F. Winnik, J. Brisson, J. Carver
May 1, 1982
Citations
0
Influential Citations
33
Citations
Journal
Carbohydrate Research
Abstract
Abstract Methyl 2- O -allyl-4,6- O -benzylidene-3- O -(2,3,4,6-tetra- O -acetyl- α - d -mannopyranosyl)- α - d -mannopyranoside( 12 ) was prepared in 90 % yield by Helferich glycosylation of methyl 2- O -allyl-4,6- O -benzylidene- α - d -mannopyranoside ( 9 ) with tetra- O -acetyl- α - d -mannopyranosyl bromide ( 11 ). Removal of the benzylidene group and second Helferich glycosylation with 11 led to methyl 2- O -allyl-3,6-di- O -(2,3,4,6-tetra- O -acetyl- α - d -mannopyranosyl)- α - d -mannopyranoside ( 14 ) which, after deallylation and Zemplen deacetylation, gave the title compound 5. The disaccharides methyl 3- O -( α - d -mannopyranosyl)- α - d -mannopyranoside ( 7 ) and methyl 6- O -( α - d -mannopyranosyl)- α - d -mannopyranoside ( 6 ) have also been synthesized. Complete assignments of the 1 H-n.m.r. spectra of the compounds 5, 6 , and 7 are given.