Fluorinated Analogues of Amicetose and Rhodinose - Novel Racemic and Asymmetric Routes
作者:Jonathan M. Percy、Ricard Roig、Kuldip Singh
DOI:10.1002/ejoc.200801130
日期:2009.3
ozonolysis in acidic methanol. A fortuitous separation of diastereoisomers allowed the diastereoisomeric pyranoses to be obtained cleanly. Though reductive defluorination allowed a facile entry to the route, the corresponding monofluoro sugar analogues could not be separated. Instead, Sharpless asymmetric epoxidation followed by epoxide ring-opening with an unusual nucleophilic fluoride source allowed
通过金属化二氟烯醇缩醛化学、保护、释放潜在的二氟甲基酮、立体选择性还原和酸性甲醇中的臭氧分解,三氟乙醇被转化为二氟(外消旋)类似物的乙酰氨基乙酸和红二糖。非对映异构体的偶然分离允许干净地获得非对映异构吡喃糖。尽管还原脱氟可以轻松进入该路线,但无法分离相应的单氟糖类似物。相反,Sharpless 不对称环氧化,然后用不寻常的亲核氟化物源进行环氧化物开环,可以获得对映异构高度富集和选择性保护的氟二醇。然后臭氧分解产生甲基吡喃糖苷,可以通过多种方式进行转化。