First total synthesis of the natural product 1,3-di-O-galloyl-4,6-O-(S)-hexahydroxydiphenoyl-β-d-glucopyranoside

A straightforward synthesis of the natural product 1,3-di-O-galloyl-4,6-O-(S)-hexahydroxy-diphenoyl-β-d-glucopyranoside () was achieved based on a regio- and stereoselective galloylation of the 1,3-diol derivative of d-glucopyranose to the β-d-glucopyranoside . Subsequent acylation of monoester to the diester followed by the removal of the benzylidene protecting group led to the formation of the corresponding 4,6-diol derivative of d-glucopyranoside . A further double esterification of the (rac)-hexabenzyloxydiphenic acid with the appropriately substituted 4,6-diol derivative of d-glucopyranoside allowed us to assemble the carbon framework of the target . Hydrogenolysis of the tetraester as the precursor of the target compound over palladium on charcoal gave the natural product .