2'-Deoxy-6, 2'-methano-cyclouridine, a carbon-bridged cyclonucleoside fixed in a high-anti conformation, was synthesized. Treatment of a 3', 5'-O-protected 6-cyano-2'-O-imidazolythiocarbonyluridine with tri-n-butyltin hydride afforded a 6, 2'-oxomethano-cyclouridine derivative in low yield. Base treatment of 5-bromo-2'-deoxy-2' (S)-ethoxycarbonylmethyl-3', 5'-O-(tetraisopropyldisiloxane-1, 3-diyl) uridine resulted in an intramolecular Michael reaction followed by dehydrobromination to give the 6, 2'-cyclonucleoside. The latter was de-ethoxycarbonylated by treatment with sodium chloride and water in dimethylsulfoxide followed by desilylation to furnish the title compound.
2'-Deoxy-6, 2'-methano-cyclouridine 是一种以高反式构象固定的碳桥环核苷酸,其合成过程是这样的。用氢化三正
丁基锡处理 3',5'-O 保护的 6-
氰基-2'-O-
咪唑硫代羰基
尿苷,可以得到低产率的 6,2'-氧代甲氧基
环尿苷衍
生物。碱处理 5-
溴-2'-脱氧-2'(S)-乙氧羰基甲基-3', 5'-O-(tetraisopropyldisiloxane-1, 3-diyl)
尿苷导致分子内迈克尔反应,然后脱氢
溴化,得到 6, 2'- 环核苷。后者在
二甲基亚砜中用
氯化钠和
水进行脱乙氧基羰基化处理,然后脱
硅,得到标题化合物。