Studies on the Constituents of Catalpa Species. VI. Monoterpene Glycosides from the Fallen Leaves of Catalpa ovata G. DON

Five new monoterpene glycosides, ovatolactone 7-O-(6′-O-p-hydroxybenzoyl)-β-D-glucopyranoside, ovatic acid methyl ester 7-O-(6′-O-p-hydroxybenzoyl)-β-D-glucopyranoside, 7-O-p-hydroxybenzoylovatol 1-O-(6′-O-p-hydroxybenzoyl)-β-D-glucopyranoside, 6′-O-p-hydroxybenzoylcatalposide and (2E, 6R)-2, 6-dimethyl-8-hydroxy-2-octenoic acid 8-O-[6′-O-(E)-p-coumaroyl]-β-D-glucopyranoside were isolated from the fallen leaves of Catalpa ovata G. DON. Their structures were determined by extensive spectroscopic studies and syntheses.