Stereoselectivity in the electrophile-mediated cyclization of 2,3,5-tri-O-benzyl-1,2-dideoxy-d-arabino-hex-1-enitol. A stereocontrolled synthesis of 1-amino-2,5-anhydro-3,4,6-tri-O-benzyl-1-deoxy-d-glucitol
作者:Fillmore Freeman、Kirk D. Robarge
DOI:10.1016/s0008-6215(00)90874-7
日期:1987.12
Abstract Cyclization of 2,3,5-tri-O-benzyl-1,2-dideoxy- d -arabino-hex-1-enitol (2) with mercuric acetate, mercuric trifluoroacetate, iodine, and N-bromosuccinimide gave preponderantly the allo isomer of the C-arabinofuranosyl structure. 1-Amino-2,5-anhydro-3,4,6-tri-O-benzyl-1-deoxy- d -glucitol, which is a key intermediate in the synthesis of 3-(β- d -arabinofuranosyl)pyrazole[4,3-d]pyrimidine-5
摘要用乙酸汞,三氟乙酸汞,碘和N-溴代琥珀酰亚胺对2,3,5-三-O-苄基-1,2-二脱氧-d-阿拉伯糖醇-己-1-烯醇(2)的环化作用主要产生同素异形体C-阿拉伯呋喃糖基结构的异构体。1-氨基-2,5-脱水-3,4,6-三-O-苄基-1-脱氧-d-葡萄糖醇,是合成3-(β-d-阿拉伯呋喃糖基)吡唑的关键中间体[立体选择性地以3个步骤从2的立体收率制备了4,3-d]嘧啶-5,7-二酮(氧代甲醛B的β-d-阿拉伯糖基差向异构体)。还讨论了环化的立体化学结果。