Synthesis of 5-amino-5-deoxypentonolactams.

5-Azido-5-deoxy-1,2-O-isopropylidene-alpha-D-xylofuranose (4) and 5-azido-5-deoxy-1,2-O-isopropylidene-alpha-D-ribofuranose (10) were prepared starting from D-xylose and D-arabinose, respectively. Using the oxidation-reduction way for the C-3 epimerization, 5-azido-5-deoxy-1,2-O-isopropylidene-alpha-D-ribofuranose (15) and 5-azido-5-deoxy-1,2-O-isopropylidene-beta-D-lyxofuranose (17) were obtained from 4 and 10, respectively. The derivatives 4, 10, 15 and 17 afforded by acid hydrolysis, oxidation with bromine and catalytic hydrogenation successively the corresponding 5-azido-5-deoxyD-pentofuranoses 6, 11, 18, 19, 5-azido-5-deoxy-D-pentonolactones 7, 12, 20, 21 and 5-amino-5-deoxy-D-pentonolactams 8, 13, 22, 23.