Hydrogen bonding in crystal forms of primary amide functionalised glucose and cellobiose

• Primary amide functionalised glucoses and cellobioses were synthesised and crystallised.
• Hydrogen bonding motifs involving both the glucopyranose and primary amide groups were observed.
• In an acetylated amido-sulfoxide, the amide groups formed a ladder-like hydrogen bonding motif.

A glucoside and cellobioside of glycolamide were synthesised and the crystal chemistry of these compounds investigated. The amidoglucoside crystallised in the P21 space group. The primary amide group participates in C(7) and C(17) chains also involving the pyranose oxygen and hydroxyl groups. The amidocellobioside crystallised as a methanol solvate in the P21 space group. The amide N–H groups donate hydrogen bonds to oxygen atoms on the cellobiose units, while intramolecular hydrogen bonds give rise to S(7) and S(9) motifs in addition to a R33 (9) motif. A tetra-O-acetylglucoside derivative of thioglycolamide and its sulfoxide derivative were synthesised to examine the effect of protecting the glucopyranose hydroxyl groups. The thioglycolamido derivative, which crystallised in the P212121 space group, featured amide N–H groups donating to the glucopyranose oxygen and an acetyloxy group. The sulfoxy derivative crystallised in the P21 space group and featured the primary amide groups forming R23(8) motifs generating a 21 ladder.

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