A comparative study of different glycosylation methods for the synthesis of d-mannopyranosides of Nα-fluorenylmethoxycarbonyl- trans-4-hydroxy- l-proline allyl ester

Abstract

The synthesis of Nα-fluorenylmethoxycarbonyl- trans-4-hydroxy-4- O-[(2,3,4,6-tetra- O-acetyl)-α- d-mannopyranosyl]- l-proline allyl ester and Nα-fluorenylmethoxycarbonyl- trans-4-hydroxy-4- O-[(2,3,4,6-tetra- O-benzoyl)-α- d-mannopyranosyl]- l-proline allyl ester is described. Glycosylation using Königs–Knorr conditions with a benzoyl protected glycosyl donor provided the optimum method. Removal of the allyl ester gave two mannosylated building blocks suitable for solid phase glycopeptide synthesis.