Sample records for santonin

  1. Stereoselective Synthesis of 8,12-Furanoeudesmanes from Santonin. Absolute Stereochemistry of Natural Furanoeudesma-1,3-diene and Tubipofurane.

    PubMed

    Blay, Gonzalo; Cardona, Luz; García, Begoña; Pedro, José R.; Sánchez, Juan J.

    1996-05-31

    Ketobutenolide 3, easily obtained from santonin (1), has been transformed into two natural furanoeudesmanes 4 and 5, isolated from Commiphora molmol and Tubipora musica, respectively. trans- And cis-decalin systems were obtained by stereoselective reduction of the C(4)-C(5) double bond in 3 in the following way: hydrogenation of 3 over Pd/C followed by acidic treatment gave the cis isomer 10 as the major product; selective hydrogenation of the C(1)-C(2) double bond with the Wilkinson's catalyst followed by reduction with NaTeH yielded mainly the trans isomer 9. Compounds 9 and 10 were transformed into 4 and 5 in parallel sequences. Optical rotation and CD measurements of the synthetic products revealed that the stereochemistry of both natural products should be revised to their enantiomeric form.

  2. Measurement of residual chemical shift anisotropies in compressed polymethylmethacrylate gels. Automatic compensation of gel isotropic shift contribution.

    PubMed

    Hallwass, Fernando; Teles, Rubens R; Hellemann, Erich; Griesinger, Christian; Gil, Roberto R; Navarro-Vázquez, Armando

    2018-05-01

    Mechanical compression of polymer gels provides a simple way for the measurement of residual chemical shift anisotropies, which then can be employed, on its own, or in combination with residual dipolar couplings, for structural elucidation purposes. Residual chemical shift anisotropies measured using compression devices needed a posteriori correction to account for the increase of the polymer to solvent ratio inside the swollen gel. This correction has been cast before in terms of a single-free parameter which, as shown here, can be simultaneously optimized along with the components of the alignment tensor while still retaining discriminating power of the different relative configurations as illustrated in the stereochemical analysis of α-santonin and 10-epi-8-deoxycumambrin B. Copyright © 2018 John Wiley & Sons, Ltd.

  3. Facile preparation of bioactive seco-guaianolides and guaianolides from Artemisia gorgonum and evaluation of their phytotoxicity.

    PubMed

    Macías, Francisco A; Santana, Alejandro; Yamahata, Azusa; Varela, Rosa M; Fronczek, Frank R; Molinillo, José M G

    2012-11-26

    Commercially available santonin was used to synthesize seven sesquiterpene lactones using a facile strategy that involved a high-yielding photochemical reaction. Three natural products from Artemisia gorgonum were synthesized in good yields, and in the case of two compounds, absolute configurations were determined from X-ray quality crystals. The structures previously reported for these compounds were revised. Sesquiterpene lactones were tested using the etiolated wheat coleoptile bioassay, and the most active compounds were assayed in standard target species. seco-Guaianolide (4) showed higher phytotoxic activities than the known herbicide Logran. This high activity could be due to the presence of a cyclopentenedione ring. These results suggest that compound 4 should be involved in defense of A. gorgorum, displaying a wide range of activities that allow proposing them as new leads for development of a natural herbicide model with a seco-guaianolide skeleton.

  4. Complexation of sesquiterpene lactones with cyclodextrins: synthesis and effects on their activities on parasitic weeds.

    PubMed

    Cala, Antonio; Molinillo, José M G; Fernández-Aparicio, Mónica; Ayuso, Jesús; Álvarez, José A; Rubiales, Diego; Macías, Francisco A

    2017-08-09

    Allelochemicals are safer, more selective and more active alternatives than synthetic agrochemicals for weed control. However, the low solubility of these compounds in aqueous media limits their use as agrochemicals. Herein, we propose the application of α-, β- and γ-cyclodextrins to improve the physicochemical properties and biological activities of three sesquiterpene lactones: dehydrocostuslactone, costunolide and (-)-α-santonin. Complexation was achieved by kneading and coprecipitation methods. Aqueous solubility was increased in the range 100-4600% and the solubility-phase diagrams suggested that complex formation had been successful. The results of the PM3 semiempirical calculations were consistent with the experimental results. The activities on etiolated wheat coleoptiles, Standard Target Species and parasitic weeds were improved. Cyclodextrins preserved or enhanced the activity of the three sesquiterpene lactones. Free cyclodextrins did not show significant activity and therefore the enhancement in activity was due to complexation. These results are promising for applications in agrochemical design.

  5. Permeation of bioactive constituents from Arnica montana preparations through human skin in-vitro.

    PubMed

    Tekko, I A; Bonner, M C; Bowen, R D; Williams, A C

    2006-09-01

    This study investigated and characterised transdermal permeation of bioactive agents from a topically applied Arnica montana tincture. Permeation experiments conducted over 48 h used polydimethylsiloxane (silastic) and human epidermal membranes mounted in Franz-type diffusion cells with a methanol-water (50:50 v/v) receptor fluid. A commercially available tincture of A. montana L. derived from dried Spanish flower heads was a donor solution. Further donor solutions prepared from this stock tincture concentrated the tincture constituents 1, 2 and 10 fold and its sesquiterpene lactones 10 fold. Permeants were assayed using a high-performance liquid chromatography method. Five components permeated through silastic membranes providing peaks with relative retention factors to an internal standard (santonin) of 0.28, 1.18, 1.45, 1.98 and 2.76, respectively. No permeant was detected within 12 h of applying the Arnica tincture onto human epidermal membranes. However, after 12 h, the first two of these components were detected. These were shown by Zimmermann reagent reaction to be sesquiterpene lactones and liquid chromatography/diode array detection/mass spectrometry indicated that these two permeants were 11,13-dihydrohelenalin (DH) analogues (methacrylate and tiglate esters). The same two components were also detected within 3 h of topical application of the 10-fold concentrated tincture and the concentrated sesquiterpene lactone extract.

  6. Identification of three novel natural product compounds that activate PXR and CAR and inhibit inflammation

    PubMed Central

    Kittayaruksakul, Suticha; Zhao, Wenchen; Xu, Meishu; Ren, Songrong; Lu, Jing; Wang, Ju; Downes, Michael; Evans, Ronald M.; Venkataramanan, Raman; Chatsudthipong, Varanuj; Xie, Wen

    2013-01-01

    The pregnane X receptor (PXR) and constitutive androstane receptor (CAR) have been known to play a role in xenobiotic metabolism by regulating the expression of drug-metabolizing enzymes and transporters. In addition, PXR agonists were found to exert therapeutic effects through multiple mechanisms, such as detoxification of bile acids and inhibition of inflammation. In this study, we first investigated the effects of three natural product compounds, carapin, santonin and isokobusone, on the activity of PXR and CAR. These compounds activated both PXR and CAR in transient transfection and luciferase reporter gene assays. Mutagenesis studies showed that two amino acid residues, Phe305 of the rodent PXR and Leu308 of the human PXR, are critical for the recognition of these compounds by PXR. Importantly, the activation of PXR and CAR by these compounds induced the expression of drug-metabolizing enzymes in primary human and mouse hepatocytes. Furthermore, activation of PXR by these compounds inhibited the expression of inflammatory mediators in response to lipopolysaccharide (LPS). The effects of these natural compounds on drug metabolism and inflammation were abolished in PXR−/− hepatocytes. These natural compounds can be explored for their potential in the treatment of diseases where the PXR activation has been shown to be beneficial, such as inflammatory bowel disease, cholestasis, and hyperbilirubinemia. PMID:23896737

  7. [About flavouring substances and flavouring preparations regulation in the field of manufacturing of flavourings and foodstuffs].

    PubMed

    Bagriantseva, O V; Shatrov, G N

    2013-01-01

    In article are given substantiation for modification of contemporary list of biologically active substances with undesirable toxicological qualities (namely included in this list of menthofuran, methyleugenol (4-Allyl-1,2-dimethoxybenzene), teucrin A, capsaicin, estragol1 (-Allyl-4-methoxybenzene) and excluded from the list of quinine, santonin, berberin) and developing the list of plants--natural sources of flavourings substances. The new criteria of European Union for including into the relevant for using in/on foodstuff list of flavouring substances, which was published in the Comission Implementing Regulation (EU) No 872/2012 concerning flavourings, listed the 11 flavouring substances for which have been established indexes of foodstuffs in manufacturing, which there are could using and criteria of their safety (caffeine, theobromine, neohesperidin dihydrocalcone, rebaudioside A, d-camphor, three quinine salts (FL 14.011, FL 14.152 and FL 14.155), glycyrrhizic acid and its ammoniated form, ammonium chloride, discussed the possibility of using R- and S-isomers of flavouring substances and L- and D-forms of aminoacids for preparing of flavours, are discussed. Improving of the system of safety using of flavourings in Russian Federation, harmonized with demands of European Union and FAQ/WHO, are, at first, connected with the necessity of reevaluation of the list flavouring substances, which could be use in/on foodstuff, developing of list of the plants--natural sources of flavourings substances and preparations and regulations of using flavourings preparations which can include biologically active substances.

  8. Isolation and Identification of Compounds from Bioactive Extracts of Taraxacum officinale Weber ex F. H. Wigg. (Dandelion) as a Potential Source of Antibacterial Agents

    PubMed Central

    Espinoza, Luis; Madrid, Alejandro; Pizarro, Leonardo

    2018-01-01

    Currently, the most effective treatment for recurrent urinary tract infections in women is antibiotics. However, the limitation for this treatment is the duration and dosage of antibiotics and the resistance that bacteria develop after a long period of administration. With the aim of identifying mainly novel natural agents with antibacterial activity, the present study was undertaken to investigate the biological and phytochemical properties of extracts from the leaves Taraxacum officinale. The structural identification of compounds present in hexane (Hex) and ethyl acetate (AcOEt) extracts was performed by mass spectrometry (GC-MS) spectroscopic techniques and nuclear magnetic resonance (NMR) with the major compounds corresponding to different sesquiterpene lactones (α-santonin, glabellin, arborescin, and estafiatin), monoterpene (9,10-dimethyltricycle [4.2.1.1 (2,5)]decane-9,10-diol), phytosterol (Stigmasta-5,22-dien-3β-ol acetate), terpenes (lupeol acetate, pregn-5-en-20-one-3β-acetyloxy-17-hydroxy, 2-hydroxy-4-methoxy benzaldehyde), and coumarin (benzofuranone 5,6,7,7-a-tetraaldehyde-4,4,7a-trimethyl). The results obtained show that the Hex extract was highly active against Staphylococcus aureus showing a MIC of 200 μg/mL and moderately active against Escherichia coli and Klebsiella pneumoniae with MIC values of 400 μg/mL and 800 μg/mL for the other Gram-negative strains tested with Proteus mirabilis as uropathogens in vitro. Therefore, the effective dandelion extracts could be used in the development of future products with industrial application. PMID:29507587

  9. Isolation and Identification of Compounds from Bioactive Extracts of Taraxacum officinale Weber ex F. H. Wigg. (Dandelion) as a Potential Source of Antibacterial Agents.

    PubMed

    Díaz, Katy; Espinoza, Luis; Madrid, Alejandro; Pizarro, Leonardo; Chamy, Rolando

    2018-01-01

    Currently, the most effective treatment for recurrent urinary tract infections in women is antibiotics. However, the limitation for this treatment is the duration and dosage of antibiotics and the resistance that bacteria develop after a long period of administration. With the aim of identifying mainly novel natural agents with antibacterial activity, the present study was undertaken to investigate the biological and phytochemical properties of extracts from the leaves Taraxacum officinale. The structural identification of compounds present in hexane (Hex) and ethyl acetate (AcOEt) extracts was performed by mass spectrometry (GC-MS) spectroscopic techniques and nuclear magnetic resonance (NMR) with the major compounds corresponding to different sesquiterpene lactones ( α -santonin, glabellin, arborescin, and estafiatin), monoterpene (9,10-dimethyltricycle [4.2.1.1 (2,5)]decane-9,10-diol), phytosterol (Stigmasta-5,22-dien-3 β -ol acetate), terpenes (lupeol acetate, pregn-5-en-20-one-3 β -acetyloxy-17-hydroxy, 2-hydroxy-4-methoxy benzaldehyde), and coumarin (benzofuranone 5,6,7,7-a-tetraaldehyde-4,4,7a-trimethyl). The results obtained show that the Hex extract was highly active against Staphylococcus aureus showing a MIC of 200  μ g/mL and moderately active against Escherichia coli and Klebsiella pneumoniae with MIC values of 400  μ g/mL and 800  μ g/mL for the other Gram-negative strains tested with Proteus mirabilis as uropathogens in vitro . Therefore, the effective dandelion extracts could be used in the development of future products with industrial application.

  10. Extraction, fractionation and re-fractionation of Artemisia nilagirica for anticancer activity and HPLC-ESI-QTOF-MS/MS determination.

    PubMed

    Sahu, Neha; Meena, Sanjeev; Shukla, Vijaya; Chaturvedi, Priyank; Kumar, Brijesh; Datta, Dipak; Arya, K R

    2018-03-01

    Medicinal plants used in traditional medicines are affordable, easily accessible, safer, less toxic and considered as a rich or efficient source of bioactive molecules for modern therapeutics. Artemisia nilagirica (AR) has a long history of use in Indian traditional medicine to combat a wide variety of diseases including cancer. Considering the vast potential of traditional healing plants to deliver safer, less toxic and efficient chemotherapeutics, we have examined anticancer activity of ethanolic extract, bioactive fractions and sub-fractions of AR against different human cancer cell lines along with their phytochemical analysis to understand the insights of novel anticancer activities for further preclinical studies. Fresh plant material of AR was procured from the wild, dried and ground. The grinded materials was extracted in ethanol (AR-01) and fractionated into butanol (AR-02), ethyl acetate (AR-03), hexane (AR-04) and water (AR-05). The cytotoxicity was evaluated against three different human cancer cell lines, i.e. colon (DLD-1), lung (A-549), and breast (MCF-7) using Sulforhodamine B (SRB) assay along with non-cancerous VERO cells as control and doxorubicin (DOX) as positive control. As we observed strong cytotoxicity of AR-03 and AR-04 fractions against tested cells and marked cytotoxic effects particularly in colon cancer cell lines, we further re-fractionated, AR-03 into (AR-03A, AR-03B, AR-03C, AR-03D, AR-03E) and AR-04 into (AR-04A, AR-04B, AR-04C) sub-fractions by column chromatography and investigated against the same panel of cell lines in addition to one more colon cancer cell line (HT-29). Phytochemical analysis was performed through HPLC-ESI-QTOF-MS/MS fragmentation. Ethyl acetate (AR-03) and hexane (AR-04) fractions were found to be the most cytotoxic against all the tested cell lines. Further, AR-03E and AR-04A sub-fractions were found more specific cytotoxic selectively against DLD-1 cancer cell lines at 100µg/ml concentration. HPLC-ESI-QTOF-MS/MS determination revealed the presence of 17 compounds in AR-01. Among them, 4 compounds were reported for the first time in this species. However, 3 identified compounds (artemorin, β-santonin and caryophyllene oxide) in AR-03E sub-fraction were commonly present in each bioactive fraction and may be considered as potential and safest cytotoxic agents for anticancer activity. Experimental evidences reported in this paper for anticancer activity validate the traditional wisdom of Artemisia nilagirica as an anticancer herbal drug. To our knowledge, this is our first novel observation of cytotoxicity and selectivity of ethyl acetate and hexane sub-fraction of AR-01 i.e. AR-03E and AR-04A respectively against DLD-1 human cancer cell lines. HPLC-ESI-QTOF-MS/MS determination attributes the identification of cytotoxic compounds which may be used for further preclinical studies. Copyright © 2017 Elsevier B.V. All rights reserved.

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