2,2',3,3'-Tetra-O-benzoyl-6,6'-dideoxy-4,4'-di-O-mesyl-6,6'- dithiocyanato-alpha,alpha-trehalose.

The low-temperature X-ray crystal structure of 2,3-di-O-benzoyl-6-deoxy-4-O-mesyl-6-thiocyanato-alpha-D-glu copyranosyl 2,3-di-O-benzoyl-6-deoxy-4-O-mesyl-6-thiocyanato-alpha-D-glu copyranoside (the title compound), C44H40N2O17S4, is reported. The absolute configuration has been determined. The molecule has only approximate C2 symmetry but the differences in the orientation of the C(5) substituents and the torsion angles about the glycosidic linkage are very much less than in alpha,alpha-trehalose and its derivatives. Each of the hexopyranosyl residues has a nearly perfect 4C1 conformation. The planes of the phenyl rings of the benzoyl groups are oriented such that they are approximately perpendicular to the plane of the parent pyranose ring.