The crystal structure of 1,2,3,4,6-penta-O-benzoyl-α-D-mannopyranose:: observation of C-H•••π interaction as a surrogate to O-H•••O interaction of a free sugar

The crystal structure of the title compound was determined by X-ray crystallography. The compound crystallized in the orthorhombic space group P2(1)2(1)2(1) with four molecules in the unit cell with a = 9.170(2), b = 9.873 (2), c = 38.831(8) A. The structure was refined to a R index of 0.041 for 7907 independent reflections. The mannopyranose unit adopts a distorted C-4(1) conformation. The structure depicts unique network of C-H (...)pi interactions, very closely resembling the pattern of O-H O-... interactions in free sugars. This intriguing and rare observation points to a notion that the supramolecular organization pertaining to a sugar is in-built in the pyranose ring itself. (C) 2003 Elsevier Ltd. All rights reserved.