Preparation of disaccharides having a β-d-mannopyranosyl group from N-phthaloyllactosamine derivatives by double or triple SN2 substitution
作者:Jocelyne Alais、Serge David
DOI:10.1016/0008-6215(90)84225-j
日期:1990.6
6'-O-anisylidene derivative, to give the 6'-O-(4-methoxybenzyl) ether 15. Conversion of 8 and 15 to their 2',4'-bis(trifluoromethanesulfonates), followed by SN2 reaction with benzoate, gave the corresponding beta-D-mannopyranosyl disaccharides. However, the model methyl 3-O-allyl-beta-D-galactopyranoside and 9 were converted into beta-D-mannopyranosyl derivatives in better yield (52-55%) by a one-pot, triple
1,2,3,4,6-戊基-O-乙酰基-β-D-吡喃半乳糖与3,6-二-O-苄基-2-脱氧-2-邻苯二甲酰亚胺基-β-D-吡喃葡萄糖苷甲基缩合通过碱性甲醇分解,得到具有未取代的β-D-吡喃半乳糖基的乳糖胺衍生物。三丁基氧化锡介导的烯丙基化产生的3'-O-烯丙基(9)收率高,3',6'-二-O-烯丙基醚(8)收率低。通过还原性地打开4',6'-O-苯二亚甲基衍生物,得到6'-O-(4-甲氧基苄基)醚15,可以在O-6'处保护9。将8和15转化为其2 ',4'-双(三氟甲磺酸酯),然后与苯甲酸酯进行SN2反应,得到相应的β-D-甘露吡喃糖基二糖。然而,