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Jiang C.,Zhejiang University of Science and Technology | Yan J.,Zhejiang Neo DanKong Pharmaceutical Co.
Letters in Organic Chemistry

The differences of (R)-glycidyl butyrate synthesis via hydrolytic kinetic resolution of glycidyl butyrate directly or regioselective opening epichlorohydrin as key steps by using Jacobsen's hydrotic kinetic resolution are compared. In the view of separation problem, it is hard to get the pure (R)-glycidyl butyrate by kinetic resolution of glycidyl butyrate directly. Via kinetic resolution of epichlorohydrin, treatment with butyric acid in the presence of CrCl 3 and then epoxidation with NaOH, the total yield of 38.5% and optical purity of 99% are obtained. © 2011 Bentham Science Publishers Ltd. Source

Jiang C.,Zhejiang University of Science and Technology | Hong H.,Zhejiang Neo DanKong Pharmaceutical Co.
Letters in Organic Chemistry

A practical chemical synthesis of ethyl (R)-(-)-4-Cyano-3- hydroxybutyrate((R)-CNHB) has been accomplished from (S)-3-chloro-1,2- propanediol, which is a main by-product originating from (S,S)-Salen Co(III) catalyzed by hydrolytic kinetic resolution (HKR) of epichlorohydrin. The new synthetic approach demonstrated an efficient utilization of organic by-product for the asymmetric synthesis of the intermediate of atorvastatin. © 2012 Bentham Science Publishers. Source


Crystalline sodium atorvastatin, compositions containing the same and methods for the production thereof.

Liu Z.-Q.,Zhejiang University of Technology | Ye J.-J.,Zhejiang University of Technology | Shen Z.-Y.,Zhejiang University of Technology | Hong H.-B.,Zhejiang Neo DanKong Pharmaceutical Co. | And 5 more authors.
Applied Microbiology and Biotechnology

(S)-4-chloro-3-hydroxybutanoate ((S)-CHBE) is an important chiral intermediate to synthesize the side chain of cholesterol-lowering drug atorvastatin. To biosynthesize the (S)-CHBE, a recombinant Escherichia coli harboring the carbonyl reductase and glucose dehydrogenase was successfully constructed. The recombinant E. coli was cultured in a 500-L fermentor; after induction and expression, the enzyme activity and cell biomass were increased to 23,661.65 U/L and 13.90 g DCW/L which was 3.24 and 2.60-folds compared with those in the 50 L fermentor. The biocatalytic process for the synthesis of (S)-CHBE in an aqueous-organic solvent system was constructed and optimized with a substrate fed-batch strategy. The ethyl 4-chloro-3-oxobutanoate concentration reached to 1.7 M, and the (S)-CHBE with yield of 97.2 % and enantiomeric excess (e.e.) of 99 % was obtained after 4-h reaction in a 50-L reactor. In this study, the space-time yield and space-time yield per gram of biomass (dry cell weight, DCW) were 413.17 mM/h and 27.55 mM/h/g DCW for (S)-CHBE production, respectively, which were the highest values as compared to previous reports. Finally, (S)-CHBE was extracted from the reaction mixture with 82 % of yield and 95 % of purity. This study paved the foundation for the upscale production of (S)-CHBE by biocatalysis method. © 2014, Springer-Verlag Berlin Heidelberg. Source

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