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Abstract:

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    The reaction of the dioxepane 2, obtained by periodate oxidation of methyl 4,6-O-benzylidene- -a-D-glucopyranoside, with nitromethane, using potassium fluoride as catalyst, g ave methyl 5,7-O- -benzylidene-3-deoxy-3-nitro-D-glycero-a-D-ido-heptoseptanoside (2) as the major product. The reaction of 4 with methyl nitriacetate followed by acetylation gave methyl 2,4-di-O-acetyl-5,7-O-benzylidene-3-deoxy-3-C- -methoxycarbonyl-3-nitro-D-glycero-a-D-talo (6) and -D-glycero-a-D-ido-heptoseptanoside (7).

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