Iridoid Glycosides from Vietnamese Ethno-Medicinal Plant Premna integrifolia

Iridoid glycosides are known as the main components of Vietnam medicinal plant, Premna integrifolia with broad biological activities. Using combination of various chromatographic methods, three iridoid glycosides were isolated including 10- O-trans - p -methoxycinamoylcatalpol (1), 10- O-cis - p -methoxycinamoylcatalpol (2), and 10- O-trans - p -coumaroylcatalpol (3). Their chemical structures were determined by analysis of NMR spectra, and as well as comparison with reported literature.