Efficient kinetic resolution of amino acids catalyzed by lipase AS ‘Amano’ via cleavage of an amide bond
摘要:
Herein the efficient kinetic resolution of non-natural alpha-amino acids catalyzed by lipase AS 'Amano' via cleaving the amide bond is reported. The starting materials were the corresponding amino acid amides and the amino acids were generated with ees of up to 99% with E values of > 600. These results indicated that the lipase AS 'Amano' could be a powerful amide hydrolase for the kinetic resolution of amino acid starting from the corresponding amino acid amides. (C) 2012 Elsevier Ltd. All rights reserved.
Asymmetric Synthesis of Unnatural Amino Acids and Tamsulosin Chiral Intermediate
作者:Veera Reddy Arava、Srinivasulu Reddy Amasa、Bharat Kumar Goud Bhatthula、Laxmi Srinivas Kompella、Venkata Prasad Matta、M. C. S. Subha
DOI:10.1080/00397911.2012.748075
日期:2013.11.2
An efficient and enantioselective hydrogenation of N-acetylamino phenyl acrylic acids was successfully developed by using ruthenium catalyst. This methodology is important in the field of pharmaceuticals and provides a new process for the preparation of unnatural amino acids and tamsulosin chiral intermediate. [Supplementary materials are available for this article. Go to the publisher's online edition of Synthetic Communications (R) for the following free supplemental resource: Full experimental and spectral details.]
Novel atropisomeric bisphosphine ligands with a bridge across the 5,5′-position of the biphenyl for asymmetric catalysis
A new type of atropisomeric bisphosphine ligand 2 with a bridge across the 5,5'-position of the biphenyl has been developed. The axial chirality of this type of ligands can be retained by macrocyclic ring strain produced from 5,5'-linkage of the biphenyl even without 6,6'-substituents on the biphenyls. Ligand (R)-2a showed good catalytic activity and enantioselectivity for Rh(I)-catalyzed asymmetric hydrogenation of (Z)-alpha-acetamidocinnamic acid 11. (C) 2008 Elsevier Ltd. All rights reserved.
Synthesis of a novel spiro bisphosphinite ligand and its application in Rh-catalyzed asymmetric hydrogenation
作者:Zhenqiu Guo、Xiaoyu Guan、Zhiyong Chen
DOI:10.1016/j.tetasy.2006.01.021
日期:2006.2
A novel, chiral bisphosphinite ligand (R)-SpiroBIP has been synthesized. The rhodium complex of the ligand was found to be highly enantioselective in the asymmetric hydrogenation of alpha-dehydroamino acid derivatives. (c) 2006 Published by Elsevier ltd.