IMPROVED PROCESSES FOR THE PREPARATION OF PROTECTED -(+)-CATECHIN AND (-)-EPICATECHIN MOMOMERS, FOR COUPLING THE PROTECTED MONOMERS WITHAN ACTIVATED, PROTECTED EPICATECHIN MONOMER, AND FOR THE PREPARATION OF EPICATECHIN-(4.BETA.,8)-EPICATECHIN OR -CATECHIN DIMERS AND THEIR DIGALLATES

摘要

Improved processes for the preparation of tetra-O-benzyl protected -(+)- catechin, for the coupling of the tetra-O-benzyl protected -(+)-catechin or -(- )-epicatechin with a C-4 activated, tetra-O-benzyl protected -(-)-epicatechi n, for the galloylation of the (-)-epicatechin-(4.beta.,8)-(+)-catechin or -(-) - epicatechin dimer to the dimer digallates, and for the deprotection (i.e., debenzylation) of the protected -(-)-epicatechin dimers and protected -(-)- epicatechin dimer digallates are disclosed.