Crystal and molecular structure of methyl α-d-galactopyranoside 3-(sodium sulfate) monohydrate

✍ Scribed by Angel J. Polvorinos; Rafael R. Contreras; Daniel Martin-Ramos; Jose Romero; Miguel A. Hidalgo

• Publisher: Elsevier Science
• Year: 1994
• Tongue: English
• Weight: 551 KB
• Volume: 257
• Category: Article
• ISSN: 0008-6215
• DOI: 10.1016/0008-6215(94)84103-9

✦ Synopsis

The crystal and molecular structure of methyl cY-D-galactopyranoside 3-(sodium sulfate) monohydrate has been determined by X-ray diffraction. The molecular structure has a distorted chair conformation 4C,. The conformation of the hydroxymethyl group is guuchecis and the methyl group is gauche-truns with respect to the pyranoid ring. The distorted sodium ion environment has seven closest oxygens of two different molecules. Coordination with (O-5, O-4, O-6) and (O-1, O-21, related by translational symmetry along the a axis, together with water oxygen 0-1W and O-9 of the sulfate group, completes the first coordination sphere of sodium. A complex hydrogen-bond pattern involves all oxygens of the sulfate group as acceptors, linking molecules in [loo] through O-7. The hydroxyl groups on C-2 and C-4 also participate in the bonding pattern. The complex packing by hydrogen bonds and ion coordination results in relevant differences with respect to the structure of other sulfate pyranosides.