[Studies on the chemical constituents of the root of Cocculus Trilobus DC].

Four bisbenzylisoquinoline alkaloids (I-IV) have been isolated from the roots of Cocculus trilobus DC. (Menispermaceae) growing wild in the mountainous areas of Zhejiang province. Their structures were established as isotrilobine (I), trilobine (II), isotrilobine-N-2-oxide (III) and nortrilobine (IV) on the basis of spectral analysis (UV, IR, HNMR,MS), physico-chemical constants and properties of the derivatives. III is a new alkaloid and IV was found from this plant for the first time.