Synthesis of 6,3'-methanocytidine,6,3'-methanouridine, and their 2'-deoxyribonucleosides (nucleosides and nucleotides. LXXVII).
作者:YUICHI YOSHIMURA、TOMOHARU SANO、AKIRA MATSUDA、TOHRU UEDA
DOI:10.1248/cpb.36.162
日期:——
Condensation of 5-O-tert-butyldimethylsilyl-1, 2-O-isopropylidene-α-D-erythro-3-pentulo-furanose (4) with 2, 4-dimethoxypyrimidin-6-ylmethyllithium (5) afforded a 3-pyrimidinylmethyl-ribose derivative (6). The protecting groups of 6 were changed to give the 5-O-benzoyl-1, 2-di-O-acetyl derivative (8). The intramolecular glycosylation of 8 by treatment with stannic chloride furnished the 6, 3'-methanol-O4-methyluridine derivative (9), which was further converted to 6, 3'-methanouridine (10) and 6, 3'-methanocytidine (11). The 2'-deoxygenation of 9 by way of the 2'-imidazolylthiocarbonyl dericative gave, after appropriate derivatization, 2'-deoxy-6, 3'-methanocytidine (16) and -uridine (17).
5-O-叔丁基二甲基硅基-1,2-O-异亚丙基-α-D-赤式-3-戊基呋喃糖(4)与 2,4-二甲氧基嘧啶-6-基甲基锂(5)缩合,得到 3-嘧啶基甲基核糖衍生物(6)。改变 6 的保护基团,得到 5-O-苯甲酰基-1,2-二-O-乙酰基衍生物(8)。用氯化锡处理 8 分子内糖基化,得到 6,3'-甲醇-O4-甲基尿苷衍生物(9),进一步转化为 6,3'-甲尿苷(10)和 6,3'-甲胞苷(11)。通过 2'-咪唑基硫代羰基衍生物对 9 进行 2'-脱氧反应,经适当衍生化后,得到 2'-脱氧-6,3'-甲氰胞苷 (16) 和尿苷 (17)。