Petroleum ether and CHC13 extracts of stem, root bark, and leaves of Galipea longiflora were found active in vitro against Leishmania sp. and Trypanosoma cruzi at 100 µg/ml. The activity-guided fractionation of the extracts by chromatography afforded thirteen active compounds identified as 2-substituted quinoline alkaloids. Four new 2-alkylquinoline alkaloids were isolated and identified from leaves or trunk bark of G. longiflora: 4-methoxy-2-n-propylquinoline [10] (chimanine A), 2-(E)-prop-1′-enylquinoline [11] (chimanine B), 4-methoxy-2-(E)-prop-1′-enylquinoline [12] (chimanine C), and 2-(1′, 2′-trans-epoxypropyl)-quinoline [13] (chimanine D). These alkaloids are accompanied by eight known 2-substiruted quinolines (2–9), and by one known furo-(2, 3b)-quinoline alkaloid, skimmianine [1]. © 1993, American Chemical Society. All rights reserved.