Orthogonal cleavage of the 2-naphthylmethyl group in the presence of the p-methoxy phenyl-protected anomeric position and its use in carbohydrate synthesis

Abstract

Orthogonal removal of naphthylmethyl (NAP) and anomeric O-p-methoxyphenyl (PMP) ethers using 2,3-dichloro-5,6-dicyano-1,4-benzoquinone and cerium(IV) ammonium nitrate, respectively, is described. These reactions were tested in the oligosaccharide assembly of biologically relevant motifs, such as α-D-Man-(1,3)-[α-D-(1,6)-Man]-α-D-Man, α-D-Fuc-(1,2)-α-D-Fuc and α-D-NeuNAc-(2,3)-β-D-Gal. The usefulness of these chemoselective deprotections was proven in the synthesis of high mannoses.