Highly stereoselective C-α-d-ribofuranosylation. Reactions of d-ribofuranosyl fluoride derivatives with enol trimethylsilyl ethers and with allyltrimethylsilane
作者:Younosuke Araki、Naoki Kobayashi、Yoshiharu Ishido、Jun'ichi Nagasawa
DOI:10.1016/s0008-6215(00)90883-8
日期:1987.12
anomer to give a mixture. The C-allylation reaction gave only the α- d anomer. C-Pentanonylation, however, gave a mixture of diastereoisomers that could not be isolated. All reactions afforded almost the same results starting with either α- or β- d -ribofuranosyl fluoride. No reaction of the β anomer of 5 with 1-isopropyl-2-methyl-1-propenyl trimethylsilyl ether took place.
摘要2,3,5-三-O-甲基-d-呋喃核糖基氟化物(6),2,3-二-O-苄基-5-O-甲基-d-核呋喃糖基氟化物(7)和5-O-在57(6α,15;和6β,42),87(7α,22;和7β,65)和85.5(8α)中获得了苄基-2,3-二-O-甲基-d-呋喃呋喃糖基氟(8)。通过与N,N-二乙基-1,1,2,3,3,3-六氟丙胺,六氟丙烯与二乙胺的加成物反应,分别从相应的OH-1衍生物中分别得到3,35.5;和8β,50%)。这些氟化物和2,3,5-三-O-苄基-d-呋喃呋喃糖基氟(5)在硼的存在下与异丙烯基三甲基甲硅烷基醚,(Z)-1-乙基-1-丙烯基三甲基甲硅烷基醚和烯丙基三甲基硅烷反应用三氟化物·二乙基醚化物以高收率得到相应的1-d-呋喃呋喃糖基-2-丙烷,2-d-呋喃呋喃糖基-3-戊烷和3-d-呋喃呋喃糖基-1-丙烯。确认C-乙酰基化得到作为初始产物的α-d异构体,并且将α-d异