Nucleosides and nucleotides. LIX. Synthesis of 2'-deoxy-6,2'-methano-cyclouridine.
作者:TOMOHARU SANO、HIDEO INOUE、TOHRU UEDA
DOI:10.1248/cpb.33.3595
日期:——
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。