Sarkar A K, Jain R K, Matta K L
Department of Gynecologic Oncology, Roswell Park Memorial Institute, Buffalo, New York 14263.
Carbohydr Res. 1990 Aug 1;203(1):33-46. doi: 10.1016/0008-6215(90)80043-3.
Treatment of benzyl O-beta-D-galactopyranosyl-(1----3)-2-acetamido-2- deoxy-4,6-O-isopropylidene-beta-D-glucopyranoside with tert-butylchlorodiphenylsilane afforded the 6'-O-tert-butyldiphenylsilyl ether, which was converted into the 3',4'-O-isopropylidene derivative. Methylation and subsequent removal of protecting groups afforded benzyl O-(2-O-methyl-beta-D-galactopyranosyl)- (1----3)-2-acetamido-2-deoxy-beta-D-glucopyranoside (7). The trisaccharide methyl O-(2-O-methyl-beta-D-galactopyranosyl)-(1----3)-O-(2- acetamido-2-deoxy-beta-D-glucopyranosyl)-(1----3)-beta-D-galactopyranosi de (17) and the tetrasaccharide O-(2-O-methyl-beta-D-galactopyranosyl)-(1----3)-O-(2-acetamido-2-deoxy-b eta-D- glucopyranosyl)-(1----3)-O-beta-D-galactopyranosyl-(1----4)-D-glucopyran ose (32), both containing the 2'-O-methyllacto-N-biose I unit at the nonreducing end, were synthesized, and the structures of 7, 17, and 32 were confirmed by 13C-n.m.r. spectroscopy.
用叔丁基氯二苯基硅烷处理苄基O-β-D-吡喃半乳糖基-(1→3)-2-乙酰氨基-2-脱氧-4,6-O-异亚丙基-β-D-吡喃葡萄糖苷，得到6'-O-叔丁基二苯基硅烷基醚，其被转化为3',4'-O-异亚丙基衍生物。甲基化并随后除去保护基，得到苄基O-(2-O-甲基-β-D-吡喃半乳糖基)-(1→3)-2-乙酰氨基-2-脱氧-β-D-吡喃葡萄糖苷(7)。合成了三糖甲基O-(2-O-甲基-β-D-吡喃半乳糖基)-(1→3)-O-(2-乙酰氨基-2-脱氧-β-D-吡喃葡萄糖基)-(1→3)-β-D-吡喃半乳糖苷(17)和四糖O-(2-O-甲基-β-D-吡喃半乳糖基)-(1→3)-O-(2-乙酰氨基-2-脱氧-β-D-吡喃葡萄糖基)-(1→3)-O-β-D-吡喃半乳糖基-(1→4)-D-吡喃葡萄糖(32)，二者在非还原端均含有2'-O-甲基乳糖-N-二糖I单元，并且通过13C-核磁共振光谱确认了7、17和32的结构。
