[Studies on the alkaloids of Gynura segetum (Lour.) Merr].

Six alkaloids were isolated from Gynura segetum (Lour.) Merr. Four of them were identified. Alkaloids I and II were identified as known senecionine and seneciphylline, respectively. Alkaloids III and IV were found to be new compounds named seneciphyllinine and (E)-seneciphylline respectively. Their structures were confirmed on the basis of spectral data (UV, IR, MS, 1HNMR, 13CNMR, C-H COSY).