Silver Zeolite as Promoter in Glycoside Synthesis. The Synthesis of beta-D-Mannopyranosides.

Abstract

Glycosylation of 4 protected monosaccharides each with 1 free OH group with 6-O-acetyl-2,3,4-tri-O-benzyl-α-D-mannopyranosyl bromide in PhMe or CH2Cl2 at room temp. in the presence of Ag zeolite gave 33-83% of the corresponding β-D-mannopyranosyl disaccharides, e.g., I (R = H) gave 83% I (R = β-Q) and 15% I (R = α-Q). [on SciFinder(R)]