The effect of benzyl amine on the efficiency of the base-catalyzed transamination of α-keto esters
摘要:
This paper describes the effect of benzyl amine on the base-catalyzed transamination of alpha-keto esters. Among various benzyl amines examined, o-HOC6H4CH2NH2 was found to be highly effective for the reaction, affording a wide variety of alpha-amino esters in good yields. The o-OH group of the benzyl amine facilitates the transamination process likely via H-bond. Moderate enantiomeric excess was obtained for alpha-amino ester when a quinine derived catalyst was used. (C) 2012 Elsevier Ltd. All rights reserved.
Organocatalytic Asymmetric Biomimetic Transamination: From α-Keto Esters to Optically Active α-Amino Acid Derivatives
作者:Xiao Xiao、Ying Xie、Cunxiang Su、Mao Liu、Yian Shi
DOI:10.1021/ja203138q
日期:2011.8.24
This paper describes an effective chiral base-catalyzed biomimetic transamination of α-ketoesters using simple benzyl amines. A wide variety of α-amino esters containing various functional groups can be synthesized in high enantioselectivity and reasonable yield.
A biomimetic enantioselective transamination of α-keto ester derivatives can be realized under mild conditions by using chiral quaternary ammonium arenecarboxylates in the absence of base additives. The corresponding α-aminoacids can be used as versatile intermediates for further synthetic transformations that furnish chiral pyrrolidine and octahydroindolizine derivatives.
MACROCYCLIC COMPOUNDS FOR INHIBITION OF TUMOR NECROSIS FACTOR ALPHA
申请人:Lee Jinbo
公开号:US20100152099A1
公开(公告)日:2010-06-17
The invention provides macrocyclic compounds and methods for their synthesis and use. In particular, the invention provides macrocyclic compounds that modulate the activity of tumor necrosis factor alpha and/or are useful in the treatment of medical conditions, such as, rheumatoid arthritis, psoriasis, and asthma.
a simple chiral BINOL-aldehyde catalyst or combining catalysts of a chiral aldehyde and Lewis acid ZnCl2, the asymmetric α-arylation, α-allylation, and α-benzylation of amino acid esters with the corresponding halohydrocarbons proceed smoothly, producing α,α-disubstituted α-aminoacids in moderate-to-high yields and good-to-excellent enantioselectivities. The asymmetric α-arylation reaction can be applied
Chiral Aldehyde–Palladium Catalysis Enables Asymmetric Synthesis of α-Alkyl Tryptophans via Cascade Heck-Alkylation Reaction
作者:Qi-Wen Shen、Wei Wen、Qi-Xiang Guo
DOI:10.1021/acs.orglett.3c01119
日期:2023.5.5
The first catalytic asymmetriccascade Heck-alkylation reaction of NH2-unprotected amino acid esters with N-(2-iodophenyl)allenamides is reported in this work. Under the promotion of a combining catalytic system comprising a chiral aldehyde, a chiral palladium complex, and the Lewis acid ZnCl2, the title reaction takes place smoothly, giving optically active α-alkyl tryptophan derivatives in moderate