作者:Éva Bozó、Sándor Boros、János Kuszmann
DOI:10.1016/s0008-6215(97)00128-6
日期:1997.8
20% yield, respectively. The formation of these two derivatives is tentatively explained by involvement of a radical reaction mechanism. When O-(2,3- di -O- acetyl-4-azido-4-deoxy-5-thio -α- d - xylopyranosyl ) trichloroacetimidate was used as donor and boron trifluoride ethyl etherate as promoter, 31 and 33 were formed in excellent yield (96%) in a 2:1 ratio. The glycosides, obtained on deacetylation
摘要1-阿拉伯糖二乙基二硫缩醛通过其4-叠氮基-5-S-苯甲酰基-4-脱氧-2,3-O-异亚丙基-5-硫代-木糖二乙基二硫缩醛转化为4-叠氮基-4-脱氧5-硫代-α-d-木吡喃糖三乙酸盐29。在三氟甲磺酸三甲基甲硅烷基酯存在下,用4-氰基硫酚对29进行糖基化,得到了4-氰基苯基2,3-二-O-乙酰基-4-叠氮基-4-脱氧-1,2-二硫代-α-和-β-d-吡喃吡喃糖苷31和33以及3-O-乙酰基2,5-脱水4-叠氮基4-脱氧-5-硫代d-甘露糖双(4-氰基苯基)二硫缩醛34分别以8:2:1的比例存在比率。在乙酸中用溴化氢处理29得到2,3-二-O-乙酰基-4-叠氮基-4-脱氧-5-硫代-d-吡喃木糖基溴化物38和2,3-二- O-乙酰基5-溴5-脱氧4-硫基-1-阿拉伯呋喃糖基溴化物40。在碳酸钾存在下,溴化物38和40的混合物与4-氰基硫代苯酚的反应仅痕量提供了预期的31和33,而2-(1