Stereoselective Syntheses of the Octahydropyrano[2,3-b]pyridine DE Core of 'Upenamide via a Stannous Chloride-Induced Deacetalisation–Cyclisation Procedure
作者:Cécilia Ménard-Moyon、Richard J. K. Taylor
DOI:10.1002/ejoc.200700221
日期:2007.8
Two stereoselective syntheses of the octahydropyrano[2,3-b]pyridine DE hemiaminal core of the macrocyclic alkaloid 'upenamide are described. The syntheses proceeded through an efficient stannous chloride-induced deacetalisation–cyclisation procedure. The aza-annulation was stereoselective affording a single stereoisomer having the same relative configuration as in the natural product. The cis ring
描述了大环生物碱 'upenamide 的八氢吡喃并 [2,3-b] 吡啶 DE 半胺核的两种立体选择性合成。合成通过有效的氯化亚锡诱导的脱缩醛-环化过程进行。氮杂环化是立体选择性的,提供具有与天然产物相同的相对构型的单一立体异构体。顺式环结和 2-H 和 8a-H 之间的顺式关系通过核磁共振光谱建立并通过 X 射线晶体学证实。还公开了八氢吡喃并[2,3-b]吡啶环系统的不对称合成。(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)