Evaluation of spasmolytic activity of clausmarin-A. a novel coumarin from Clausena pentaphylla (Roxb.) DC.

Crude ethanolic (50%) extracts of five species of Clausena exhibited varying degrees of spasmolytic activity on the isolated guinea-pig ileum preparation. The aerial parts of Clausena pentaphylla had maximum activity. Its active principle clausmarin-A, a novel coumarin terpenoid, was evaluated in detail for spasmolytic activity in various in vivo and in vitro test models. The activity of clausmarin A compared favourably with that of papaverine.