i.e., pyruvic acid, acetoacetic acid, and higher homologs. ... Abstract: ... keto acids, i.e., acetoacetic acid, levulinic acid, etc. ...

Phthalic anhydride was condensed with acetoacetic ester in acetic anhydride and triethylamine solution, and when phthalyl chloride was reacted with sodium acetoacetic ester compounds were formed of the phthalide and indandione series: phthalylacetoacetic ...

The role of ethanol O-d in nullifying the deuterolysis may be demonstrated by determining that transesterification of methyl acetoacetate of the ethyl ester occurs as well as deuterium exchange of the five acetoacetate hydrogens. The significant acidity of the methylene protons in the acetoacetate group, the ...

Absent among (today's) critically important biological compounds reported in carbonaceous meteorites are keto acids, i.e., pyruvic acid, acetoacetic acid, ...

Ketogenesis is usually measured in vivo by dilution of tracers of (3R)-hydroxybutyrate or acetoacetate. We show that, in perfused working rat hearts, the specific activities of (3R)-hydroxybutyrate and acetoacetate are diluted by isotopic exchanges in the absence of net ketogenesis. We call this process pseudoketogenesis. When hearts are perfused with ...

Jul 5, 2007 ... Availability Options > Online [x]; Search Criteria: Search Field: All > Results : All > Search Term: (Acetoacetic Acid Esters) [x] ...

Search Criteria: Search Field: All > Results : All > Search Term: (Acetoacetic Acid Esters) [x]. Sort results by: NASA Center | Date Added to NTRS ...

Selected Navigations: Publication Year > 2001-2010 [x]; Search Criteria: Search Field: All > Results : All > Search Term: (Acetoacetic Acid Esters) [x] ...

A novel approach to the synthesis of purines bearing functionalized carbon substituents or methyl in position 6 was developed. Under different reaction conditions, 6-halopurine derivatives could react with ethyl acetoacetate efficiently to yield 2-(purin-6-yl)acetoacetic acid ethyl esters, (purin-6-yl)acetates and 6-methylpurines ...

To determine the temporal relationship between changes in contractile performance and flux through the citric acid cycle in hearts oxidizing acetoacetate, we perfused isolated working rat hearts with either glucose or acetoacetate (both 5 mM) and freeze-clamped the tissue at defined times. After 60 min of perfusion, hearts utilizing ...

In Clostridium acetobutylicum ATCC 824, acetoacetate decarboxylase (EC 4.1.1.4) is essential for solvent production, catalyzing the decarboxylation of acetoacetate to acetone. We report here the purification of the enzyme from C. acetobutylicum ATCC 824 and the cloning and expression of the gene encoding the acetoacetate decarboxylase ...

In Clostridium acetobutylicum ATCC 824, acetoacetate decarboxylase (EC 4.1.1.4) is essential for solvent production, catalyzing the decarboxylation of acetoacetate to acetone. We report here the purification of the enzyme from C. acetobutylicum ATCC 824 and the cloning and expression of the gene encoding the acetoacetate decarboxylase ...

Normally, the brain's fuel is glucose, but during fasting it increasingly relies on ketones (beta-hydroxybutyrate, acetoacetate, and acetone) produced in liver mitochondria from fatty acid beta-oxidation. Although moderately raised blood ketones produced on a very high fat ketogenic diet have important clinical effects on the brain, including reducing ...

It has been proposed that muscle is the site of net ketogenesis. This hypothesis was based on a discrepancy between the balance of unlabeled and labeled ketone bodies across muscle beds in humans infused with (/sup 14/C)acetoacetate. It has been pointed out that the dilution of the specific activity of acetoacetate could be explained by the reversal of ...

The properties of Raney nickel catalysts modified by (+)-tartaric acid and active in enantioselective hydrogenation of ethyl acetoacetate depend on the chemical and phase compositions of the starting Ni-Al alloys. A decrease of the Ni content in the Ni-Al alloy specimens which corresponds to an increase of the fraction of the NiAl/sub 3/ intermetallic ...

Inhibition of glucose uptake by acetoacetate and relief of this inhibition by insulin found previously in slices of rat mammary gland [Williamson, McKeown & Ilic (1975) Biochem. J. 150. 145-152] was confirmed in acini, which represent a more homogeneous population of cells. Glycerol (1mM) behaved like insulin (50 minuits/ml) in its ability to relieve the inhibition of ...

The formation of various alpha-diazo acetoacetic esters can be obtained in a single transformation with good to excellent yields using readily available 2-diazoacetoacetic acid. PMID:16538259

>Acid dissociation constants of some BETA -keto esters, viz. ethyl acetoacetate, ethyl alpha -phenyl acetoacetate, ethyl alpha - gamma -diphenyl acetoacetate, ethyl alpha -phenyl)phenylpropioloylacetate, ethyl alpha ( alpha -naphthyl)phenylpropioloylacetate, have been determined potentiometrically ...

An automated, one-pot radio-synthesis module for the routine preparation of 1-[(11)C]acetoacetic acid has been developed. The enolate anion of acetone was reacted with [(11)C]CO(2) in tetrahydrofuran (THF), followed by hydrolysis and purification by ion-exchange chromatography. The total synthesis time was 18 min and radiochemical yield was 34% after decay ...

Type-1 diabetic patients experience hyperketonemia caused by an increase in fatty acid metabolism. Thus, the aim of this study was to measure the effect of ketone bodies as suppressors of oxidizing species produced by stimulated neutrophils. Both acetoacetate and 3-hydroxybutyrate have suppressive effect on the respiratory burst measured by ...

New aliphatic polyester-type dendrimers were synthesized using a new AB2-type building block 3, prepared from benzyl acetoacetate and 2 equiv of tert-butyl acrylate by acetoacetic acid ester synthesis. The reiterative [deprotection by HCO2H, then EDCI/DMAP coupling] sequence using divergent growth method gave [G1]-4tBu-[G5]-64tBu ...

A novel enzymatic reaction involved in the metabolism of aliphatic epoxides by Xanthobacter strain Py2 is described. Cell extracts catalyzed the CO2-dependent carboxylation of propylene oxide (epoxypropane) to form acetoacetate and beta-hydroxybutyrate. The time courses of acetoacetate and beta-hydroxybutyrate formaton indicate that ...

We describe an integrated set of experiments for the undergraduate organic laboratory that allows students to compare and contrast biological and chemical means of introducing chirality into a molecule. The racemic reduction of ethyl acetoacetate with sodium borohydride and the same reduction in the presence of a tartaric acid ligand are described, and a ...

Amino groups of amino acids, nucleic acids and lipids can react non-enzymatically with reducing sugars to form unstable Schiff bases that can then undergo the Amadori rearrangement to form irreversible advanced glycation end products (AGEs). Ketoacidosis is a life-threatening complication in patients with untreated diabetes mellitus and it is characterized ...

Formation of wine pyranoanthocyanins in model wine was monitored by HPLC-DAD-ESI-MS/MS, using red grape skin extracts and wine fermentation metabolites (acetaldehyde, pyruvic and acetoacetic acids, and diacetyl) and also hydroxycinnamic acids (p-coumaric, caffeic, ferulic, and sinapic acids). Pyruvic ...

We hypothesized that contrasting leucine with its non-metabolizable analog 2-aminobicyclo[2,2,1]heptane-2-carboxylic acid (BCH) might provide new information about metabolic pathways involved in insulin secretion. Both compounds stimulate insulin secretion by allosterically activating glutamate dehydrogenase, which enhances glutamate metabolism. However, we found that leucine ...

SummaryWe hypothesized that contrasting leucine with its non-metabolizable analog 2-aminobicyclo[2,2,1]heptane-2-carboxylic acid (BCH) might provide new information about metabolic pathways involved in insulin secretion. Both compounds stimulate insulin secretion by allosterically activating glutamate dehydrogenase, which enhances glutamate metabolism. However, we found that ...

The effects of acetoacetic acid, acetone, bilirubin, beta-carotene, three cephalospoprin antibiotics, glucose, hemoglobin and lipid on the kinetic Jaff� reaction and an enzymatic reaction for the determination of creatinine concentration were studied in bovine, canine, feline and equine serum. There were no obvious species' differences. The kinetic ...

Isolated suspensions of colonocytes from the rat were used to assess utilization, interaction, and fate of metabolic substrates normally obtained from colonic bacteria (acetate, propionate, butyrate) or derived from the blood circulation to the colonic mucosa (D-glucose, acetoacetate, L-glutamine). The short-chain fatty acid n-butyrate (10 mM), on its own, ...

Octanoic and decanoic acid, the major constituents of the Medium Chain Triglyceride (MCT) Emulsion diet, have been detected in appreciable quantities in the peripheral blood of children with intractable seizures treated with the MCT diet. Serum concentrations of these acids as well as beta hydroxybutyrate and acetoacetate rose as the ...

1. The synthesis of phosphoenolpyruvate and the O₂ consumption from the tricarboxylic acid-cycle intermediates citrate, ?-oxoglutarate, malate and succinate by guinea-pig mitochondria were compared. Malate was the most effective of these precursors; there was no synthesis of phosphoenolpyruvate from succinate. 2. The addition of palmitate, ...

We have directly tested the ability of acetoacetate, upon activation to the CoA thioester, to channel into the cholesterogenic pathway prior to scrambling of its carbon skeleton with the acetate pool. The approach relies upon trapping [3-13C]acetoacetate-derived hydroxymethylglutaryl-CoA, hydrolyzing this metabolite, and esterifying the resulting ...

A simple method is described for the quantitative analysis of urinary delta-aminolevulinic acid. The 2-methyl-carbethoxy-4-(3-propionic acid) pyrrole, produced by the condensation of delta-aminolevulinic acid with ethyl acetoacetate, is almost completely extracted from an aqueous solution with ethyl acetate without ...

The rate of biosynthesis of ribonucleic acid (as judged by the rate of incorporation of uridine into ribonucleic acid) in infant and adult rat brain cortex slices, incubated aerobically in the presence of various substrates, is directly proportional to the adenosine triphosphate concentration. This suggests that the adenosine triphosphate concentration is ...

Anaplerosis, the net synthesis in mitochondria of citric acid cycle intermediates, and cataplerosis, their export to the cytosol, have been shown to be important for insulin secretion in rodent beta cells. However, human islets may be different. We observed that the enzyme activity, protein level, and relative mRNA level of the key anaplerotic enzyme pyruvate carboxylase (PC) ...

To compare the powers of the corresponding enzymes as catalysts, the rates of uncatalyzed decarboxylation of several aliphatic acids (oxalate, malonate, acetoacetate, and oxaloacetate) were determined at elevated temperatures and extrapolated to 25 �C. In the extreme case of oxalate, the rate of the uncatalyzed reaction at pH 4.2 was 1.1 � 10(-12) ...

Hepatic microsomal enzyme activity was induced in wild-trapped raccoons (Procyon lotor) and selected blood characteristics were measured in an effort to detect responses due to PCB ingestion, nutritional restriction, and their interactions. Barbiturate-induced sleeping times were used as an index of hepatic microsomal activity because they have been used reliably by other workers. Blood ...

Simple methods for the synthesis of 3-aryl-6-methyl-2-pyrones and 3-aryl-5-carbalkoxy-6-methyl-2-pyrones by the reaction of ethyl ..cap alpha..-formylarylacetates with acetone and acetoacetic acid esters, respectively, are proposed. Some electrophilic substitution reactions of 6-methyl-3-phenyl-2-pyrone and 5-carbethoxy-6-methyl-3-phenyl-2-pyrone were ...

It is shown that cerium- molybdenum complex extraction by ketones and ethyl acetoacetate is very weak. The complex does not lend itself to extraction by alcohols, simple or complex ethers, or neutral solutions. Conductometric titration showed that the cerium-molybdenum complex is a strong octabasic acid, as described by the ...

We compared results obtained with the Beckman Creatinine Analyzer (Beckman Instruments, Inc.) to those with the GEMSAEC Centrifugal Analyzer (Electro-Nucleonics, Inc.) and with a manual method for determination of creatinine in serum and urine. Linearity, stability, recovery, and precision were evaluated. Interference from bilirubin, protein, lipemia, uric acid, and hemolysis ...

By 4-nitrophthalic anhydride condensation with acetoacetate in acetic anhydride and triethylamine solution with subsequent breakdown of the intermediate condensation product, 5-nitroindanedione-1,3 was obtained. A 4-nitrophthalic anhydride with acetic anh...

A capillary zone electrophoresis method was optimised to analyse low-molecular-mass organic acids for the purpose of monitoring diabetes in rat plasma. The method included acetoacetic, 2-hydroxybutyric, lactic and uric acids. A variation in the background electrolyte allowed us to measure pyruvic acid in the same ...

Reaction of 4-aminoantipyrine with acetylacetone, ethyl acetoacetate, benzoyl isothiocyanate, phenyl isothiocyanate, maleic anhydride and methoxymethylene Meldrum's acid afforded a series of new antipyrine derivatives. The antibacterial activity of the synthesized compounds against Micrococcus luteus ATCC 9341, Staphilococcus aureus ATCC 29737, and ...

Changes in the metabolism of polyunsaturated fatty acids (PUFA), both in children on the high fat ketogenic diet (KD) for seizure control and in rats on a KD enriched in PUFA, raise the possibility that increased brain arachidonic acid (ARA) and/or docosahexaenoic acid (DHA) may contribute to better seizure control. Our studies with ...

Astrocytes were derived from cortex of two-day-old rat brain and grown in primary culture to confluence. The metabolism of the fatty acids, octanoate and palmitate, to CO{sub 2} in oxidative respiration and to the formation of ketone bodies was examined by radiolabeled tracer methodology. The net production of acetoacetate was also determined by ...

The 1H-13C NMR shifts as well as 1H and 13C coupling constants of 14 alkoxymethylene malonic acid and acetoacetic acid derivatives and two alkoxymethylene acetylacetones are reported. The 17O NMR spectra have been recorded for six of them. The long-range coupling 3J(H-C=C-C(R)) has been used for determining the stereochemistry of the ...

A specific assay for 5-aminolaevulinate synthase activity is described, with a sensitivity comparable with that of radiochemical assays. It is based on measurement by g.l.c. with electron-capture detection of the pentafluorobenzyl ester of the ethyl acetoacetate pyrrole derivative of 5-aminolaevulinic acid, and of the corresponding compound from ...

We developed and validated a sensitive and convenient high-performance liquid chromatography (HPLC) method for the specific determination of ketone bodies (acetoacetate and D-3-hydroxybutyrate) in human plasma. p-Nitrobenzene diazonium fluoroborate (diazo reagent) was used as a precolumn derivatization agent, and 3-(2-hydroxyphenyl) propionic acid was used ...

BackgroundRecent evidence suggests that several human cancers are capable of uncoupling of mitochondrial ATP generation in the presence of intact tricarboxylic acid (TCA) enzymes. The goal of the current study was to test the hypothesis that ketone bodies can inhibit cell growth in aggressive cancers and that expression of uncoupling protein 2 is a contributing factor. The ...

R- and S-(3-/sup 14/C)1,3-butanediol were synthesized by reduction of the corresponding 3-hydroxybutyrates (BHB) with LiAlH/sub 4/. In livers perfused with 5 mM of R- or S-butanediol (BD), the two isomers are taken up at the same rate, about 6 ..mu..mol/g dry wt x min. The uptake of R-BD is matched by an equivalent output of physiological ketone bodies, R-3-hydroxybutyrate and ...

The diagnosis of diabetic ketoacedosis (DKA) may be based upon simple biochemical findings. Measurement of b-hydroxybutyrate in blood may replace semi-quantitative measurement of acetoacetic acid in urine. A list of criteria of graduating severity is suggested for the selection of patients to be treated in intensive care units. During treatment, intensive ...

Conditions to effect the conversion of monosaccharide and disaccharide hydrazones to 1-glycosyl-3-methylpyrazol-5-ones were examined. The sugar pyrazolone derivatives were sensitive to oxidation, but high yields were achieved with 2,2,2-trifluoroethyl acetoacetate in mildly acidic solution. Azo coupling of the pyrazolones produced highly coloured ...

Functionalized diazo acetoacetates are prepared by an efficient Mukaiyama-Michael reaction between methyl 3-(trialkylsilanoxy)-2-diazo-3-butenoate and ?,?-unsaturated enones. Vinyl ether and ketone derivatives are both accessible in good to excellent yield through this methodology. The mild Lewis acid zinc(II) triflate is the optimal catalyst, and it�s ...

Acetoacetate decarboxylase (ADC) (EC4.1.1.4) of Clostridium acetobutylicum DSM 792 was purified to homogeneity, and its first 25 N-terminal amino acids were determined. Oligonucleotide probes deduced from this sequence were used to detect positive clones in partial gene banks derived from Sau3A and HaeIII digests with following ligation into the vector ...

Amiodarone has been shown to produce microvesicular steatosis of the liver in some recipients. We have determined the effects of amiodarone on the mitochondrial oxidation of fatty acids in mice. In vitro, the formation of 14C-acid-soluble beta-oxidation products from (U-14C)palmitic acid by mouse liver mitochondria was decreased by 92% ...

The regulation of ketone-body metabolism and the quantitative importance of ketone bodies as lipid precursors in adult rat brain has been studied in vitro. Utilization of ketone bodies and of pyruvate by homogenates of adult rat brain was measured and the distribution of /sup 14/C from (3-/sup 14/C)ketone bodies among the metabolic products was analysed. The rate of ketone-body utilization was ...

Ketone bodies, D-beta-hydroxybutyrate and acetoacetate, produced by the metabolism of fatty acids, are an important energy source for many organs, especially the heart, kidney and brain. They are utilized by the body with the help of succinyl CoA transferase (SCOT), which is ubiquitously expressed in various organs. Previously, we identified a novel SCOT-t ...

To further investigate pathogenesis and pathogenic process of type 2 diabetes mellitus (T2DM), we compared the urinary metabolic profiling of Zucker obese and Goto-kakizaki (GK) rats by NMR-based metabonomics. Principal component analysis (PCA) on urine samples of both models rats indicates markedly elevated levels of creatine/creatinine, dimethylamine, and acetoacetate, with ...

To compensate for the energetic deficit elicited by reduced carbohydrate intake, mammals convert energy stored in ketone bodies to high energy phosphates. Ketone bodies provide fuel particularly to brain, heart, and skeletal muscle in states that include starvation, adherence to low carbohydrate diets, and the neonatal period. Here, we use novel Oxct1(-/-) mice, which lack the ketolytic enzyme ...

The first one-step, continuous flow synthesis of pyrrole-3-carboxylic acids directly from tert-butyl acetoacetates, amines, and 2-bromoketones is reported. The HBr generated as a byproduct in the Hantzsch reaction was utilized in the flow method to hydrolyze the t-butyl esters in situ to provide the corresponding acids in a single ...

In 28 patients with fulminant hepatic failure alkalaemia was present in 49 of a total of 65 observations. Alkalaemia was due primarlily to a low Pa, C02 in 30 instances and to raised plasma bicarbonate in 16 instances. Blood lactate, pyruvate, and acetoacetate were significantly raised, and in individual cases, blood citrate, succinate, and fumarate were elevated. Blood ...

Simultaneous determination of lactic acid, pyruvic acid, 3-hydroxybutyric acid and acetoacetic acid for clinical monitoring of lactic acidosis and ketone body formation in human plasma (20 microL) was performed by gas chromatography-mass spectrometry in selected ion monitoring (SIM) mode after ...

AtoC has a dual function as both an antizyme, the posttranslational inhibitor of polyamine biosynthetic enzymes, and the transcriptional regulator of genes involved in short-chain fatty acid catabolism (the atoDAEB operon). We have previously shown that AtoC is the response regulator of the AtoS-AtoC two-component signal transduction system that activates atoDAEB when ...

AtoC has a dual function as both an antizyme, the posttranslational inhibitor of polyamine biosynthetic enzymes, and the transcriptional regulator of genes involved in short-chain fatty acid catabolism (the atoDAEB operon). We have previously shown that AtoC is the response regulator of the AtoS-AtoC two-component signal transduction system that activates atoDAEB when ...

OBJECTIVE: The age-related effects of fasting on lipolysis, the production of ketone bodies, and plasma insulin levels were studied in male 3-, 8-, and 32-week-old Sprague-Dawley rats. METHODS: The rats were divided into fasting and control groups. The 3-, 8- and 32-week-old rats tolerated fasting for 2, 5, and 12�days, respectively. RESULTS: Fasting markedly reduced the weights of perirenal and ...

A series of 3,5-dihydroxyheptenoic acid derivatives containing pyrazolopyridine, isoxazolopyridine, thienopyridine, and pyrazolopyrimidine as a key scaffold was synthesized from condensed pyridine and condensed pyrimidine carboxylic acid esters by homologation, aldol condensation with ethyl acetoacetate dianion, and stereoselective ...

The activities of several enzymes of the citric acid and poly-?-hydroxybutyrate cycles were measured in Rhizobium japonicum 3I1B-143 bacteroids which had been isolated from soybean nodules by sucrose gradient centrifugation. During the period of developing nitrogenase activity, the specific activity of fumarase, hydroxybutyrate dehydrogenase, ?-ketothiolase, and pyruvate ...

We report 3 patients with alcoholic ketoacidosis (AKA). All had a history of excessive intake and abrupt termination of alcohol. They showed tachypnea, tachycardia, abdominal tenderness, and epigastralgia. Metabolic acidosis with an increased anion gap, decreased PaCO2 and ketonemia were present. One patient whose ratio of 3-hydroxybutyric acid to ...

11-Chloro-3-methoxy-2-undecenal was synthesized from 8-bromooctanol, and an annelation reaction with this aldehyde and ethyl acetoacetate proceeded to give the ethyl 6-(8-chlorooctyl)salicylate. Ethyl 6-(8-chlorooctyl)salicylate was converted to ethyl 6-(7-formylheptyl)-2-methoxybenzoate through the iodide after protection of the phenolic hydroxyl group. Finally, the Wittig ...

Fatty acid metabolism was investigated in adult male albino rats exposed to hypobaric hypoxia at 25,000 ft simulated altitude for 6 h at 32 degrees C. Oxidation and esterification of palmitic acid-1-14C and de novo lipogenesis from acetate-1-14C were studied. Palmitic acid-1-14C oxidation in liver slices was normal while ...

L(+)Lactic acid enhances myosin ATPase in vitro. Different organic acids were tested for activation of myosin ATPase activity. L(+)Lactic is more effective in stimulating ATPase than D(-)Lactic. D(+) and L(-)Malic acids were also effective at the concentration of 2.5 x 10(-2)-5.0 x 10(-2) mmoles/l. At 3.0 x 10(-2) mmoles/l ...

A synthetic pathway consisting of octAB encoding succinyl-CoA:acetoacetate CoA-transferase and phaA encoding beta-ketothiolase from Ralstonia eutropha H16 was constructed in Escherichia coli for extracellular production of acetoacetate. The recombinant E. coli produced 8.2g/l acetoacetate in shake flasks at 37 degrees C in 24h. In a ...

Upon exposure to visible light, uranyl citrate complex showed photodegradation of citric acid to acetic acid and carbon dioxide, with the precipitation of uranium as uranium trioxide (UO[sub 3][center dot]2H[sub 2]O). The initial pH and presence of oxygen affected the rate and extent of photochemical degradation of the complex, the formation of ...

The capacity of foetal and neonatal liver to oxidize short-, medium- and long-chain fatty acids was studied in the guinea pig. Liver mitochondria from foetal and newborn animals were unable to synthesize ketone bodies from octanoate, but octanoylcarnitine and palmitoylcarnitine were readily ketogenic. The ketogenic capacity at 24 h after birth was as high as in adult animals. ...

The Manila clam (Ruditapes philippinarum) has been considered a good sentinel species for metal pollution monitoring in estuarine tidal flats. Along the Bohai coast of China, there are dominantly distributed three species of clams (White, Liangdao Red and Zebra in Yantai population) endowed with distinct tolerances to environmental stressors. In this study, adductor muscle samples were collected ...

HMGCS2 (hydroxymethylglutaryl CoA synthase 2), the gene that regulates ketone body production, is barely expressed in cultured cell lines. In this study, we restored HMGCS2 expression and activity in HepG2 cells, thus showing that the wild type enzyme can induce fatty acid ?-oxidation (FAO) and ketogenesis, whereas a catalytically inactive mutant C166A did not generate either ...

Solvent synthesis in Clostridium acetobutylicum is induced in concert with sporulation to counteract the dangerous effects of produced butyric and acetic acids and to provide the cell with sufficient time to complete endospore formation. Cardinal transcription units for butanol and acetone production are the sol and adc operons encoding butyraldehyde/butanol dehydrogenase and ...

1-hydrazino-3-thioxo-5,6,7,8-tetrahydroisoquinoline-4-carbonitrile (3) was subjected to react with bifunctional compounds namely: acetylacetone, ethyl cyanoacetate, ethyl benzoylactate, diethylmalonate and ethyl acetoacetate to produce pyrazololthienotetrahydroisoquinoline derivatives 6-11. Also, heating of compound (3) with formic acid afforded ...

The review deals with the present state of the chemistry of organophosphorus compounds with an active methylene group: esters and nitriles of phosphonoacetic acids, phosphonoacetone, and other compounds in which the methylene group is linked directly to the P=O and any other electronegative group. Compounds of this type are analogues of acetoacetic, ...

A multi-centre evaluation of the test strip analyser, Rapimat, was performed by four laboratories following the ECCLS 2nd draft guidelines for the evaluation of analysers in clinical chemistry. Using the Rapignost urine test strip with the test fields for bilirubin, urobilinogen, acetoacetate, ascorbic acid, glucose, protein, nitrite, pH and haemoglobin, ...

Nickel dispersed on wide-pore silica has been used as catalyst in a study of the reaction kinetics of the hydrogenation of methyl-acetoacetate (MAA). The hydrogenation in the gas phase with a H/sub 2//MAA ratio of approx. 10/sup 3/ is found to be limited by the catalytic reaction proper if the rate is kept low, but tends to become limited by pore diffusion of MAA when higher ...

A simple and highly sensitive reagent of salicylaldehyde 3-oxobutanoylhydrazone (salicylaldehyde acetoacetic acid hydrazone, SAAH) was synthesized and studied for the spectrophotometric determination of nickel in detail. In the pH range 6, which greatly increased the selectivity, nickel reacted with SAAH to form a 1:1 yellow complex, having a sensitive ...

The catalytic (hydrogenation of propylene), asymmetric (enantioselective hydrogenation of ethyl acetoacetate), and magnetic properties of intermetallic compounds with the composition Ln(NiM)/sub 5/(IMC), where Ln = La, Sm, Gd; M = Ti, V, Cr, Mn, Cu, and of their hydrides have been studied. The data obtained indicate that the catalytic activity of the above compounds in both ...

Mitochondrial acetoacetyl-CoA thiolase deficiency (or beta-ketothiolase deficiency) is a rare metabolic disorder characterized by acute episodes of severe acidosis and ketosis. A case is presented of an 18-month-old boy who presented with vomiting and diarrhoea and was found to be markedly acidotic. When the acidosis persisted despite saline fluid boluses and bicarbonate correction, further ...

The reaction of ethyl acetoacetate with meta-cresol in an acidic ionic liquid yielded a complex mixture of condensation products. 4,7-Dimethyl�coumarin and the title compound, C₂₀H₂₂O₃, were isolated. The title compound shows chemical but not crystallographic mirror symmetry. The two ...

Diabetes mellitus is a complex metabolic disorder characterized by chronic hyperglycemia, hypoinsulinemia, and ketosis. To access the biochemical process of diabetes, we applied quantitative (1)H NMR-based metabonomics to analyze urine, serum, and liver extracts from streptozotocin-induced diabetic rats. Principle component analysis (PCA) of (1)H NMR spectra disclosed metabolic pattern differences ...

CONTENTS I. Introduction 27 II. 3-Chlorobut-2-enol and its ethers 28 III. 3-Chlorobut-2-enyl esters of carboxylic acids 28 IV. Condensation with aromatic hydrocarbons and related reactions 29 V. Reactions with organometallic compounds 29 VI. Syntheses based on the products of condensation of 1,3-dichlorobut-2-ene with malonic and acetoacetic esters 30 VII. ...

The attempt to prepare toluene-2 C-14 starting from ethyl acetoacetate failed because the reaction of sodium ethyl acetoacetate with dibromopropane could not be performed. This labelling was also attempted starting from methyl tetrahydropyran. This synthe...

The reactions of picrylacetoacetic ester and picrylacetone with bases (alcoholates, amines, phosphine imine compounds) lead to deprotonation of the carbonyl part of the molecule. With the acetoacetic ester anion trinitrobenzene forms a stable 1:1 sigma complex at the ..cap alpha..-carbon atom.

A commercially available immobilized preparation of Rhizomucor miehei lipase (Lipozyme RMIM) has been employed in the synthesis of partial glycerides of acetoacetate. Due to the chemical reactivitity of the acetoacetyl group, these glycerides could have novel uses in e.g. polymer formation. Both 1...

(Z)-2-(2-formamido-4-thiazolyl)-2-(substituted alkoxyimino) acetic acids were synthesized by a new method based on the following sequence of reactions: treatment of the tert-butyl acetoacetate with sodium nitrite, alkylation of the oxime formed with an appropriate alkyl halide, halogenation of methyl alpha-keto group and simultaneous cleavage of tert-butyl ...

Novel unusual microbial dehalogenation during enantioselective reduction of ethyl 4,4,4-trifluoro acetoacetate with baker�s yeast