Total synthesis of an enantiomeric pair of FR900482. 2. Syntheses of the aromatic and the optically active aliphatic segments
作者:Toshiharu Yoshino、Yuriko Nagata、Etsuko Itoh、Masaru Hashimoto、Tadashi Katoh、Shiro Terashima
DOI:10.1016/s0040-4020(97)00651-0
日期:1997.7
The synthesis of the aromatic segment 4 was achieved starting from commercially available 5-hydroxyisophthalic acid (6) by utilizing Claisen rearrangement of 9, bromolactonization of 12, and modified Curtius rearrangement of 16 as the key steps. Furthermore, the optically active aliphatic segments 5 and ent-5 were synthesized in enantiomerically pure forms starting with natural (2R,3R)- and unnatural
芳香族链段4的合成是通过利用9的Claisen重排,12的溴内酯化和16的修饰的Curtius重排从商业上可获得的5-羟基间苯二甲酸(6)开始实现的。此外,旋光性脂肪族链段5和ent- 5以对映体纯净的形式分别从天然(2R,3R)-和非天然(2S,3S)-酒石酸二乙酯(7和ent- 7)合成:合成方案具有26个环氧化物的特征,27个亲环氧化物的特征与叠氮化物阴离子,在33的叠氮化物功能还原为胺,并形成N保护的1,3-恶唑烷35。