BETA-ACARBOSE .4. MODEL STUDIES ON THE ALKYLATION OF CYCLOHEXYLAMINE WITH A CARBOHYDRATE EPOXIDE

1,6:3,4-Dianhydro-2-O-benzyl-beta-D-galactose has been treated with cy clohexylamine to give an amino alcohol, convertible into 6-anhydro-4-c yclohexylamino-4-deoxy-beta-D-glucose by reduction and acetylation. Th e anhydro bridge of this diacetate has been successfully opened under acetolysis conditions. The original amino alcohol has also been conver ted into a cyclic carbamate, a carbamate and an aziridine, by utilizin g a variety of reagents and conditions. The 1,6-anhydro bridge of the cyclic carbamate, also containing a 2-O-benzyl ether, could be opened under acetolysis conditions but a comparable reaction was best done on the derived 2-O-acetyl compound. The resulting mixture of D-glucosyl acetates, still containing a cyclic carbamate, was convered into a met hyl beta-D-glucoside. The cyclic carbamate could be removed by hydroly sis with aqueous base to give a model glycoside for a synthesis of bet a-acarbose. Single-crystal X-ray structure determinations are reported for lohexyl)amino]-1,6-anhydro-4-deoxy-beta-D-glucose, -[N-(cyclohexy l)epimino]-3,4-dideoxy-beta-D-allose and methyl rbonyl-4-cyclohexylami no-4-deoxy-beta-D-glucoside.