Tannins and related compounds from Terminalia arborea

A chemical examination of the fruits of Terminalia arborea Koord. et Val. has led to the characterization of twenty four hydrolyzable tannins and related compounds. These compouuds included three phenolcarboxylic acids: decarboxyellagic acid (1), gallic acid (3) and chebulic acid (4); eight galloyl glucosides: 1-O-galloyl-β-D-glucose (7), 3-O-galloyl-D-glucose (8), 6-O-galloyl-D-glucose (9), 1,6-di-O-galloyl-β-D-glucose (10), 3,4-di-O-galloyl-D-glucose (11), 3,6-di-O-galloyl-D-glucose (12), 1,3,6-tri-O-galloyl-β-D-glucose (13), 2,3,4,6-tetra-O-galloyl-D-glucose (14); two galloyl shikimic acids: 5-O-galloyl-(-)-shikimic acid (5) and 3,5-di-O-galloyl-(-)-shikimic acid (6); six ellagitannins; 2.3-(S)-HHDP-D-glucose (15), 2,3-(S)-HHDP-6-O-galloyl-D-glucose (16), punicalagin (17), terchebulin (18), corilagin (20) and chebulagic acid (21); and five other hydrolyzable tannins: punicalin (19), chebulinic acid (24), neochebulinic acid (22), punicacortein C (23) and 1,3-di-O-galloyl-2,4-chebuloyl-β-D-glucose (2). Their structures were identified on the basis of spectroscopic and chemical evidence. Decarboxyellagic acid (1) and 1,3-di-O-galloyl-2,4-chebuloyl-β-D-glucose (2) were isolated for the first time from natural products.