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Dai Sig Im Chan Seong Cheong So Ha Lee 《Journal of Molecular Catalysis .B, Enzymatic》2003,26(3-6):131-143
Enzymatic resolution of tertiary arylic nitrile alcohols (1–8) by lipases from Pseudomonas cepacia (PCL), Pseudomonas flurescens (LAK, made by Amano Enzyme Co. Ltd.), Pseudomonas fluorescens (PFL) and Candida rugosa (CRL) were described, and the absolute configuration of the resolved chiral alcohols (1–8) were determined by chemical transformations to the compounds with known configuration. 相似文献
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Biocatalytic synthesis of enantiomerically pure compounds for pharmaceutical intermediates is gaining momentum. This is the result of advances in genomics, screening and evolution technologies leading to the increased availability of new and robust biocatalysts suited for industrial-scale application, and is stimulated by an increased demand for catalysts that are able to address the increased complexity of active pharmaceutical ingredients. The vast majority of biotransformation reactions for the manufacturing of optically active pharmaceutical intermediates are still based on enantioselective ketone reductions and enantiospecific hydrolyses. This review aims to point at alternative reaction types and integrated multi-enzymatic steps that are emerging in large-scale applications. 相似文献
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《Biocatalysis and Biotransformation》2013,31(2):125-131
AbstractHigh yield and selectivity in the intramolecular synthesis of the macrocyclic lactone oxacyclohexadecan-2-one were achieved via a straightforward biocatalytic synthesis utilising non-conventional solvents: supercritical carbon dioxide (scCO2), ethane, fluoroform and 1,1,1,2-tetrafluoroethane. Batch and continuous syntheses were demonstrated with a higher yield attained in a continuous synthesis using in-situ product extraction by scCO2. A remarkably high yield was obtained in 1,1,1,2-tetrafluoroethane at batch conditions. 相似文献
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The enantiomeric purities of optically active intermediates for β-adrenergic blocking agents prepared via enzyme-assisted processes can be determined rapidly and with high accuracy using HPLC on commercially available columns with chiral supports [Chiralcel OD, OB; Chiralpak OT(+)]. The dependence of the resolution parameters on the substitution pattern of both hydroxy compounds and their esters is reported. © 1993 Wiley-Liss, Inc. 相似文献
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M. A. P. J. Hacking F. van Rantwijk R. A. Sheldon 《Journal of Molecular Catalysis .B, Enzymatic》2000,9(4-6):183-191
The acylation of hydrazine, to afford the N,N′-diacyl derivatives, was catalysed by a number of lipases. The rates of the first and second steps depended on the lipase and the type of solvent used. Water, up to 0.4 M, had no detrimental effect on the yield and complete conversion to the N,N′-diacyl derivative was accomplished with some lipases. The hydrazide of 2-(4-isobutylphenyl)propanoic acid (ibuprofen), prepared by non-enzymatic reaction of ibuprofen methyl ester with hydrazine, acted as a nucleophile towards several lipases that do not accept ibuprofen derivatives as the acyl donor, but the enantiomer differentiation was inefficient in most cases. The best result was obtained with Pseudomonas lipoprotein lipase on EP 100 which formed the (R) enantiomer of the product (N-octanoyl-N′-2-(4-isobutylphenyl)propanoylhydrazine) with an enantiomeric ratio E of 26. 相似文献
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Patel RN 《Current opinion in biotechnology》2001,12(6):587-604
There has been an increasing awareness of the enormous potential of microorganisms and enzymes for the transformation of synthetic chemicals with high chemo-, regio- and enantioselectivity. Chiral intermediates and fine chemicals are in high demand, both from the pharmaceutical and agrochemical industries, for the preparation of bulk drug substances and agricultural products. Biocatalytic processes have been described for the synthesis of chiral intermediates for beta3- and beta2-receptor agonists, antihypertensive drugs, antiviral agents, melatonin receptor agonists, anticholesterol and anticancer drugs, and drugs to treat Alzheimer's disease. 相似文献
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Patel RN 《Biomolecular engineering》2001,17(6):167-182
Biocatalytic processes were used to prepare chiral intermediates required for the synthesis of Omapatrilat 1 by three different routes. The synthesis and enzymatic conversion of 2-keto-6-hydroxyhexanoic acid 3 to L-6-hydroxynorleucine 2 was demonstrated by reductive amination using beef liver glutamate dehydrogenase. To avoid the lengthy chemical synthesis of the ketoacid 3, a second route was developed to prepare the ketoacid by treatment of racemic 6-hydroxy norleucine [readily available from hydrolysis of 5-(4-hydroxybutyl) hydantoin 4] with D-amino acid oxidase from porcine kidney or Trigonopsis variabilis followed by reductive amination to convert the mixture completely to L-6-hydroxynorleucine in 98% yield and 99% enantiomeric excess (e.e.). The enzymatic synthesis of (S)-2-amino-5-(1,3-dioxolan-2-yl)-pentanoic acid (allysine ethylene acetal, 5) was demonstrated using phenylalanine dehydrogenase (PDH) from T. intermedius. Phenylalanine dehydrogenase was cloned and overexpressed in Escherichia coli and Pichia pastoris. Using PDH from E. coli or P. pastoris, the enzymatic process was scale-up to prepare kg quantity of allysine ethylene acetal 5. The reaction yields of >94% and e.e. of >98% were obtained for allysine ethylene acetal 5. An enzymatic process was developed for the synthesis of [4S-(4a,7a,10ab)]1-octahydro-5-oxo-4 [[(phenylmethoxy)carbonyl]amino]-7H-pyrido-[2,1-b] [1,3]thiazepine-7-carboxylic acid [BMS-199541-01]. The enzymatic oxidation of the epsilon-amino group of lysine in the dipeptide dimer N(2)-[N[[(phenyl-methoxy)carbonyl] L-homocysteinyl] L-lysine)-1,1-disulphide [BMS-201391-01] to produce BMS-199541-01 using a novel L-lysine epsilon-aminotransferase (LAT) from Sphingomonas paucimobilis SC 16113 was demonstrated. This enzyme was overexpressed in E. coli and a process was developed using the recombinant enzyme. 相似文献
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有机相中脂肪酶催化不对称酯合成反应动力学的研究杨红,高修功,郭妮妮,曹淑桂,杨同书(吉林大学酶工程国家重点实验室,长春130023)在环已烷中应用酵母脂肪酶催化外消旋2-辛醇和辛酸的不对称酯合成反应,研究了该反应的动力学机制,测定了表现动力学常数.利... 相似文献
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微环境对脂肪酶催化拆分外消旋2-辛醇的影响 杨红,曹淑桂,韩四平,黄仲丽,杨同书(吉林大学酶工程国家重点实验室,长春130023)手性2-辛醇不仅是制备液晶材料不可缺少的重要手性原料,也是合成具有光学活性的医药和农药的重要手性中间体.本文... 相似文献
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We have screened a new enzyme for the resolution ofR, S-naproxen enantiomers. The enzyme is free of lipase activity, and possesses a very high stereo-specificity on S-naproxen [2-(6-methoxy-2-naphthyl)-propionic acid] esters and esters of related drugs. The primary structure of the enzyme, determined from the nucleotide sequence, shows limited homology with the catalytic site of lipases. The gene coding for the stereo-selective carboxylesterase has been cloned and expressed inBacillus subtilis. Using a multicopy vector and an additional strong promoter an efficient production process was developed.The enzyme was shown to be sensitive to very high concentrations of the products formed during the reaction it catalyses. To increase the resistance of the enzyme, lysine residues thought to be responsible for this phenomenon were replaced through site-directed mutagenesis. Enzymes with improved stability were obtained. An explanation is given in terms of a model in which a reaction of the acid moiety of naproxen with free lysine NH2 groups is a major cause of inactivation. 相似文献
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Mikio Fujii Sadayuki Ishii Ryota Saito Hiroyuki Akita 《Journal of Molecular Catalysis .B, Enzymatic》2009,59(4):254-260
The optical resolution of racemic albicanol (rac-1) based on the lipase-catalyzed transesterification by using vinyl myristate as an acyl donor afforded (8aR)-1 (99% ee) in 43% yield and (8aS)-1 (99% ee) in 37%. E value of the enzymatic reaction was 56.7 which was superior to that of the reported value (E = 25) by using isopropenyl acetate as an acyl donor. As the synthetic application of obtained (8aR)-1, (−)-copalic acid ((8aR)-3) and (−)-copalol ((8aR)-4) were synthesized from (8aR)-1 in 35% and 34% total yield, respectively. 相似文献
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Enzymatic synthesis of derivatives of vitamin A in organic media 总被引:3,自引:0,他引:3
Thierry Maugard Marie Dominique Legoy 《Journal of Molecular Catalysis .B, Enzymatic》2000,8(4-6):275-280
The present article provides an enzymatic method of retinol esterification to reduce photodestruction and irritation problems characteristic of retinol. More specifically, it relates to a method of synthesising retinyl adipate, retinyl succinate, retinyl oleate and retinyl lactate greatly appreciated by cosmetic manufacturer. Desired compounds can be synthesised directly using Candida antarctica lipase and Rhizomucor miehei lipase in organic media. 相似文献
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Roland Wohlgemuth Dr. 《Biotechnology journal》2009,4(9):1253-1265
Metabolic networks have been an interesting starting point not only for the design of synthetic routes in a similar sequence of reactions, e.g., in biomimetic syntheses, but also for assembling a number of biocatalytic steps by preparing the required enzymes and auxiliary reagents. Retrosynthetic analysis involving multiple biocatalytic reactions steps therefore needs to consider the practically realized biocatalytic single steps. The opportunities for route selection are enlarged if novel synthetic reactions connecting easily available starting materials and products are found, and/or both biocatalytic and classical reactions of organic chemistry are utilized. Tools and ingredients for biocatalytic synthesis are of special interest for reactions difficult to achieve by classical organic synthesis. Densely and differentially functionalized small molecules do not allow much space for protecting or activating groups. Biocatalytic reactions have therefore performed well for a number of useful metabolites in enantiopure form to achieve full functionality. Although many well-known metabolites from classical biochemistry have only been prepared in racemic form, it is of fundamental interest to have these available in enantiomerically pure form. Biocatalytic reactions with nature's privileged chiral catalysts appear to be a promising synthetic strategy towards these metabolites, especially when sensitive or stable-isotope-labeled metabolites are to be prepared. The main applications for these metabolites are as references materials in metabolomics, as enzyme substrates for the characterization of metabolic enzyme activities and as potential pharmaceuticals in biomedical research. The use of stable-isotope-labeled metabolites can thereby simplify in vivo applications and metabolic flux analyses. 相似文献
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《FEBS letters》2014,588(8):1416-1422
Extracellular ATP is an important signaling molecule throughout the inflammatory cascade, serving as a danger signal that causes activation of the inflammasome, enhancement of immune cell infiltration, and fine-tuning of several signaling cascades including those important for the resolution of inflammation. Recent studies demonstrated that ATP can be released from cells in a controlled manner through pannexin (Panx) channels. Panx1-mediated ATP release is involved in inflammasome activation and neutrophil/macrophage chemotaxis, activation of T cells, and a role for Panx1 in inducing and propagating inflammation has been demonstrated in various organs, including lung and the central and peripheral nervous system. The recognition and clearance of dying cells and debris from focal points of inflammation is critical in the resolution of inflammation, and Panx1-mediated ATP release from dying cells has been shown to recruit phagocytes. Moreover, extracellular ATP can be broken down by ectonucleotidases into ADP, AMP, and adenosine, which is critical in the resolution of inflammation. Together, Panx1, ATP, purinergic receptors, and ectonucleotidases contribute to important feedback loops during the inflammatory response, and thus represent promising candidates for new therapies. 相似文献
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Amino Acids - Statins, including atorvastatin (Lipitor®), are the top-selling drugs in the world. The biocatalytic production of chiral side chains of statin drugs is of great interest to... 相似文献