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The synthesis of bivalent mannosides by the grafting of α-d-mannopyranoside onto monosaccharide acceptors and conjugation to terephthalic acid or phenylenediamine is described. Computational methods were used to predict accessible orientations and distances between the mannose units.

Participating acyl groups located at C-2 in glucosyl and related donors generally promote formation of 1,2-trans-glycosides. Reactions of some glucuronic acid donors with TMSN3/SnCl4 or ROH/SnCl4 gave only the 1,2-cis-glycoside. The stereoselectivity is consistent with participation of the C-6 group. The methodology was used for the synthesis of a Kdn2en mimetic with the α-configuration.

The synthesis of d-lyxo-hexos-5-ulose (5-ketomannose, 1,5-dicarbonyl sugar), a synthetic precursor to the glycoprocessing inhibitor deoxymannojirimycin, was carried out by an in situ epoxidation and hydrolysis of a trimethylsilyl-protected 6-deoxyhex-5-enopyranoside followed by facile removal of the protecting groups. A novel nine-step synthesis of deoxymannojirimycin has also been achieved from methyl α-d-mannopyranoside; this involved methanolysis of epoxides derived from an acetylated 1-azido-6-deoxyhex-5-enopyranoside followed by deprotection and catalytic hydrogenation.