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

Abstract

A glucoside and cellobioside of glycolamide were synthesised and the crystal chemistry of these compounds investigated. The amidoglucoside crystallised in the P2(1) 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 P2(1) 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 R3(3) (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 P2(1)2(1)2(1) space group, featured amide N-H groups donating to the glucopyranose oxygen and an acetyloxy group. The sulfoxy derivative crystallised in the P2(1) space group and featured the primary amide groups forming R2(3)(8) motifs generating a 2(1) ladder.