Synthesis of branched-chain, pyrrolidino-sugar derivatives related to apiose

• Published in: Carbohydrate research 1975-12, Vol.45 (1), p.91-103
• Main Authors: Ball, D.H., Bissett, F.H., Halford, M.H., Long, L.
• Format: Article
• Language: English
• ISSN: 0008-6215; 1873-426X
• DOI: 10.1016/S0008-6215(00)85869-3

3-C-(Acetamidomethyl)-1,2-O-isopropylidene-β-l-threofuranose (4) and the 3-acetate (5) have been prepared in high yields from mono-O-isopropylidene-d-apiose [3-C-(hydroxymethyl)-1,2-O-isopropylidene-β-l-threofuranose] (1). Acid-catalyzed methanolysis of 4 caused migration of the isopropylidene group and the formation of methyl 4-acetamido-4-deoxy-3-C-(hydroxymethyl)-2,3-O-isopropylidene-β-d-erythrofuranoside (8) in 25% yield. The major product (45%) from the acetolysis of 4 was also a pyrrolidine derivative, namely, 4-acetamido-3-C-(acetoxymethyl)-1-O-acetyl-4-deoxy-2,3-O-isopropylidene-β-d-erythrofuranose (10). Acetolysis of 5 removed the isopropylidene group and gave four acetylated pyrrolidines (isomeric at C-1 and C-2). Conditions which resulted in minimal epimerization at C-2 were established, and the major isomers 12 and 13 were isolated in reasonable yields. 1H- and 13C-n.m.r. data for equilibrium solutions of the pyrrolidines, and for intermediates 1-5, are given.