Synthesis of lacto-N-neotetraose and lacto-N-tetraose using the dimethylmaleoyl group as amino protective group
作者:Mohamed R.E Aly、El-Sayed I Ibrahim、El-Sayed H El Ashry、Richard R Schmidt
DOI:10.1016/s0008-6215(99)00051-8
日期:1999.3
Similarly, reaction of O-[(2,3,4,6-tetra-O-acetyl-beta- D-galactopyranosyl)-(1-->3)-4,6-O-benzylidene-2-deoxy-2-dimethylmalei mido- alpha,beta-D-glycopyranosyl] trichloroacetimidate as donor with 8 as acceptor afforded the desired tetrasaccharide benzyl (2,3,4,6-tetra-O-acetyl-beta-D- galactopyranosyl)-(1-->3)-(4,6-benzylidene-2-deoxy-2-dimethylmaleimid o- beta-D-glucopyranosyl)-(1-->3)-(2,4,6-tri-O-benz
3)-(2,4,6-三-O-苄基-β-D-吡喃半乳糖基)-(1→4)-2,3,6-三-O-苄基-β-D-吡喃葡萄糖苷。用乙酰基取代N-二甲基马来酰基,进行O-去苄基化,最后进行O-去乙酰化,得到乳酸-N-新四糖。类似地,O-[(2,3,4,6-四-O-乙酰基-β-D-吡喃半乳糖基)-(1-> 3)-4,6-O-亚苄基-2-脱氧-2 -供体,以8为受体的-二甲基马来酸-mid,-α,β-D-甘露聚糖基]三氯乙酰亚胺酸酯,得到所需的四糖苄基(2,3,4,6-四-O-乙酰基-β-D-吡喃半乳糖基)-(1-- > 3)-(4,6-亚苄基-2-脱氧-2-二甲基马来酰亚胺邻-β-D-吡喃葡萄糖基)-(1-> 3)-(2,4,6-三-O-苄基-β- D-吡喃半乳糖基)-(1→4)-2,3,6-三-O-苄基-β-D-吡喃葡萄糖苷。除去亚苄基,用乙酰基取代N-二甲基马来酰基,然后进行O-乙酰化,得到四糖中间