Wotovic A, Jacquinet J C, Sinaÿ P
Laboratoire de Biochimie Structurale, U.R.A. 499, U.F.R.-Faculté des Sciences, Université d'Orléans, France.
Carbohydr Res. 1990 Sep 19;205:235-45. doi: 10.1016/0008-6215(90)80143-q.
Condensation of allyl 3,4-di-O-benzyl-beta-D-xylopyranoside with 2-O-acetyl-3,4,6-tri-O-benzyl-alpha-D-galactopyranosyl chloride in dichloromethane in the presence of silver triflate gave allyl 2-O-(2-O-acetyl-3,4-6-tri-O-benzyl-beta-D-galactopyranosyl)-3,4-di-O benzyl-beta-D-xylopyranoside (7, 83%). Compound 7 was converted in five steps into 2-O-(2-O-acetyl-3,4-6-tri-O-benzyl-beta-D-xylopyranosyl bromide (13), which was condensed immediately with allyl 2,3,6-tri-O-acetyl-4-O-(2,3,di-O-acetyl-beta-D-glucopyranosyl)-beta-D- glucopyranoside to give crystalline allyl O-(2-O-acetyl-3,4,6-tri-O-benzyl-beta-D-galactopyranosyl)- (1----2)-O-(3,4,-di-O-benzyl-alpha-D-xylopyranosyl)-(1----6)-O-(2,3,-di- O-acetyl-beta-D-glucopyranosyl)-(1----4)-2,3,6-tri-O-acetyl-beta-D-gluco pyranoside (23, 50%). O-Deacylation of 23 followed by catalytic hydrogenolysis gave the title glycoside.
在三氟甲磺酸银存在下,烯丙基3,4-二-O-苄基-β-D-吡喃木糖苷与2-O-乙酰基-3,4,6-三-O-苄基-α-D-吡喃半乳糖基氯在二氯甲烷中反应,得到烯丙基2-O-(2-O-乙酰基-3,4,6-三-O-苄基-β-D-吡喃半乳糖基)-3,4-二-O-苄基-β-D-吡喃木糖苷(7,产率83%)。化合物7经五步反应转化为2-O-(2-O-乙酰基-3,4,6-三-O-苄基-β-D-吡喃半乳糖基)溴化物(13),其立即与烯丙基2,3,6-三-O-乙酰基-4-O-(2,3-二-O-乙酰基-β-D-吡喃葡萄糖基)-β-D-吡喃葡萄糖苷缩合,得到结晶状的烯丙基O-(2-O-乙酰基-3,4,6-三-O-苄基-β-D-吡喃半乳糖基)-(1→2)-O-(3,4-二-O-苄基-α-D-吡喃木糖基)-(1→6)-O-(2,3-二-O-乙酰基-β-D-吡喃葡萄糖基)-(1→4)-2,3,6-三-O-乙酰基-β-D-吡喃葡萄糖苷(23,产率50%)。23进行O-脱酰基反应,随后进行催化氢解反应,得到标题糖苷。