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Methyl tetra-O-acetyl-β-D-glucopyranuronate (1) and methyl tetra-O-acetyl-α-D-glucopyranuronate (3) were isolated as crystalline solids and their crystal structures were obtained. That of the β anomer (1) was the same as that reported by Root et al., while anomer (3) was found to crystallise in the orthorhombic space group P212121 with two independent molecules in the asymmetric unit. No other crystal forms were found for either compound upon recrystallisation from a range of solvents. The α anomer (3) was found to be an impurity in initially precipitated batches of β-anomer (1) in quantities <3%; however, it was possible to remove the α impurity either by recrystallisation or by efficient washing, i.e. the α anomer is not incorporated inside the β anomer crystals. The β anomer (1) was found to grow as prisms or needles elongated in the a crystallographic direction in the absence of the α impurity, while the presence of the α anomer (3) enhanced this elongation., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

1-Acetamido-1-deoxy-(4-O-β-d-glucopyranosyl-β-d-glucopyranose) (5) and 1-deoxy-1-(4-phenyl-1,2,3-triazolyl)-(4-O-β-d-glucopyranosyl-β-d-glucopyranose) (7) were synthesised from 1-azido-1-deoxy-(4-O-β-d-glucopyranosyl-β-d-glucopyranose) (2) and crystallised as dihydrates. Crystal structural analysis of 5·2H2O displayed an acetamide C(4) chain and stacked cellobiose residues. The structure of 7·2H2O featured π-π stacking and stacking of the cellobiose residues., (Copyright © 2014 Elsevier Ltd. All rights reserved.)

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., (Copyright © 2013 Elsevier Ltd. All rights reserved.)

The synthesis and crystallisation of the pharmaceutically important metabolite, paracetamol-O-glucuronide, is described. Hydrated and anhydrous forms of the target molecule have been characterised by PXRD, DSC and TGA. In addition, a methanol solvate has been analysed, including single crystal analysis, which represents the first structure solution for this system., (Copyright © 2011 Elsevier Ltd. All rights reserved.)