title: Ohioensins and pallidisetins: novel cytotoxic agents from the moss Polytrichum pallidisetum.
abstract: Bioassay-directed fractionation of an EtOH extract of the moss Polytrichum pallidisetum (Polytrichaceae) led to the isolation of three novel benzonaphthoxanthenones, 1-O-methylohioensin B [6], 1-O-methyldihydroohioensin B [7] and 1,14-di-O-methyldihydroohioensin B [8], and two novel cinnamoyl bibenzyls, pallidisetin A [9] and pallidisetin B [10]. Their structures and relative stereochemistry were established by spectral analyses and chemical correlation. Compounds 6-10 exhibited cytotoxic activity against the human tumor cell lines RPMI-7951 melanoma and U-251 glioblastoma multiforme. These two types of compounds could hypothetically be derived from cinnamic acid and bibenzyls through different biogenetic pathways.
authors.affiliation: Division of Medicinal Chemistry and Pharmacognosy, College of Pharmacy, Ohio State University, Columbus 43210.
authors.forename: G Q
authors.initials: GQ
authors.lastname: Zheng
authors.forename: D K
authors.initials: DK
authors.lastname: Ho
authors.forename: P J
authors.initials: PJ
authors.lastname: Elder
authors.forename: R E
authors.initials: RE
authors.lastname: Stephens
authors.forename: C E
authors.initials: CE
authors.lastname: Cottrell
authors.forename: J M
authors.initials: JM
authors.lastname: Cassady
mesh_terms: D000818:Animals; D000972:Antineoplastic Agents, Phytogenic / Q000302:isolation & purification* / Q000494:pharmacology; D001572:Benzofurans / Q000302:isolation & purification* / Q000494:pharmacology; D002934:Cinnamates / Q000302:isolation & purification* / Q000494:pharmacology; D004354:Drug Screening Assays, Antitumor; D006801:Humans; D007941:Leukemia P388 / Q000188:drug therapy; D009682:Magnetic Resonance Spectroscopy; D051379:Mice; D008968:Molecular Conformation; D008970:Molecular Weight; D010946:Plants, Medicinal / Q000737:chemistry*; D011083:Polycyclic Compounds / Q000302:isolation & purification* / Q000494:pharmacology; D013055:Spectrophotometry, Infrared; D013056:Spectrophotometry, Ultraviolet; D014407:Tumor Cells, Cultured; D014966:Xanthenes / Q000302:isolation & purification* / Q000494:pharmacology
chemical_list: D000972:Antineoplastic Agents, Phytogenic; D001572:Benzofurans; D002934:Cinnamates; D011083:Polycyclic Compounds; D014966:Xanthenes