Crystal packing in three related disaccharides: precursors to heparan sulfate oligosaccharides

Autor: Graeme J. Gainsford, Ralf Schwörer, Peter C. Tyler, Olga V. Zubkova
Jazyk: angličtina
Rok vydání: 2015
Předmět:
Zdroj: Acta Crystallographica Section E: Crystallographic Communications, Vol 71, Iss 6, Pp 582-587 (2015)
Druh dokumentu: article
ISSN: 2056-9890
20569890
DOI: 10.1107/S2056989015008518
Popis: The three title compounds form part of a set of important precursor dissacharides which lead to novel therapeutics, in particular for Alzheimer's disease. All three crystallize as poorly diffracting crystals with one independent molecule in the asymmetric unit. Two of them are isostructural: 4-methoxyphenyl 4-O-[6-O-acetyl-2-azido-3-O-benzyl-2-deoxy-4-O-(9-fluorenylmethyloxycarbonyl)-α-d-glucopyranosyl]-2-O-benzoyl-3-O-benzyl-6-O-chloroacetyl-α-l-idopyranoside, C59H56ClN3O16, (I), the ido-relative of a reported gluco-disaccharide [Gainsford et al., 2013). Acta Cryst. C69, 679–682] and 4-methoxyphenyl 4-O-[6-O-acetyl-2-azido-3-O-benzyl-2-deoxy-4-O-(9-fluorenylmethyloxycarbonyl)-α-d-glucopyranosyl]-2-O-benzoyl-3-O-benzyl-6-O-methoxyacetyl-α-l-idopyranoside, C60H59N3O17, (II). Both exhibit similar conformational disorder of pendant groups. The third compound 4-methoxyphenyl 4-O-[6-O-acetyl-2-azido-3,4-di-O-benzyl-2-deoxy-α-d-glucopyranosyl]-2-O-benzoyl-3-O-benzyl-6-O-methoxyoacetyl-β-d-glucopyranoside, C52H55N3O15, (III), illustrates that a slightly larger set of weak intermolecular interactions can result in a less disordered molecular arrangement. The molecules are bound by weak C—H...O(ether) hydrogen bonds in (I) and (II), augmented by C—H...π interactions in (III). The absolute configurations were determined, although at varying levels of significance from the limited observed data.
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