A NOVEL FURANOSIDE SYNTHESIS . CONVERSION OF METHYL 6-DEOXY-6-NITRO-ALPHA-D-GLUCOPYRANOSIDE INTO METHYL 3-DEOXY-3-NITRO-BETA-L-RIBO- AND -ARABINOFURANOSIDES AND CORRESPONDING AMINO SUGARS

A novel way of synthesizing methyl 3-amino-3-deoxypentofuranosides is described. Methyl 2,3,4-tri-O-acetyl- 6-deoxy-6-nitro-α-D-glucopyranoside (1) was prepared by an improved procedure and methanolized by catalysis with methyl p-toluenesulfonate to give crystalline methyl 6-deoxy-6-nitro-α-D-glucopyranoside (2). Periodic acid oxidation of 2 to dialdehyde 3 (not isolated), internal nitroalkane-aldehyde addition in the latter at pH 7.5 to a mixture of stereoisomeric methyl 5-aldo-3-deoxy-3-nitro-pentofuranosides (4, not isolated), and subsequent sodium borohydride reduction gave crystalline methyl 3-deoxy-3-nitro-β-L-ribofuranoside (5, major isomer) and methyl 3-deoxy-3-nitro-β-L-arabinofuranoside (6, minor isomer). The sequence constitutes a shortening of a sugar chain “from within,” without chemical involvement of the glycosidic center. Catalytic hydrogenation and derivatization by standard procedures led, from 5, to the corresponding amine hydrochloride (7), the amine 8,and the acetamido derivative 9. Acid hydrolysis of 7 gave known 3-amino-3-deoxy-L-ribose hydrochloride (10). A similar sequence performed with 6 gave the corresponding amino (11), isopropylidenamino(12), and acetamido (13) derivatives and finally, known 3-amino-3-deoxy-i^arabinose hydrochloride (14). © 1968, American Chemical Society. All rights reserved.