A concise synthesis of 7-desmethylasteriscanolide and the discovery of an unusual fragmentation reaction to the related asteriscunolide skeleton
作者:Kevin I. Booker-Milburn、Justin K. Cowell、Laurence J. Harris
DOI:10.1016/s0040-4020(97)00769-2
日期:1997.9
intramolecular [2+2] photocycloaddition of the α,β-unsaturated acid-ether 29 followed by a Curtius rearrangement/ruthenium tetroxide/fragmentation sequence to yield the cyclooctane lactones 32 and 33. Attempted methylation of 32 uncovered an interesting retro-Michael type fragmentation to the related naturally occuring asteriscunolide skeleton.
描述了7-去甲基紫杉醇内酯的简明合成。关键特征包括有效的α,β-不饱和酸醚29的分子内[2 + 2]光环加成反应,然后进行Curtius重排/四氧化钌/裂解序列,得到环辛烷内酯32和33。尝试对32位进行甲基化,发现了与相关的自然存在的阿斯古松内酯骨架有关的有趣的麦克尔逆转录片段。