title: Antiprotozoal activities of heterocyclic-substituted xanthones from the marine-derived fungus Chaetomium sp.
abstract: Investigations of the marine-derived fungus Chaetomium sp. led to the isolation of the new natural products chaetoxanthones A, B, and C (1-3). Compounds 1 and 2 are substituted with a dioxane/tetrahydropyran moiety rarely found in natural products. Compound 3 was identified as a chlorinated xanthone substituted with a tetrahydropyran ring. The configurational analysis of these compounds employed CD spectroscopy, modified Mosher's method, and selective NOE gradient measurements. Compound 2 showed selective activity against Plasmodium falciparum with an IC50 value of 0.5 microg/mL without being cytotoxic toward cultured eukaryotic cells. Compound 3 displayed a moderate activity against Trypanosoma cruzi with an IC50 value of 1.5 microg/mL.
authors.affiliation: Institute for Pharmaceutical Biology, University of Bonn, Nussallee 6, 53115 Bonn, Germany.
authors.forename: Alexander
authors.initials: A
authors.lastname: Pontius
authors.forename: Anja
authors.initials: A
authors.lastname: Krick
authors.forename: Stefan
authors.initials: S
authors.lastname: Kehraus
authors.forename: Reto
authors.initials: R
authors.lastname: Brun
authors.forename: Gabriele M
authors.initials: GM
authors.lastname: König
mesh_terms: D000818:Animals; D000981:Antiprotozoal Agents / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology*; D001410:Bacillus megaterium / Q000187:drug effects; D002597:Chaetomium; D002708:Chlorella / Q000187:drug effects; D004354:Drug Screening Assays, Antitumor; D004926:Escherichia coli / Q000187:drug effects; D007893:Leishmania donovani / Q000187:drug effects; D008386:Marine Biology; D008826:Microbial Sensitivity Tests; D008958:Models, Molecular; D021261:Parasitic Sensitivity Tests; D010963:Plasmodium falciparum / Q000187:drug effects; D051381:Rats; D014349:Trypanosoma cruzi / Q000187:drug effects; D044004:Xanthones / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology*
chemical_list: D000981:Antiprotozoal Agents; D044004:Xanthones; C532693:chaetoxanthone A; C532694:chaetoxanthone B; C532695:chaetoxanthone C; C512872:xanthonol