C. Nativi, J. Reymond, P. Vogel
Aug 9, 1989
Citations
0
Influential Citations
22
Citations
Journal
Helvetica Chimica Acta
Abstract
Ethyl and tert-butyl azidoformate added to 7-oxabicyclo[2.2.1]hept-5-en-2-one dimethyl (5) and dibenzyl (6) acetals to give mixtures of regioisomeric triazolines. The latter gave the corresponding aziridines (6,6-dialkoxy-3-aza-8-oxatricyclo[3.2.1.02,4]octane-3-carboxylates 15, 19, 23, and 27 and 31) on UV irradiation. In the presence of protic acids, the aziridines were rearranged into protected amines ([3-endo-alkoxy-5-oxo-7-oxabicyclo[2.2.1]hept-2-exo-yl]carbamates 16, 20, 24, and 28 and 33). Using (+)-(1R, 4R)-5,5-bis(benzyloxy)7-oxabicyclo[2.2.1]hept-2-ene((+)-6) derived from furan and l-cyanovinyl (1S)-camphanate, the method was applied to prepare 2-O-benzyl-3-[(tert-butoxy)carbonyiamino]-5-O-(3-chlorobenzoyl)-3-deoxy-β-D-altrofuranurono-6,1-lactone ((−)-37). This compound was converted to methyl 3-amino-3-deoxy-α-D-altropyranoside hydrochloride (44) and several derivatives.