title: Chaetopyranin, a benzaldehyde derivative, and other related metabolites from Chaetomium globosum, an endophytic fungus derived from the marine red alga Polysiphonia urceolata.
abstract: Cultivation of the endophytic fungus Chaetomium globosum, which was isolated from the inner tissue of the marine red alga Polysiphonia urceolata, resulted in the isolation of chaetopyranin (1), a new benzaldehyde secondary metabolite. Ten known compounds were also isolated, including two benzaldehyde congeners, 2-(2',3-epoxy-1',3'-heptadienyl)-6-hydroxy-5-(3-methyl-2-butenyl)benzaldehyde (2) and isotetrahydroauroglaucin (3), two anthraquinone derivatives, erythroglaucin (4) and parietin (5), five asperentin derivatives including asperentin (6, also known as cladosporin), 5'-hydroxy-asperentin-8-methylether (7), asperentin-8-methyl ether (8), 4'-hydroxyasperentin (9), and 5'-hydroxyasperentin (10), and the prenylated diketopiperazine congener neoechinulin A (11). The structures of these compounds were determined on the basis of their spectroscopic data analysis (1H, 13C, 1H-1H COSY, HMQC, and HMBC NMR, as well as low- and high-resolution mass experiments). To our knowledge, compound 1 represents the first example of a 2H-benzopyran derivative of marine algal-derived fungi as well as of the fungal genus Chaetomium. Each isolate was tested for its DPPH (1,1-diphenyl-2-picrylhydrazyl) radical-scavenging property. Compounds 1-4 were found to have moderate activity. Chaetopyranin (1) also exhibited moderate to weak cytotoxic activity toward several tumor cell lines.
authors.affiliation: Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, People's Republic of China.
authors.forename: Song
authors.initials: S
authors.lastname: Wang
authors.forename: Xiao-Ming
authors.initials: XM
authors.lastname: Li
authors.forename: Franka
authors.initials: F
authors.lastname: Teuscher
authors.forename: Dong-Li
authors.initials: DL
authors.lastname: Li
authors.forename: Arnulf
authors.initials: A
authors.lastname: Diesel
authors.forename: Rainer
authors.initials: R
authors.lastname: Ebel
authors.forename: Peter
authors.initials: P
authors.lastname: Proksch
authors.forename: Bin-Gui
authors.initials: BG
authors.lastname: Wang
mesh_terms: D000818:Animals; D001547:Benzaldehydes / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology; D002597:Chaetomium / Q000737:chemistry*; D004354:Drug Screening Assays, Antitumor; D008386:Marine Biology; D015394:Molecular Structure; D000461:Rhodophyta / Q000737:chemistry
chemical_list: D001547:Benzaldehydes; C516755:chaetopyranin