Assessment of synthetic methods for the preparation of N-β-d-glucopyranosyl-N′-substituted ureas, -thioureas and related compounds
作者:László Somsák、Nóra Felföldi、Bálint Kónya、Csaba Hüse、Katalin Telepó、Éva Bokor、Katalin Czifrák
DOI:10.1016/j.carres.2008.01.045
日期:2008.8
beta-d-glucopyranosyl isocyanate in refluxing toluene. Deprotection of O-peracetylated N-beta-d-glucopyranosyl-N'-acyl ureas either under base (NaOMe in MeOH at or below rt) or under acid (KHSO(4) or AcCl in MeOH at rt) catalyzed transesterification conditions resulted in unavoidable partial cleavage of the N'-acyl moieties. Reaction of beta-d-glucopyranosylammonium carbamate with an isocyanate, isothiocyanate or isoselenocyanate
O-过乙酰化的N-β-d-吡喃葡萄糖基-N'-酰基脲衍生物的制备在以下条件下形成端基异构体混合物:在ZnCl存在下,酰氯将O-过乙酰化的β-d-吡喃葡萄糖基脲酰化(2)在回流的CHCl(3)中;在室温下,将O-过乙酰化的β-d-吡喃葡萄糖胺加到乙腈中的酰基异氰酸酯上;在回流甲苯中将羧酰胺添加到原位制备的O-过乙酰化的β-d-吡喃葡萄糖基异氰酸酯中。在碱下(NaOMe在rt或以下的MeOH中)或在酸(KHSO(4)或rt在MeOH中的accl)催化的酯交换条件导致O-全乙酰化N-β-d-吡喃葡萄糖基-N'-酰基脲的脱保护N'-酰基部分不可避免的部分裂解。β-d-吡喃葡萄糖基氨基甲酸铵与异氰酸酯的反应,