Stereoselective synthesis of naturally occurring unsaturated amide alkaloids by a modified RambergBäcklund reaction
作者:Yang Li、Yu Zhang、Zhi Huang、Xiaoping Cao、Kun Gao
DOI:10.1139/v04-028
日期:2004.5.1
A convenient and rapid approach for the synthesis of naturally occurring unsaturated amide alkaloids 1a1n by the recently developed one-flask RambergBacklund reaction is described. The starting material was alcohol 3, which was transformed into thiolacetate 4 using the Mitsunobu reaction. In situ cleavage of acetyl moiety of 4, followed by alkylation of the resulting thiol with appropriate chloroacetamide
描述了一种通过最近开发的单瓶 Ramberg??Backlund 反应合成天然存在的不饱和酰胺生物碱 1a??1n 的方便快捷的方法。起始原料是醇 3,使用 Mitsunobu 反应将其转化为硫代乙酸酯 4。4 的乙酰基部分的原位裂解,然后用合适的氯乙酰胺 5 将所得硫醇烷基化,提供硫化物 6。硫化物 6 氧化得到相应的砜 2。在氧化铝-存在下用二溴二氟甲烷处理砜 2二氯甲烷溶液中负载的氢氧化钾得到不饱和酰胺生物碱1a??1n。据我们所知,1e和1i的合成是首次报道。关键词:合成,不饱和酰胺生物碱,Ramberg??Backlund反应。