Act Cryst 2015 Gainsford Tyler Shwoerer Zubkova.pdf (943 kB)
Download fileCrystal packing in three related disaccharides: Precursors to heparan sulfate oligosaccharides
journal contribution
posted on 2021-11-18, 20:14 authored by GJ Gainsford, Ralf SchwoererRalf Schwoerer, Peter TylerPeter Tyler, Olga ZubkovaOlga ZubkovaThe 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.