Syntheses of Metabolites ofS-Carboxymethyl-L-cysteine andS-Methyl-L-cysteine and of Some Isotopically Labelled (2H,13C) Analogues
作者:Claus O. Meese、Dagmar Specht、Ute Hofmann
DOI:10.1002/ardp.19903231205
日期:——
The chemical syntheses of human metabolites of S‐carboxymethyl‐L‐cysteine (3) and S‐methyl‐L‐cysteine (12) are described. The additional preparation of some 2H‐ and 13C‐labelled isotopomers enabled the direct evaluation of the stabilities of 3 and 12 under physiological conditions and also facilitated the unambiguous assignments of the signals in the 13C‐NMR spectra of all compounds mentioned.
Asymmetric synthesis of (<i>S,R</i>)- and (<i>R,R</i>)-methiin stereoisomers
作者:Anastasy О. Kolodiazhna、Аleksei I. Skliarov、Alena A. Slastennikova、Oleg I. Kolodiazhnyi
DOI:10.1080/10426507.2020.1755972
日期:2020.9.1
Abstract An asymmetric synthesis of (+)- and (–)-methiine (S-methyl-(R)-cysteine sulfoxide) diastereomers has been developed. These natural sulfur compounds were isolated from a variety of Brassica vegetables. As the starting compound, (R)-cysteine was used, which was methylated to form (R)-S-methylcysteine. Then the oxidation of S-methylcysteine with tert-butyl hydroperoxide catalyzed by the chiral
Asymmetric sulfoxidation of sulfur-containing L-amino acids was successfully achieved through bioconversion using IDO, which is an Fe(II)/alpha-ketoglutarate-dependent dioxygenase previously found in Bacillus thuringiensis strain 2e2. The IDO catalyzed sulfoxidation of L-methionine, L-ethionine, S-methyl-L-cysteine, S-ethyl-L-cysteine, and S-allyl-L-cysteine into the corresponding (S)-configured sulfoxides such as (+)-methiin and (+)-alliin, which are responsible for valuable physiological activities in mammals, and have high stereoselectivity. Herein we have established an effective preparative laboratory scale production method to obtain enantiomerically pure chiral sulfoxides using an IDO biocatalyst. (C) 2013 Elsevier Ltd. All rights reserved.