909027-82-3Relevant academic research and scientific papers
Convenient synthesis of various substituted homotaurines from alk-2-enamides
Nai, Youfeng,Xu, Jiaxi
, p. 1355 - 1365 (2013/08/23)
Various substituted homotaurines (=3-aminopropane-1-sulfonic acids) 6 were readily synthesized in satisfactory to good yields via the Michael addition of thioacetic acid to alk-2-enamides 3 (→4), followed by LiAlH4 reduction (→5) and performic acid oxidation (Scheme 1). The configuration of 'anti'-disubstituted homotaurine 'anti'-6h was deduced from the 3-(acetylthio)alkanamide (=S-(3-amino-1,2-dimethyl-3-oxopropyl) ethanethioate)'anti'-4h formed in the Michael addition, which was identified via the Karplus equation analysis, and confirmed by X-ray diffraction analysis. The current route is an efficient method to synthesize diverse substituted homotaurines, including 1-, 2-, and N-monosubstituted, as well as 1,2-, 1,N-, 2,N-, and N,N-disubstituted homotaurines (Table). Copyright
Steroselective hydrolysis of DL-beta-acetylthioisobutyramide catalyzed by genetically engineered E. coli immobilized on Celite 580 in a packed bed bioreactor
Shaw, Shyh-Yu,Chen, Yu-Jen,Ou, Jung-Jung,Ho, Lewis
, p. 1607 - 1613 (2008/09/16)
Pseudomonas putida IFO12996 catalyzes the stereoselective hydrolysis of methyl DL-β-acetylthioisobutyramide (DL-ATIA) to form D-β- acetylthioisobutyric acid (DAT), a key intermediate for synthesis of a series of angiotensin converting enzyme inhibitors. The esterase gene of Pseudomonas putida IFO12996 was cloned and expressed in Escherichia coli which was further immobilized and retained on a packed bed bioreactor filled with Celite 580. The packed bed bioreactor was used to conduct the stereoselective hydrolysis of DL-ATIA and to give DAT with a yield of 34.5%, enantiometric excess value of 97% and enantioselectivity value > 150. The optimal pH and temperature for the reaction were 9.0 and 57 °C ～ 67 °C, respectively. The kinetic constants (Km and Vmax) of immobilized cells were found to be 372.5 mM and 285.7 μmol min-1 (g cell)-1, respectively. The immobilized cells retained over 60% of the initial catalytic activity after 5 batch cycles of production. This paper presents a simple, practical and economical process of immobilization of genetically engineered E. coli on a novel packed bed bioreactor for production of DAT.
