[EN] SYNTHESIS ROUTES TO 2(S),4(S),5(S),7(S)-2,7-DIALKYL-4-HYDROXY-5-AMINO-8-ARYL-OCTANOYL AMIDES [FR] VOIES DE SYNTHÈSE DES AMIDES 2(S),4(S),5(S),7(S)-2,7-DIALKYL-4-HYDROXY-5-AMINO-8- ARYL-OCTANOYLE
gem-Bromonitro compounds or gem-dinitro compounds couple with carbanions derived from α-cyano sulfones or α-carbonyl sulfones to give β-nitro sulfones. The nitro and sulfonyl groups are eliminated from the coupling products on treatment with reductive one electron transfer reagents to give α,β-unsaturated carbonyl compounds or nitriles.
FREE RADICAL CHAIN ELIMINATION REACTION (E<sub>RC</sub>1). CONVERSION OF VICINAL DINITRO COMPOUNDS OR β-NITRO SULFONES TO OLEFINS WITH TRIBUTYLTIN HYDRIDE
Vicinal dinitro compounds (1) or β-nitro sulfones (2) are converted to olefins in good yields on treatment with tributyltinhydride. This elimination proceeds by way of an electron transfer chain mechanism. The elimination from 1 is nonstereospecific and the elimination from 2 is stereospecific.
This Letter describes a versatile synthetic approach to prepare physovenine and physostigmine analogs. A series of analogs were synthesized and evaluated for cholinesterase inhibition activities, including human acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) from human serum.
An Enantioselective Total Synthesis and Stereochemical Revision of (+)-Citrinadin B
作者:Ke Kong、John A. Enquist、Monica E. McCallum、Genessa M. Smith、Takanori Matsumaru、Elnaz Menhaji-Klotz、John L. Wood
DOI:10.1021/ja405548b
日期:2013.7.31
This manuscript describes an enantioselectivesynthesis of the naturally occurring alkaloid citrinadin B. The synthetic effort revealed an anomaly in the original structural assignment that has led to the proposal of a stereochemicalrevision. This revision is consistent with the structures previously reported for a closely related family of alkaloids, PF1270A-C. The synthesis is convergent and employs
这份手稿描述了天然存在的生物碱 citrinadin B 的对映选择性合成。 合成工作揭示了原始结构分配中的异常,这导致了立体化学修订的提议。此修订版与先前报告的密切相关的生物碱家族 PF1270A-C 的结构一致。该合成是收敛的,并采用立体选择性分子间硝酮环化反应作为关键步骤。