STEREOSELECTIVE CATALYTIC DOUBLE OSMYLATION OF 1,2-DIHYDROPYRIDINES LEADING TO AMINO-ARABINOSE AND TO AMINO-ALTROSE DERIVATIVES AND TO POTENTIAL GLYCOSIDASE INHIBITORS

Catalytic double osmylation of 1,2-dihydropyridines 1b and 1c proceeded stereospecifically and in good yields to the corresponding aminoarabinose 2b, and aminoaltrose 2c derivatives, respectively. In basic medium these piperidinoses equilibrated with their furanose isomers 6b and 6c (both alpha- and beta-anomers). Hydrogenolysis of their urethane moieties led to the corresponding piperidine triols 7a and 7b.