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The nmr spectra of the two anomers of 1-O-acetyl-3,4-di-O-isopropylidene-2,5-anhydro-D,L-allose (2a, 2b) are discussed. The reactions of D,L-3,4-di-O-isopropylidene-2,5-anhydroallose (1) with carbethoxymethylenetriphenylphosphorane, bromocarbethoxymethylenetriphenylphosphorane and ethyl triphenylphosphoranylidene pyruvate to give respectively the olefin derivatives 7, 9, and 10 and an internal Michael addition product 11 are described. From 11, two bis-homo anhydro-C-nucleosides having 6-azauracil (15) and 4-hydroxy-5-carbox-amidopyrazole (19) bases were synthesized.

Methyl β-nitroacrylate (1) reacted with furan to give the corresponding Diels–Alder adduct, which was converted to D,L-3,4-di-O-isopropylidene-2,5-anhydroallose (9) in a five-step sequence in 14% yield, based on 1. The conversion of 9 to its oxime, semicarbazone, and thiosemi-carbazone is described, as well as the synthesis of the free aldehyde 15, and of the Wittig reaction product 14.

From 1,2-O-isopropylidene-α-D-glucofuranose 1, the 6-amino-6-deoxy-l,2:3,5-di-O-isopropylidene-α-D-glucofuranose 6 was prepared in a four-step sequence in an overall 50% yield. The conversion of 6 to the 6-bromoacetamido-6-deoxy 10, 6-deoxy-6-isothiocyanato 11, and 6-(p-azido-o-nitroanilino)-6-deoxy 12 derivatives of D-glucose is described.