Megastigmane glycosides from leaves of Eucommia ulmoidesOliver with ACE inhibitory activity
Jian-Kun Yan, Li-Qin Ding, Xu-Liu Shi, Paul Owusu Donkor, Li-Xia Chen, Feng Qiu
Four new megastigmane glycosides, eucomegastigsides A-D (2, 3, 5 and 7), together with three known megastigmane glycosides, (6R, 7E, 9R)-9-hydroxy-4, 7-megastigmadien-3-one-9-O-[α-l-arabinopyranosyl-(l → 6)-β-d-glucopyranoside (1), foliasalacioside B1 (4) and eleganoside A (6), were isolated from the leaves of Eucommia ulmoides Oliver. Their anti-hypertensive effect was investigated in vitro based on the inhibition of Angiotensin Converting Enzyme (ACE) using HPLC. The results showed that the isolates (2, 3, 4, 5, 7) had moderate inhibitory effects on ACE in vitro compared with captopril.
Circular dichroism, Absolute configuration, Natural products, Medicinal