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Updated: Aug 19, 2026

Synthesis and Structure Determination of µ-Conotoxin PIIIA Isomers with Different Disulfide Connectivities
Published on: October 2, 2018
Enantioselective total synthesis of colomitides and their absolute configuration determination and structural
Hongguang Yang1, Xiaoyu Liu, Xiaoyu Li
1State Key Laboratory of Bioactive Substances and Functions of Natural Medicines, Institute of Materia Medica, Beijing Key Laboratory of Active Substances Discovery and Druggability Evaluation, Peking Union Medical College and Chinese Academy of Medical Sciences, Beijing 100050, PR China. jiaoxz@imm.ac.cn xp@imm.ac.cn.
Abstract:
An efficient stereoselective synthetic approach to colomitides, 2,7-dioxabicyclo[3.2.1]octane-type natural products, is reported. Key steps are a stereocontrolled aldol reaction and a gold-catalyzed cycloisomerization. This synthetic strategy has been applied for the first asymmetric total synthesis of the proposed colomitides and their possible diastereomers. Comparison of their 1H and 13C NMR spectra and specific rotations with those of the natural product revealed that the structure of colomitide A should be revised to 1c, and that the absolute stereochemistries of colomitides A and B are 2'R,4R,5R,8S,1R and 2'R,4S,5R,8S,1R.
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