The new quinoline alkaloid folipidine, the structure of which was established by chemical transformations and spectral data (UV, IR, mass, NMR) using APT, 2D 1H-1H COSY, NOESY, and 1H- 13C HSQC, HMBC, was isolated from two plants of the Haplophyllum genus. Folipidine is the first representative of a new type of quinoline alkaloids that contain a heteroaromatic skeleton of [3,4-b] conjugated pyrrole and quinoline fragments. The total alkaloids of these plants exhibit antitumor activity. Folipidine does not possess such activity. ©2005 Springer Science+Business Media, Inc.