Isolation of Cytotoxic Metabolites from Targeted Peruvian Amazonian Medicinal Plants

The antiproliferative bioassay-guided fractionation of five Peruvian plants, <i>Doliocarpus dentatus</i>, <i>Picramnia sellowii</i>, <i>Strychnos mitscherlichii, Iryanthera juruensis</i>, and <i>Croton alnifolius</i>, led to the isolation and identification of their different major cytotoxic constituents, betulinic acid (<b>1</b>), nataloe-emodin (<b>2</b>), bisnordihydrotoxyferine (<b>4</b>), 2′,4′-dihydroxy-6′-methoxy-3,4-methylenedioxydihydrochalcone (<b>5</b>), and 2′,4′-dihydroxy-4,6′-dimethoxydihydrochalcone (<b>6</b>) and 12-<i>O</i>-tetradecanoylphorbol-13-acetate (<b>7</b>), respectively. Eight human tumor cell lines and two nontumorigenic cell lines were used in this investigation. Their in vitro activity against <i>Mycobacterium tuberculosis</i> is also reported.