Synthesis of methyl 3-O- and 2-O-carbamoyl-α-D-mannopyranosides and carbamoyl-group migration between them

Abstract Methyl 3- O - and 2- O -carbamoyl-α- D -mannopyranosides, ( 2 and 3 ), were synthesized from methyl α- D -mannopyranoside via ammonolysis of a cyclic carbonate or a p -nitrophenoxycarbonate, as shown in Charts 1 and 2. Carbamoyl-group migration between the C-2 and C-3 hydroxyl groups, in methyl α- D -mannopyranoside under alkaline conditions, was also studied.