An Intramolecular Anionic Migration of a Stannyl Group from the 6-Position of 1-(2-Deoxy- d - erythro -pent-1-enofuranosyl)uracil to the 2′-Position: Synthesis of 2′-Substituted 1′,2′-Unsaturated Uridines
作者:Hiroki Kumamoto、Satoru Shindoh、Hiromichi Tanaka、Yoshiharu Itoh、Kazuhiro Haraguchi、Eisen Gen、Atsushi Kittaka、Tadashi Miyasaka、Masato Kondo、Kazuo T Nakamura
DOI:10.1016/s0040-4020(00)00441-5
日期:2000.7
Lithiation of 1-[3,5-bis-O-(tert-butyldimethylsilyl)-2-deoxy-d-erythro-pent-1-enofuranosyl)uracil (1) takes place exclusively at the 6-position of the uracil base. The 6-tributylstannyl (or 6-trimethylsilyl) derivative prepared by quenching the C6-lithiated species with Bu3SnCl (or Me3SiCl) was found to undergo an intramolecular anionic migration to the 2′-positon of the furanoid glycal portion. By
1- [3,5-双-O-(叔丁基二甲基甲硅烷基)-2-脱氧-二赤-戊-1-烯呋喃糖基)尿嘧啶(1)的锂化仅在尿嘧啶碱基的6-位发生。发现通过用Bu 3 SnCl(或Me 3 SiCl)淬灭C6-锂化的物质而制备的6-三丁基锡烷基(或6-三甲基甲硅烷基)衍生物发生分子内阴离子迁移至呋喃糖基糖部分的2'-正电子。通过操纵2'-锡烷基,首次制备了2'-卤素和2'-碳取代的1',2'-不饱和尿苷。与报告的1的不稳定性相反在脱保护过程中,本研究中合成的2'-取代类似物经过NH 4 F的MeOH处理后,均一地以高收率均匀地提供了相应的游离核苷。