The metabolism of gallic acid and hexahydroxydiphenic acid in plants. Part 1. Introduction. Naturally occurring galloyl esters

Abstract
The present state of knowledge of the metabolism of gallic acid in higher plants is reviewed and its unique features are noted. Methods for the structure determination of natural galloyl-D-glucose esters are outlined and applied to the elucidation of the structure of several new galloyl-D-glucose derivatives isolated from the leaves of higher plants. Finally the structure of the ‘gallotannins’ based on β-penta-O-galloyl-D-glucose is reassessed on the basis of h.p.l.c. analysis and 13C n.m.r, spectroscopic measurements.