New Compounds from Seaweeds and Higher Plants

In the course of our continuing phytochemical investigations on seaweeds and higher plants, a number of terrestrial plants and marine algae were examined. As a result of these studies, we were able to isolate several new secondary metabolites during the last two years. These metabolites belong to the classes sesquiterpenoids, acyclic diterpenoids, triterpenoids, triterpenoidal saponins, steroidal saponins, flavones, flavone glucosides and alkaloids. Among them the most interesting triterpenoid ( 6 ) named perovskone having a new carbon skeleton is particularly noteworthy, whose structure was elucidated by X-ray crystallography. The results of the studies on the isolation and spectroscopic characterization of some interesting chemical constituents are presented here.