Synthesis of (−)-Deoxypukalide, the Enantiomer of a Degradation Product of the Furanocembranolide Pukalide
作者:James A. Marshall、Elva A. Van Devender
DOI:10.1021/jo016048s
日期:2001.11.1
A convergent stereoselective synthesis of (-)-deoxypukalide is described. This substance has not yet been found in Nature but is obtained through deoxygenation of pukalide, the first naturally occurring furanocembrane to be structurally elucidated. The route features a new intraannular furan synthesis that entails treatment of a 4-oxopropargylic beta-keto ester with silica gel. The product of this
描述了(-)-脱氧普卡利德的会聚立体选择性合成。该物质尚未在大自然中发现,但是通过对普卡利德进行脱氧而获得的,普卡利德是第一个在结构上被阐明的天然呋喃脑膜。该路线以新的环内呋喃合成为特色,该合成需要用硅胶处理4-氧代炔丙基β-酮酸酯。以96%的收率形成了这种新反应的产物3-羧基2,5-桥连呋喃。合成策略受到分子力学计算的强烈指导,这为立体定义步骤提供了宝贵的见解,包括双键立体化学和丁烯内酯构型。