32224-01-4Relevant articles and documents
Synthesis method of quaternary amine inner salt
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Paragraph 0078; 0079, (2019/01/14)
The invention discloses a synthesis method of quaternary amine inner salt. The synthesis method comprises the following steps: (a) reduction reaction: taking a compound having a structure shown as theformula I as a raw material, carrying out a reduction reaction among the compound, an apoenzyme, a dehydrogenase and a coenzyme in monosaccharide within a certain pH range, removing enzymes with active carbon and performing rectification, so as to obtain a reduced product shown in the original specification, wherein X represents one of chlorine, bromine and iodine in halogens, and R represents one of a saturated alkyl or an unsaturated alkyl; (b) synthesis of the quaternary amine inner salt: carrying out a reaction between an obtained product and trimethylamine under a strong base condition to obtain quaternary amine hydrochloride, exchanging the quaternary amine hydrochloride in ion exchange resin to remove halide ions, performing concentration and refining a concentrated product with alcohol and acetone, so as to obtain the quaternary amine inner salt. The synthesis method has the advantages of being high in yield in each step, simple to operate and mild in reaction conditions, effectively removing enzyme residues by introducing a chiral structure with a high-selectivity enzymatic method, avoiding a reagent with high toxicity and high pollution by utilizing renewable resin for desalting, obtaining the high-purity product, being suitable for industrial production and the like.
Asymmetric synthesis of optically active methyl-2-benzamido-methyl-3-hydroxy-butyrate by robust short-chain alcohol dehydrogenases from Burkholderia gladioli
Chen, Xiang,Liu, Zhi-Qiang,Huang, Jian-Feng,Lin, Chao-Ping,Zheng, Yu-Guo
, p. 12328 - 12331 (2015/07/27)
Three short-chain alcohol dehydrogenases from Burkholderia gladioli were discovered for their great potential in the dynamic kinetic asymmetric transformation of methyl 2-benzamido-methyl-3-oxobutanoate, and their screening against varied organic solvents and substrates. This is the first report of recombinant enzymes capable of achieving this reaction with the highest enantio- and diastereo-selectivity.
Facile access to chiral alcohols with pharmaceutical relevance using a ketoreductase newly mined from Pichia guilliermondii
Xu, Guochao,Yu, Huilei,Xu, Jianhe
, p. 349 - 354 (2013/08/22)
Chiral secondary alcohols with additional functional groups are frequently required as important and valuable synthons for pharmaceuticals, agricultural and other fine chemicals. With the advantages of environmentally benign reaction conditions, broad reaction scope, and high stereoselectivity, biocatalytic reduction of prochiral ketones offers significant potential in the synthesis of optically active alcohols. A CmCR homologous carbonyl reductase from Pichia guilliermondii NRRL Y-324 was successfully overexpressed. Substrate profile characterization revealed its broad substrate specificity, covering aryl ketones, aliphatic ketones and ketoesters. Furthermore, a variety of ketone substrates were asymmetrically reduced by the purified enzyme with an additionally NADPH regeneration system. The reduction system exhibited excellent enantioselectivity (>99% ee) in the reduction of all the aromatic ketones and ketoesters, except for 2-bromoacetophenone (93.5% ee). Semi-preparative reduction of six ketones was achieved with high enantioselectivity (>99% ee) and isolation yields (>80%) within 12 h. This study provides a useful guidance for further application of this enzyme in the asymmetric synthesis of chiral alcohol enantiomers. Copyright
