title: Cytotoxic beta-carbolines and cyclic peroxides from the Palauan sponge Plakortis nigra.
abstract: Four beta-carbolines, plakortamines A-D, two cyclic peroxides, epiplakinic acids G and H, and two related gamma-lactones, (2S,4R)- and (2R,4R)-2,4-dimethyl-4-hydroxy-16-phenylhexadecanoic acid 1,4-lactones, were isolated from the deep-water sponge Plakortis nigra from Palau. The structures of the eight new metabolites were elucidated by interpretation of spectroscopic data. Most of the metabolites inhibited the HCT-116 human colon tumor cell line.
mesh_terms: D000818:Animals; D000970:Antineoplastic Agents / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology; D002243:Carbolines / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology; D003110:Colonic Neoplasms; D006801:Humans; D020128:Inhibitory Concentration 50; D015394:Molecular Structure; D019906:Nuclear Magnetic Resonance, Biomolecular; D019029:Palau; D010545:Peroxides / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology; D011161:Porifera / Q000737:chemistry*; D013055:Spectrophotometry, Infrared; D013056:Spectrophotometry, Ultraviolet; D017550:Spectroscopy, Fourier Transform Infrared; D013237:Stereoisomerism; D014407:Tumor Cells, Cultured / Q000187:drug effects
chemical_list: D000970:Antineoplastic Agents; D002243:Carbolines; D010545:Peroxides