An n.m.r. and conformational analysis of the terminal trisaccharide from the serologically active glycolipid of Mycobacterium leprae in different solvents

Article abstract of DOI:10.1016/0008-6215(90)84180-3

The 1H- and 13C-n.m.r. spectra of allyl 2-O-<4-O-(3,6-di-O-methyl-β-D-glucopyranosyl)-2,3-di-O-methyl-α-L-rhamnopyranosyl>-3-O-methyl-α-L-rhamnopyranoside (3), a glycoside of the terminal trisaccharide found in the phenolic glycolipid I from Mycobacterium leprae, and those of the two component disaccharides, allyl 4-O-(3,6-di-O-methyl-β-D-glucopyranosyl)-2,3-di-O-methyl-α-L-rhamnopyranoside (1) and allyl 2-O-(2,3-di-O-methyl-α-L-rhamnopyranosyl)-3-O-methyl-α-L-rhamnopyranoside (2) have been assigned completely by 1D and 2D techniques.The preferred conformations, determined by chemical shift and n.O.e. studies, were different in D2O, CD3OD, and CDCl3.The preferred conformation of 3 accorded with the results of hard-sphere exo-anomeric (HSEA) calculations.