β-tert-Butyl aspartate as an organocatalyst for the asymmetric α-amination of α,α-disubstituted aldehydes
摘要:
The enantioselective alpha-amination reaction of alpha,alpha-disubstituted aldehydes can lead to a variety of enantioenriched amino aldehydes, amino alcohols, and amino acids. After screening a variety of amino acids and their derivatives, we identified a cheap, simple, commercially available aspartic acid derivative that can catalyze efficiently the reaction between alpha,alpha-disubstituted aldehydes and dialkyl azodicarboxylates. The reaction proceeds smoothly leading to the corresponding alpha-aminated adducts in moderate to quantitative yields and moderate to high enantioselectivities (up to 96% ee). Finally, the conversion of these adducts to alpha,alpha-disubstituted quaternary amino acids is also described. 2013 Elsevier Ltd. All rights reserved.
[EN] PYRAZOLOTRIAZOLOPYRIMIDINE DERIVATIVES AS A2A RECEPTOR ANTAGONIST<br/>[FR] DÉRIVÉS DE PYRAZOLOTRIAZOLOPYRIMIDINE EN TANT QU'ANTAGONISTE DU RÉCEPTEUR A2A
申请人:BEIGENE LTD
公开号:WO2020020097A1
公开(公告)日:2020-01-30
Disclosed herein is a pyrazolotriazolopyrimidine derivative or a stereoisomer thereof, or a pharmaceutically acceptable salt thereof useful as A2A receptor antagonist, and a pharmaceutical composition comprising the same. Also disclosed herein is a method of treating cancer using the pyrazolotriazolopyrimidine derivative or a stereoisomer thereof, or a pharmaceutically acceptable salt thereof as A2A receptor antagonist.
Primary Amine/CSA Ion Pair: A Powerful Catalytic System for the Asymmetric Enamine Catalysis
作者:Chen Liu、Qiang Zhu、Kuo-Wei Huang、Yixin Lu
DOI:10.1021/ol200747x
日期:2011.5.20
A novel ion pair catalyst containing a chiral counteranion can be readily derived by simply mixing cinchona alkaloid-derived diamine with chiral camphorsulfonic acid (CSA). A mixture of 9-amino(9-deoxy)epi-quinine 8 and (−)-CSA was found to be the best catalyst with matching chirality, enabling the direct amination of α-branched aldehydes to proceed in quantitative yields and with nearly perfect enantioselectivities
Enantioselective Synthesis of Planar‐Chiral Macrocycles through Asymmetric Electrophilic Aromatic Amination
作者:Donglei Wang、Ying‐Bo Shao、Yunrong Chen、Xiao‐Song Xue、Xiaoyu Yang
DOI:10.1002/anie.202201064
日期:2022.5.23
An efficient method for asymmetric synthesis of planar-chiral macrocycles has been developed through enantioselective electrophilic aromatic aminations with azodicarboxylates enabled by chiral phosphoric acid catalysis. A wide array of planar-chiral macrocycles bearing ansa chains with varied length (12-member to 19-member) and various functional groups were generated using this method with high to
of α,α-disubstituted aldehydes with azodicarboxylates promoted by a chiral carbamate-monoprotected cyclohexa-1,2-diamine as organocatalyst has been developed. The process was carried out without any solvent, and the corresponding α,α-disubstituted α-nitrogenated aldehydes were obtained with excellent yields and enantioselectivities up to 99% ee. The sustainability of the procedure was established through