Formation of septanoses from hexopyranosides via 5,6-exo-glycals Original Research Article

Methyl d-hexo-5-ulosides are obtained in high yield by dihydroxylation of 5,6-exo-glucal compounds. The bicyclic structure (1,6-anhydropyrano-5-ulose) of the products is adopted in solution and in solid state in a 4C1 conformation. This methodology has been used to prepare 1,6-anhydro-l-idopyrano-5-uloses. Further manipulation of the 1,6-anhydro bridge allowed the preparation of the yet unknown septano-5-uloses in moderate to high yields.