powdered roach-killing products that contain the chemical. Chronic ... vein (IV) Medicines to treat symptoms Note: Activated charcoal does not effectively treat (absorb) boric acid. For ...

  20. Lactic acid test

    MedlinePlus

    ... this page: //medlineplus.gov/ency/article/003507.htm Lactic acid test To use the sharing features on this page, please enable JavaScript. Lactic acid is mainly produced in muscle cells and red ...

  1. PRODUCTION OF TRIFLUOROACETIC ACID

    DOEpatents

    Haworth, W.N.; Stacey, M.

    1949-07-19

    A method is given for the production of improved yields of trifluoroacetic acid. The compound is prepared by oxidizing m-aminobenzotrifluoride with an alkali metal or alkaline earth metal permanganate at a temperature in the range of 80 deg C to 100 deg C while dissolved ln a mixture of water with glacial acetic acid and/or trifluoroacetic acid. Preferably a mixture of water and trifluoroacetic acid ls used as the solvent.

  2. Plant fatty acid hydroxylases

    DOEpatents

    Somerville, Chris; Broun, Pierre; van de Loo, Frank

    2001-01-01

    This invention relates to plant fatty acyl hydroxylases. Methods to use conserved amino acid or nucleotide sequences to obtain plant fatty acyl hydroxylases are described. Also described is the use of cDNA clones encoding a plant hydroxylase to produce a family of hydroxylated fatty acids in transgenic plants. In addition, the use of genes encoding fatty acid hydroxylases or desaturases to alter the level of lipid fatty acid unsaturation in transgenic plants is described.

  3. Quantity of acid in acid fog

    SciTech Connect

    Deal, W.J.

    1983-07-01

    The chemical composition of fog particles has become of considerable interest, because of both the possibility of interpreting atmospheric- chemistry processes in fog particles in terms of the principles of aqueous chemistry and the potential health effects of species present in fog particles. The acidity of fog particles has received wide attention. This communication noted the actual magnitude of the excess acidity in acidic fog particles and suggested a possible line of inquiry into the health effects of such fog so that it can be determined whether a typical fog is detrimental or beneficial relative to dry air. (DP)

  4. The Acid Rain Reader.

    ERIC Educational Resources Information Center

    Stubbs, Harriett S.; And Others

    A topic which is often not sufficiently dealt with in elementary school textbooks is acid rain. This student text is designed to supplement classroom materials on the topic. Discussed are: (1) "Rain"; (2) "Water Cycle"; (3) "Fossil Fuels"; (4) "Air Pollution"; (5) "Superstacks"; (6) "Acid/Neutral/Bases"; (7) "pH Scale"; (8) "Acid Rain"; (9)…

  5. What Is Acid Rain?

    ERIC Educational Resources Information Center

    Likens, Gene E.

    2004-01-01

    Acid rain is the collective term for any type of acidified precipitation: rain, snow, sleet, and hail, as well as the presence of acidifying gases, particles, cloud water, and fog in the atmosphere. The increased acidity, primarily from sulfuric and nitric acids, is generated as a by-product of the combustion of fossil fuels such as coal and oil.…

  6. Acid Rain Study Guide.

    ERIC Educational Resources Information Center

    Hunger, Carolyn; And Others

    Acid rain is a complex, worldwide environmental problem. This study guide is intended to aid teachers of grades 4-12 to help their students understand what acid rain is, why it is a problem, and what possible solutions exist. The document contains specific sections on: (1) the various terms used in conjunction with acid rain (such as acid…

  7. [alpha]-Oxocarboxylic Acids

    ERIC Educational Resources Information Center

    Kerber, Robert C.; Fernando, Marian S.

    2010-01-01

    Several [alpha]-oxocarboxylic acids play key roles in metabolism in plants and animals. However, there are inconsistencies between the structures as commonly portrayed and the reported acid ionization constants, which result because the acids are predominantly hydrated in aqueous solution; that is, the predominant form is RC(OH)[subscript 2]COOH…

  8. A Doped Polyaniline Modified Electrode Amperometric Biosensor for Gluconic Acid Determination in Grapes

    PubMed Central

    Albanese, Donatella; Malvano, Francesca; Sannini, Adriana; Pilloton, Roberto; Di Matteo, Marisa

    2014-01-01

    In winemaking gluconic acid is an important marker for quantitative evaluation of grape infection by Botrytis cinerea. A screen-printed amperometric bienzymatic sensor for the determination of gluconic acid based on gluconate kinase (GK) and 6-phospho-D-gluconate dehydrogenase (6PGDH) coimmobilized onto polyaniline/poly (2-acrylamido-2-methyl-1-propanesulfonic acid; PANI-PAAMPSA) is reported in this study. The conductive polymer electrodeposed on the working electrode surface allowed the detection of NADH at low potential (0.1 V) with a linear range from 4 × 10−3 to 1 mM (R2 = 0.99) and a sensitivity of 419.44 nA·mM−1. The bienzymatic sensor has been optimized with regard to GK/6PGDH enzymatic unit ratio and ATP/NADP+ molar ratio which resulted equal to 0.33 and 1.2, respectively. Under these conditions a sensitivity of 255.2 nA·mM−1, a limit of detection of 5 μM and a Relative Standard Deviation (RSD) of 4.2% (n = 5) have been observed. Finally, the biosensor has been applied for gluconic acid measurements in must grape samples and the matrix effect has been taken into consideration. The results have been compared with those obtained on the same samples with a commercial kit based on a spectrophotometric enzyme assay and were in good agreement, showing the capability of the bienzymatic PANI-PAAMPSA biosensor for gluconic acid measurements and thus for the evaluation of Botrytis cinerea infection in grapes. PMID:24960084

  9. Cleavage of nucleic acids

    DOEpatents

    Prudent, James R.; Hall, Jeff G.; Lyamichev, Victor L.; Brow, Mary Ann D.; Dahlberg, James E.

    2007-12-11

    The present invention relates to means for the detection and characterization of nucleic acid sequences, as well as variations in nucleic acid sequences. The present invention also relates to methods for forming a nucleic acid cleavage structure on a target sequence and cleaving the nucleic acid cleavage structure in a site-specific manner. The structure-specific nuclease activity of a variety of enzymes is used to cleave the target-dependent cleavage structure, thereby indicating the presence of specific nucleic acid sequences or specific variations thereof.

  10. Amino acid analysis

    NASA Technical Reports Server (NTRS)

    Winitz, M.; Graff, J. (Inventor)

    1974-01-01

    The process and apparatus for qualitative and quantitative analysis of the amino acid content of a biological sample are presented. The sample is deposited on a cation exchange resin and then is washed with suitable solvents. The amino acids and various cations and organic material with a basic function remain on the resin. The resin is eluted with an acid eluant, and the eluate containing the amino acids is transferred to a reaction vessel where the eluant is removed. Final analysis of the purified acylated amino acid esters is accomplished by gas-liquid chromatographic techniques.

  11. Editorial: Acid precipitation

    SciTech Connect

    1995-09-01

    This editorial focuses on acid rain and the history of public and governmental response to acid rain. Comments on a book by Gwineth Howell `Acid Rain and Acid Waters` are included. The editor feels that Howells has provide a service to the environmental scientific community, with a textbook useful to a range of people, as well as a call for decision makers to learn from the acid rain issue and use it as a model for more sweeping global environmental issues. A balance is needed among several parameters such as level of evidence, probability that the evidence will lead to a specific direction and the cost to the global community. 1 tab.

  12. Cleavage of nucleic acids

    SciTech Connect

    Prudent, James R.; Hall, Jeff G.; Lyamichev, Victor I.; Brow; Mary Ann D.; Dahlberg, James E.

    2010-11-09

    The present invention relates to means for the detection and characterization of nucleic acid sequences, as well as variations in nucleic acid sequences. The present invention also relates to methods for forming a nucleic acid cleavage structure on a target sequence and cleaving the nucleic acid cleavage structure in a site-specific manner. The structure-specific nuclease activity of a variety of enzymes is used to cleave the target-dependent cleavage structure, thereby indicating the presence of specific nucleic acid sequences or specific variations thereof.

  13. Cleavage of nucleic acids

    DOEpatents

    Prudent, James R.; Hall, Jeff G.; Lyamichev, Victor I.; Brow, Mary Ann D.; Dahlberg, James E.

    2000-01-01

    The present invention relates to means for the detection and characterization of nucleic acid sequences, as well as variations in nucleic acid sequences. The present invention also relates to methods for forming a nucleic acid cleavage structure on a target sequence and cleaving the nucleic acid cleavage structure in a site-specific manner. The structure-specific nuclease activity of a variety of enzymes is used to cleave the target-dependent cleavage structure, thereby indicating the presence of specific nucleic acid sequences or specific variations thereof.

  14. Nucleic acid detection assays

    DOEpatents

    Prudent, James R.; Hall, Jeff G.; Lyamichev, Victor I.; Brow, Mary Ann; Dahlberg, James E.

    2005-04-05

    The present invention relates to means for the detection and characterization of nucleic acid sequences, as well as variations in nucleic acid sequences. The present invention also relates to methods for forming a nucleic acid cleavage structure on a target sequence and cleaving the nucleic acid cleavage structure in a site-specific manner. The structure-specific nuclease activity of a variety of enzymes is used to cleave the target-dependent cleavage structure, thereby indicating the presence of specific nucleic acid sequences or specific variations thereof.

  15. Nucleic acid detection compositions

    DOEpatents

    Prudent, James R.; Hall, Jeff G.; Lyamichev, Victor I.; Brow, Mary Ann; Dahlberg, James L.

    2008-08-05

    The present invention relates to means for the detection and characterization of nucleic acid sequences, as well as variations in nucleic acid sequences. The present invention also relates to methods for forming a nucleic acid cleavage structure on a target sequence and cleaving the nucleic acid cleavage structure in a site-specific manner. The structure-specific nuclease activity of a variety of enzymes is used to cleave the target-dependent cleavage structure, thereby indicating the presence of specific nucleic acid sequences or specific variations thereof.

  16. Acidic Ionic Liquids.

    PubMed

    Amarasekara, Ananda S

    2016-05-25

    Ionic liquid with acidic properties is an important branch in the wide ionic liquid field and the aim of this article is to cover all aspects of these acidic ionic liquids, especially focusing on the developments in the last four years. The structural diversity and synthesis of acidic ionic liquids are discussed in the introduction sections of this review. In addition, an unambiguous classification system for various types of acidic ionic liquids is presented in the introduction. The physical properties including acidity, thermo-physical properties, ionic conductivity, spectroscopy, and computational studies on acidic ionic liquids are covered in the next sections. The final section provides a comprehensive review on applications of acidic ionic liquids in a wide array of fields including catalysis, CO2 fixation, ionogel, electrolyte, fuel-cell, membrane, biomass processing, biodiesel synthesis, desulfurization of gasoline/diesel, metal processing, and metal electrodeposition. PMID:27175515

  17. Nucleic acid detection kits

    DOEpatents

    Hall, Jeff G.; Lyamichev, Victor I.; Mast, Andrea L.; Brow, Mary Ann; Kwiatkowski, Robert W.; Vavra, Stephanie H.

    2005-03-29

    The present invention relates to means for the detection and characterization of nucleic acid sequences, as well as variations in nucleic acid sequences. The present invention also relates to methods for forming a nucleic acid cleavage structure on a target sequence and cleaving the nucleic acid cleavage structure in a site-specific manner. The structure-specific nuclease activity of a variety of enzymes is used to cleave the target-dependent cleavage structure, thereby indicating the presence of specific nucleic acid sequences or specific variations thereof. The present invention further relates to methods and devices for the separation of nucleic acid molecules based on charge. The present invention also provides methods for the detection of non-target cleavage products via the formation of a complete and activated protein binding region. The invention further provides sensitive and specific methods for the detection of nucleic acid from various viruses in a sample.

  18. Demospongic Acids Revisited

    PubMed Central

    Kornprobst, Jean-Michel; Barnathan, Gilles

    2010-01-01

    The well-known fatty acids with a Δ5,9 unsaturation system were designated for a long period as demospongic acids, taking into account that they originally occurred in marine Demospongia sponges. However, such acids have also been observed in various marine sources with a large range of chain-lengths (C16–C32) and from some terrestrial plants with short acyl chains (C18–C19). Finally, the Δ5,9 fatty acids appear to be a particular type of non-methylene-interrupted fatty acids (NMA FAs). This article reviews the occurrence of these particular fatty acids in marine and terrestrial organisms and shows the biosynthetic connections between Δ5,9 fatty acids and other NMI FAs. PMID:21116406

  19. Process for the preparation of lactic acid and glyceric acid

    DOEpatents

    Jackson, James E [Haslett, MI; Miller, Dennis J [Okemos, MI; Marincean, Simona [Dewitt, MI

    2008-12-02

    Hexose and pentose monosaccharides are degraded to lactic acid and glyceric acid in an aqueous solution in the presence of an excess of a strongly anionic exchange resin, such as AMBERLITE IRN78 and AMBERLITE IRA400. The glyceric acid and lactic acid can be separated from the aqueous solution. Lactic acid and glyceric acid are staple articles of commerce.

  20. Microorganisms for producing organic acids

    SciTech Connect

    Pfleger, Brian Frederick; Begemann, Matthew Brett

    2014-09-30

    Organic acid-producing microorganisms and methods of using same. The organic acid-producing microorganisms comprise modifications that reduce or ablate AcsA activity or AcsA homolog activity. The modifications increase tolerance of the microorganisms to such organic acids as 3-hydroxypropionic acid, acrylic acid, propionic acid, lactic acid, and others. Further modifications to the microorganisms increase production of such organic acids as 3-hydroxypropionic acid, lactate, and others. Methods of producing such organic acids as 3-hydroxypropionic acid, lactate, and others with the modified microorganisms are provided. Methods of using acsA or homologs thereof as counter-selectable markers are also provided.

  1. Acid-Base Homeostasis

    PubMed Central

    Nakhoul, Nazih; Hering-Smith, Kathleen S.

    2015-01-01

    Acid-base homeostasis and pH regulation are critical for both normal physiology and cell metabolism and function. The importance of this regulation is evidenced by a variety of physiologic derangements that occur when plasma pH is either high or low. The kidneys have the predominant role in regulating the systemic bicarbonate concentration and hence, the metabolic component of acid-base balance. This function of the kidneys has two components: reabsorption of virtually all of the filtered HCO3− and production of new bicarbonate to replace that consumed by normal or pathologic acids. This production or generation of new HCO3− is done by net acid excretion. Under normal conditions, approximately one-third to one-half of net acid excretion by the kidneys is in the form of titratable acid. The other one-half to two-thirds is the excretion of ammonium. The capacity to excrete ammonium under conditions of acid loads is quantitatively much greater than the capacity to increase titratable acid. Multiple, often redundant pathways and processes exist to regulate these renal functions. Derangements in acid-base homeostasis, however, are common in clinical medicine and can often be related to the systems involved in acid-base transport in the kidneys. PMID:26597304

  2. Highly efficient enzymatic synthesis of an ascorbyl unstaturated fatty acid ester with ecofriendly biomass-derived 2-methyltetrahydrofuran as cosolvent.

    PubMed

    Hu, Ying-Dan; Qin, Ye-Zhi; Li, Ning; Zong, Min-Hua

    2014-01-01

    Enzymatic synthesis of ascorbyl undecylenate, an unsaturated fatty acid ester of ascorbic acid, was reported with biomass-derived 2-methyltetrahydrofuran (MeTHF) as the cosolvent. Of the immobilized lipases tested, Candida antarctica lipase B (CAL-B) showed the highest activity for enzymatic synthesis of ascorbyl undecylenate. Effect of reaction media on the enzymatic reaction was studied. The cosolvent mixture, t-butanol-MeTHF (1:4, v/v) proved to be the optimal medium, in which not only ascorbic acid had moderate solubility, but also CAL-B showed a high activity, thus addressing the major problem of the solvent conflict for dissolving substrate and keeping satisfactory enzyme activity. In addition, the enzyme was much more stable in MeTHF and t-butanol-MeTHF (1:4) than in previously widely used organic solvents, t-butanol, 2-methyl-2-butanol, and acetone. The much higher initial reaction rate in this cosolvent mixture may be rationalized by the much lower apparent activation energy of this enzymatic reaction (26.6 vs. 38.1-39.1 kJ/mol) and higher enzyme catalytic efficiency (Vmax /Km , 8.4 vs. 1.3-1.4 h(-1) ). Ascorbyl undecylenate was obtained with the yields of 84-89% and 6-regioselectivity of >99% in t-butanol-MeTHF (1:4) at supersaturated substrate concentrations (60 and 100 mM) after 5-8 h. PMID:24891225

  3. The Changes in Color, Soluble Sugars, Organic Acids, Anthocyanins and Aroma Components in "Starkrimson" during the Ripening Period in China.

    PubMed

    Liu, Yulian; Chen, Nianlai; Ma, Zonghuan; Che, Fei; Mao, Juan; Chen, Baihong

    2016-01-01

    "Starkrimson" is a traditional apple cultivar that was developed a long time ago and was widely cultivated in the arid region of the northern Wei River of China. However, little information regarding the quality characteristics of "Starkrimson" fruit has been reported in this area. To elucidate these characteristics, the color, soluble sugars, organic acids, anthocyanins and aroma components were measured during the ripening period through the use of high performance liquid chromatography (HPLC) and gas chromatography-mass spectrometry (GC-MS). The results indicated that the changes in anthocyanin contents took place later than the changes in the Commission International Eclairage (CIE) parameters. Meanwhile, cyanidin 3-galactoside (cy3-gal), fructose, sucrose, glucose and malic acid were the primary organic compounds, and 1-butanol-2-methyl-acetate, 2-hexenal and 1-hexanol were the most abundant aroma components in the skin. Furthermore, rapidly changing soluble sugars and organic acid synchronization took place in the early ripening period, while rapidly changing aroma components occurred later, on the basis of fresh weight. This result suggested that the production of aroma components might be a useful index of apple maturity. PMID:27338331

  4. Citric Acid Alternative to Nitric Acid Passivation

    NASA Technical Reports Server (NTRS)

    Lewis, Pattie L. (Compiler)

    2013-01-01

    The Ground Systems Development and Operations GSDO) Program at NASA John F. Kennedy Space Center (KSC) has the primary objective of modernizing and transforming the launch and range complex at KSC to benefit current and future NASA programs along with other emerging users. Described as the launch support and infrastructure modernization program in the NASA Authorization Act of 2010, the GSDO Program will develop and implement shared infrastructure and process improvements to provide more flexible, affordable, and responsive capabilities to a multi-user community. In support of the GSDO Program, the purpose of this project is to demonstratevalidate citric acid as a passivation agent for stainless steel. Successful completion of this project will result in citric acid being qualified for use as an environmentally preferable alternative to nitric acid for passivation of stainless steel alloys in NASA and DoD applications.

  5. USGS Tracks Acid Rain

    USGS Publications Warehouse

    Gordon, John D.; Nilles, Mark A.; Schroder, LeRoy J.

    1995-01-01

    The U.S. Geological Survey (USGS) has been actively studying acid rain for the past 15 years. When scientists learned that acid rain could harm fish, fear of damage to our natural environment from acid rain concerned the American public. Research by USGS scientists and other groups began to show that the processes resulting in acid rain are very complex. Scientists were puzzled by the fact that in some cases it was difficult to demonstrate that the pollution from automobiles and factories was causing streams or lakes to become more acidic. Further experiments showed how the natural ability of many soils to neutralize acids would reduce the effects of acid rain in some locations--at least as long as the neutralizing ability lasted (Young, 1991). The USGS has played a key role in establishing and maintaining the only nationwide network of acid rain monitoring stations. This program is called the National Atmospheric Deposition Program/National Trends Network (NADP/NTN). Each week, at approximately 220 NADP/NTN sites across the country, rain and snow samples are collected for analysis. NADP/NTN site in Montana. The USGS supports about 72 of these sites. The information gained from monitoring the chemistry of our nation's rain and snow is important for testing the results of pollution control laws on acid rain.

  6. Recovery of organic acids

    DOEpatents

    Verser, Dan W.; Eggeman, Timothy J.

    2009-10-13

    A method is disclosed for the recovery of an organic acid from a dilute salt solution in which the cation of the salt forms an insoluble carbonate salt. A tertiary amine and CO.sub.2 are introduced to the solution to form the insoluble carbonate salt and a complex between the acid and an amine. A water immiscible solvent, such as an alcohol, is added to extract the acid/amine complex from the dilute salt solution to a reaction phase. The reaction phase is continuously dried and a product between the acid and the solvent, such as an ester, is formed.

  7. Recovery of organic acids

    SciTech Connect

    Verser, Dan W.; Eggeman, Timothy J.

    2011-11-01

    A method is disclosed for the recovery of an organic acid from a dilute salt solution in which the cation of the salt forms an insoluble carbonate salt. A tertiary amine and CO.sub.2 are introduced to the solution to form the insoluble carbonate salt and a complex between the acid and an amine. A water immiscible solvent, such as an alcohol, is added to extract the acid/amine complex from the dilute salt solution to a reaction phase. The reaction phase is continuously dried and a product between the acid and the solvent, such as an ester, is formed.

  8. THIN-LAYER SEPARATION OF CITRIC ACID CYCLE INTERMEDIATES, LACTIC ACID, AND THE AMINO ACID TAURINE

    EPA Science Inventory

    This paper describes a two-dimensional mixed-layer method for separating citric acid cycle intermediates, lactic acid and the amino acid taurine. The method cleanly separates all citric acid cycle intermediates tested, excepting citric acid and isocitric acid. The solvents are in...

  9. Toxicology of Perfluoroalkyl acids

    EPA Science Inventory

    The Perfluoroalkyl acids(PFAAs) area a family of organic chemicals consisting of a perflurinated carbon backbone (4-12in length) and a acidic functional moiety (Carboxylate or sulfonate). These compounds have excellent surface-tension reducing properties and have numerous industr...

  10. Toxicology of Perfluoroalkyl Acids*

    EPA Science Inventory

    The perfluoroalkyl acids (PFAAs) are a family of organic chemicals consisting of a perfluorinated carbon backbone (4-12 in length) and an acidic functional moiety (carboxylate or sulfonate). These compounds are chemically stable, have excellent surface-tension reducing properties...

  11. Lead-acid cell

    SciTech Connect

    Hradcovsky, R.J.; Kozak, O.R.

    1980-12-09

    A lead-acid storage battery is described that has a lead negative electrode, a lead dioxide positive electrode and a sulfuric acid electrolyte having an organic catalyst dissolved therein which prevents dissolution of the electrodes into lead sulfate whereby in the course of discharge, the lead dioxide is reduced to lead oxide and the lead is oxidized.

  12. Proteins and Amino Acids

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Proteins are the most abundant substances in living organisms and cells. All proteins are constructed from the same twenty amino acids that are linked together by covalent bonds. Shorter chains of two or more amino acids can be linked by covalent bonds to form polypeptides. There are twenty amino...

  13. EFFECTS OF ACID PRECIPITATION

    EPA Science Inventory

    Recent reviews of available data indicate that precipitation in a large region of North America is highly acidic when its pH is compared with the expected pH value of 5.65 for pure rain water in equilibrium with CO2. A growing body of evidence suggests that acid rain is responsib...

  14. Bile acid transporters

    PubMed Central

    Dawson, Paul A.; Lan, Tian; Rao, Anuradha

    2009-01-01

    In liver and intestine, transporters play a critical role in maintaining the enterohepatic circulation and bile acid homeostasis. Over the past two decades, there has been significant progress toward identifying the individual membrane transporters and unraveling their complex regulation. In the liver, bile acids are efficiently transported across the sinusoidal membrane by the Na+ taurocholate cotransporting polypeptide with assistance by members of the organic anion transporting polypeptide family. The bile acids are then secreted in an ATP-dependent fashion across the canalicular membrane by the bile salt export pump. Following their movement with bile into the lumen of the small intestine, bile acids are almost quantitatively reclaimed in the ileum by the apical sodium-dependent bile acid transporter. The bile acids are shuttled across the enterocyte to the basolateral membrane and effluxed into the portal circulation by the recently indentified heteromeric organic solute transporter, OSTα-OSTβ. In addition to the hepatocyte and enterocyte, subgroups of these bile acid transporters are expressed by the biliary, renal, and colonic epithelium where they contribute to maintaining bile acid homeostasis and play important cytoprotective roles. This article will review our current understanding of the physiological role and regulation of these important carriers. PMID:19498215

  15. Fats and fatty acids

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The absolute fat requirement of the human species is the amount of essential fatty acids needed to maintain optimal fatty acid composition of all tissues and normal eicosanoid synthesis. At most, this requirement is no more than about 5% of an adequate energy intake. However, fat accounts for appro...

  16. Analysis of Organic Acids.

    ERIC Educational Resources Information Center

    Griswold, John R.; Rauner, Richard A.

    1990-01-01

    Presented are the procedures and a discussion of the results for an experiment in which students select unknown carboxylic acids, determine their melting points, and investigate their solubility behavior in water and ethanol. A table of selected carboxylic acids is included. (CW)

  17. EXPOSURES TO ACIDIC AEROSOLS

    EPA Science Inventory

    Ambient monitoring of acid aerosol in four U.S. cities and in a rural region of southern Ontario clearly show distinct periods of strong acidity. easurements made in Kingston, TN, and Stuebenville, OH, resulted in 24-hr H+ ion concentrations exceeding 100 nmole/m3 more than 10 ti...

  18. Mutant fatty acid desaturase

    DOEpatents

    Shanklin, John; Cahoon, Edgar B.

    2004-02-03

    The present invention relates to a method for producing mutants of a fatty acid desaturase having a substantially increased activity towards fatty acid substrates with chains containing fewer than 18 carbons relative to an unmutagenized precursor desaturase having an 18 carbon atom chain length substrate specificity. The method involves inducing one or more mutations in the nucleic acid sequence encoding the precursor desaturase, transforming the mutated sequence into an unsaturated fatty acid auxotroph cell such as MH13 E. coli, culturing the cells in the absence of supplemental unsaturated fatty acids, thereby selecting for recipient cells which have received and which express a mutant fatty acid desaturase with an elevated specificity for fatty acid substrates having chain lengths of less than 18 carbon atoms. A variety of mutants having 16 or fewer carbon atom chain length substrate specificities are produced by this method. Mutant desaturases produced by this method can be introduced via expression vectors into prokaryotic and eukaryotic cells and can also be used in the production of transgenic plants which may be used to produce specific fatty acid products.

  19. Omega-3 Fatty Acids

    MedlinePlus

    Omega-3 fatty acids are used together with lifestyle changes (diet, weight-loss, exercise) to reduce the amount of triglycerides (a fat-like ... people with very high triglycerides. Omega-3 fatty acids are in a class of medications called antilipemic ...

  20. Salicylic Acid Topical

    MedlinePlus

    Propa pH® Peel-Off Acne Mask ... pimples and skin blemishes in people who have acne. Topical salicylic acid is also used to treat ... medications called keratolytic agents. Topical salicylic acid treats acne by reducing swelling and redness and unplugging blocked ...

  1. Amino Acid Crossword Puzzle

    ERIC Educational Resources Information Center

    Sims, Paul A.

    2011-01-01

    Learning the 20 standard amino acids is an essential component of an introductory course in biochemistry. Later in the course, the students study metabolism and learn about various catabolic and anabolic pathways involving amino acids. Learning new material or concepts often is easier if one can connect the new material to what one already knows;…

  2. Oxidative degradation of different chlorinated phenoxyalkanoic acid herbicides by a hybrid ZrO2 gel-derived catalyst without light irradiation.

    PubMed

    Sannino, Filomena; Pernice, Pasquale; Minieri, Luciana; Camandona, Gaia Aurora; Aronne, Antonio; Pirozzi, Domenico

    2015-01-14

    The oxidative degradation of 2-methyl-4-chlorophenoxyacetic acid (MCPA), 4-(4-chloro-2-methylphenoxy)butanoic acid (MCPB), 4-chlorophenoxyacetic acid (4-CPA) and 2,4-dichlorophenoxyacetic acid (2,4 D) by ZrO2-acetylacetonate hybrid catalyst (HSGZ) without light irradiation was assessed. The thermal stability of the catalyst was investigated by thermogravimetry, differential thermal analysis, and Fourier transform infrared spectroscopy. For each herbicide, a virtually complete removal in about 3 days without light irradiation at room temperature was achieved. The removal kinetics of the herbicides has been satisfactorily characterized by a double-stage physico-mathematical model, in the hypothesis that a first-order adsorption on HSGZ surface is followed by the herbicide degradation, catalytically driven by HSGZ surface groups. The long-term use of the HSGZ catalyst was assessed by repeated-batch tests. The specific cost for unit-volume removal of herbicide was evaluated by a detailed cost analysis showing that it is comparable with those pertaining to alternative methods. PMID:25479367

  3. Trans Fatty Acids

    NASA Astrophysics Data System (ADS)

    Doyle, Ellin

    1997-09-01

    Fats and their various fatty acid components seem to be a perennial concern of nutritionists and persons concerned with healthful diets. Advice on the consumption of saturated, polyunsaturated, monounsaturated, and total fat bombards us from magazines and newspapers. One of the newer players in this field is the group of trans fatty acids found predominantly in partially hydrogenated fats such as margarines and cooking fats. The controversy concerning dietary trans fatty acids was recently addressed in an American Heart Association (AHA) science advisory (1) and in a position paper from the American Society of Clinical Nutrition/American Institute of Nutrition (ASCN/AIN) (2). Both reports emphasize that the best preventive strategy for reducing risk for cardiovascular disease and some types of cancer is a reduction in total and saturated fats in the diet, but a reduction in the intake of trans fatty acids was also recommended. Although the actual health effects of trans fatty acids remain uncertain, experimental evidence indicates that consumption of trans fatty acids adversely affects serum lipid levels. Since elevated levels of serum cholesterol and triacylglycerols are associated with increased risk of cardiovascular disease, it follows that intake of trans fatty acids should be minimized.

  4. Sulfuric Acid on Europa

    NASA Technical Reports Server (NTRS)

    1999-01-01

    Frozen sulfuric acid on Jupiter's moon Europa is depicted in this image produced from data gathered by NASA's Galileo spacecraft. The brightest areas, where the yellow is most intense, represent regions of high frozen sulfuric acid concentration. Sulfuric acid is found in battery acid and in Earth's acid rain.

    This image is based on data gathered by Galileo's near infrared mapping spectrometer.

    Europa's leading hemisphere is toward the bottom right, and there are enhanced concentrations of sulfuric acid in the trailing side of Europa (the upper left side of the image). This is the face of Europa that is struck by sulfur ions coming from Jupiter's innermost moon, Io. The long, narrow features that crisscross Europa also show sulfuric acid that may be from sulfurous material extruded in cracks.

    Galileo, launched in 1989, has been orbiting Jupiter and its moons since December 1995. JPL manages the Galileo mission for NASA's Office of Space Science, Washington DC. JPL is a division of the California Institute of Technology, Pasadena, CA.

  5. Strongly Acidic Auxin Indole-3-Methanesulfonic Acid

    PubMed Central

    Cohen, Jerry D.; Baldi, Bruce G.; Bialek, Krystyna

    1985-01-01

    A radiochemical synthesis is described for [14C]indole-3-methanesulfonic acid (IMS), a strongly acidic auxin analog. Techniques were developed for fractionation and purification of IMS using normal and reverse phase chromatography. In addition, the utility of both Fourier transform infrared spectrometry and fast atom bombardment mass spectrometry for analysis of IMS has been demonstrated. IMS was shown to be an active auxin, stimulating soybean hypocotyl elongation, bean first internode curvature, and ethylene production. IMS uptake by thin sections of soybean hypocotyl was essentially independent of solution pH and, when applied at a 100 micromolar concentration, IMS exhibited a basipetal polarity in its transport in both corn coleoptile and soybean hypocotyl sections. [14C]IMS should, therefore, be a useful compound to study fundamental processes related to the movement of auxins in plant tissues and organelles. PMID:16664007

  6. Understanding acid rain

    SciTech Connect

    Budiansky, S.

    1981-06-01

    The complexities of the phenomenon of acid rain are described. Many factors, including meteorology, geology, chemistry, and biology, all play parts. Varying weather, varying soils, the presence of other pollutants and species differences all act to blur the connections between industrial emissions, acid rain, and environmental damage. Some experts believe that the greatest pH shock to lakes occurs during snow melt and runoff in the spring; others believe that much of the plant damage ascribed to acid rain is actually due to the effects of ozone. Much work needs to be done in the area of sampling. Historical data are lacking and sampling methods are not sufficiently accurate. (JMT)

  7. Hypolipidaemic and antiplatelet activity of phenoxyacetic acid derivatives related to alpha-asarone.

    PubMed

    Pérez-Pastén, Ricardo; García, Rosa Virginia; Garduño, Leticia; Reyes, Elba; Labarrios, Fernando; Tamariz, Joaquín; Chamorro, Germán

    2006-10-01

    The phenoxyacetic acid derivatives 1-6 [2-methoxy-4-(2-propenyl)phenoxyacetic acid (1); 2-methoxy-5-nitro-4-(2-propenyl)phenoxyacetic acid (2); methyl 2-methoxy-4-(2-propenyl)phenoxyacetate (3); ethyl 2-methoxy-4-(2-propenyl)phenoxyacetate (4); methyl 2-methoxy-5-nitro-4-(2-propenyl)phenoxyacetate (5); ethyl 2-methoxy-5-nitro-4-(2-propenyl)phenoxyacetate (6)] related to alpha-asarone have been reported previously as hypolipidaemic agents in diet-induced hyperlipidaemic mice. We have aimed to expand the pharmacological profile of these derivatives by investigating their hypolipidaemic activity in rats and mice under different experimental conditions. The antiplatelet activity was tested also in-vitro from blood derived from consenting healthy volunteers. In normolipidaemic rats, compounds 2, 3 and 5 at oral doses of 40 and 80 mg kg(-1) significantly decreased total cholesterol and LDL-cholesterol levels. Moreover, analogues 3 and 5 administered to hypercholesterolaemic rats at the same doses for seven days also produced a reduction in the content of these same lipoproteins. In neither case were the high-density lipoprotein cholesterol and triglyceride concentrations affected. However, practically all tested compounds were found to be hypocholesterolaemic agents, and were shown to effectively lower low-density lipoprotein cholesterol and triglyceride levels in Triton-induced hyperlipidaemic mice at oral doses of 50 and 100 mg kg(-1). In all tests, all animals appeared to be healthy throughout the experimental period in their therapeutic ranges. Triton-induced hypercholesterolaemic mice appeared to be a desirable model for this class of hypolipidaemic drugs. On the other hand, compounds 1, 2, 4 and 5 significantly inhibited ADP-induced aggregation in-vitro. These findings indicated that all of these compounds appeared to be promising for the treatment of human hyperlipidaemia and thrombotic diseases. PMID:17034657

  8. The earthworm Aporrectodea caliginosa stimulates abundance and activity of phenoxyalkanoic acid herbicide degraders

    PubMed Central

    Liu, Ya-Jun; Zaprasis, Adrienne; Liu, Shuang-Jiang; Drake, Harold L; Horn, Marcus A

    2011-01-01

    2-Methyl-4-chlorophenoxyacetic acid (MCPA) is a widely used phenoxyalkanoic acid (PAA) herbicide. Earthworms represent the dominant macrofauna and enhance microbial activities in many soils. Thus, the effect of the model earthworm Aporrectodea caliginosa (Oligochaeta, Lumbricidae) on microbial MCPA degradation was assessed in soil columns with agricultural soil. MCPA degradation was quicker in soil with earthworms than without earthworms. Quantitative PCR was inhibition-corrected per nucleic acid extract and indicated that copy numbers of tfdA-like and cadA genes (both encoding oxygenases initiating aerobic PAA degradation) in soil with earthworms were up to three and four times higher than without earthworms, respectively. tfdA-like and 16S rRNA gene transcript copy numbers in soil with earthworms were two and six times higher than without earthworms, respectively. Most probable numbers (MPNs) of MCPA degraders approximated 4 × 105 gdw−1 in soil before incubation and in soil treated without earthworms, whereas MPNs of earthworm-treated soils were approximately 150 × higher. The aerobic capacity of soil to degrade MCPA was higher in earthworm-treated soils than in earthworm-untreated soils. Burrow walls and 0–5 cm depth bulk soil displayed higher capacities to degrade MCPA than did soil from 5–10 cm depth bulk soil, expression of tfdA-like genes in burrow walls was five times higher than in bulk soil and MCPA degraders were abundant in burrow walls (MPNs of 5 × 107 gdw−1). The collective data indicate that earthworms stimulate abundance and activity of MCPA degraders endogenous to soil by their burrowing activities and might thus be advantageous for enhancing PAA degradation in soil. PMID:20740027

  9. WASTE ACID DETOXIFICATION AND RECLAMATION

    EPA Science Inventory

    This Environmental Security Technology Certification Program (ESTCP) project demonstrated the Waste Acid Detoxification and Reclamation (WADR) systems ability to recover waste electropolish acid solutions generated during the manufacturing of gun-tubes, and reuse the clean acid. ...

  10. Disorders of Amino Acid Metabolism

    MedlinePlus

    ... Aspiration Syndrome Additional Content Medical News Disorders of Amino Acid Metabolism By Lee M. Sanders, MD, MPH NOTE: ... Metabolic Disorders Disorders of Carbohydrate Metabolism Disorders of Amino Acid Metabolism Disorders of Lipid Metabolism Amino acids are ...

  11. Enzymatic acylation of di- and trisaccharides with fatty acids: choosing the appropriate enzyme, support and solvent.

    PubMed

    Plou, Francisco J; Cruces, M Angeles; Ferrer, Manuel; Fuentes, Gloria; Pastor, Eitel; Bernabé, Manuel; Christensen, Morten; Comelles, Francisco; Parra, José L; Ballesteros, Antonio

    2002-06-13

    Enzymatic synthesis of fatty acid esters of di- and trisaccharides is limited by the fact that most biological catalysts are inactivated by the polar solvents (e.g. dimethylsulfoxide, dimethylformamide) where these carbohydrates are soluble. This article reviews the methodologies developed to overcome this limitation, namely those involving control over the reaction medium, the enzyme and the support. We have proposed the use of mixtures of miscible solvents (e.g. dimethylsulfoxide and 2-methyl-2-butanol) as a general strategy to acylate enzymatically hydrophilic substrates. We observed that decreasing the hydrophobicity of the medium (i.e. lowering the percentage of DMSO) the molar ratio sucrose diesters versus sucrose monoesters can be substantially enhanced. The different regioselectivity exhibited by several lipases and proteases makes feasible to synthesise different positional isomers, whose properties may vary considerably. In particular, the lipase from Thermomyces lanuginosus displays a notable selectivity for only one hydroxyl group in the acylation of sucrose, maltose, leucrose and maltotriose, compared with lipase from Candida antarctica. We have examined three immobilisation methods (adsorption on polypropylene, covalent coupling to Eupergit C, and silica-granulation) for sucrose acylation catalysed by T. lanuginosus lipase. The morphology of the support affected significantly the reaction rate and/or the selectivity of the process. PMID:12142143

  12. Acid soldering flux poisoning

    MedlinePlus

    The harmful substances in soldering fluxes are called hydrocarbons. They include: Ammonium chloride Rosin Hydrochloric acid Zinc ... Lee DC. Hydrocarbons. In: Marx JA, Hockberger RS, Walls RM, et ... Rosen's Emergency Medicine: Concepts and Clinical Practice . 8th ...

  13. Aminolevulinic Acid Topical

    MedlinePlus

    ... in combination with photodynamic therapy (PDT; special blue light) to treat actinic keratoses (small crusty or scaly ... photosensitizing agents. When aminolevulinic acid is activated by light, it damages the cells of actinic keratosis lesions.

  14. Difficult Decisions: Acid Rain.

    ERIC Educational Resources Information Center

    Miller, John A.; Slesnick, Irwin L.

    1989-01-01

    Discusses some of the contributing factors and chemical reactions involved in the production of acid rain, its effects, and political issues pertaining to who should pay for the clean up. Supplies questions for consideration and discussion. (RT)

  15. Uric acid - urine

    MedlinePlus

    ... to filter fluids and waste normally (chronic glomerulonephritis ) Lead poisoning Long-term (chronic) alcohol use Risks There are ... Elsevier Saunders; 2011:chap 28. Read More Gout Lead poisoning Liver disease Polycythemia vera Uric acid - blood Update ...

  16. Amoxicillin and Clavulanic Acid

    MedlinePlus

    ... is used to treat certain infections caused by bacteria, including infections of the ears, lungs, sinus, skin, ... antibiotics. It works by stopping the growth of bacteria. Clavulanic acid is in a class of medications ...

  17. Hydrofluoric acid poisoning

    MedlinePlus

    Chemical Emergencies: Case Definition: Hydrofluoric Acid . Centers for Disease Control and Prevention, U.S. Dept of Health and Human Services; 2005. Goldfrank LR, ed. Goldfrank's Toxicologic Emergencies . 8th ed. New ...

  18. Lead/acid batteries

    NASA Astrophysics Data System (ADS)

    Bullock, Kathryn R.

    Lead/acid batteries are produced in sizes from less than 1 to 3000 Ah for a wide variety of portable, industrial and automotive applications. Designs include Planté, Fauré or pasted, and tubular electrodes. In addition to the traditional designs which are flooded with sulfuric acid, newer 'valve-regulated" designs have the acid immolibized in a silica gel or absorbed in a porous glass separator. Development is ongoing worldwide to increase the specific power, energy and deep discharge cycle life of this commercially successful system to meet the needs of new applications such as electric vehicles, load leveling, and solar energy storage. The operating principles, current status, technical challenges and commercial impact of the lead/acid battery are reviewed.

  19. Citric acid urine test

    MedlinePlus

    ... used to diagnose renal tubular acidosis and evaluate kidney stone disease. ... tubular acidosis and a tendency to form calcium kidney stones. The following may decrease urine citric acid levels: ...

  20. Pantothenic acid and biotin

    MedlinePlus

    ... JavaScript. Pantothenic acid and biotin are types of B vitamins. They are water-soluble, which means that the ... found in foods that are good sources of B vitamins, including the following: Animal proteins Avocado Broccoli, kale, ...