Process for preparing kifunensine (cyclic oxamide derivative of 1-amino-mannojirimycin) intermediate and kifunensine therefrom

摘要

A process for the preparation of a compound of formula (I) or its salt is disclosed, wherein: R1 and R2 are each independently protecting groups which together with O to which they are attached, form 5-, 6-, 7- or 8-membered ring; and R3 is H or a protecting group; wherein the process includes the steps of: (a) protecting the hydroxyl group at the C-6 position of an N-protected-D-mannosamine, to give a 6-O-protected-N-protected-D-mannosamine; (b) reducing the C-1 anomeric carbon of the 6-O-protected-N-protected-D-mannosamine to give a 6-O-protected-N-protected-D-mannitol; (c) protecting the four hydroxyl groups of the 6-O-protected-N-protected-D-mannitol; and (d) removing the nitrogen atom protecting group and optionally removing the C-6 oxygen atom protecting group to give the compound of formula (I). The compound of formula (I) can be further used in the preparation of a cyclic oxamide derivative of 1-amino-mannojirimycin commonly known as kifunensine.