The synthesis of 1,2,3,4,6-penta-O-galloyl-[U-C-14]-D-glucopyranose is described. [U-C-14]glucopyranose was reacted with tri-O-benzylgallic acid forming 1;2,3,4,6-penta(tri-O-benzylgalloyl)-[U-C-14]-D-glucopyranose as chromatograpically separable anomers. Removal of the benzyl group by catalytic hydrogenation afforded 1,2,3,4,6-penta-O-galloyl-[U-C-14]-D-glucopyranose in 54% overall yield. GRAPHICS. Copyright (C) 2002 John Wiley Sons, Ltd.