Ring B aromatic steroids from an endophytic fungus, Colletotrichum sp.
The new (22E,24R)-3-acetoxy-19(10-->6)-abeo-ergosta-5,7,9,22-tetraen-3beta-ol (1) and the known (22E,24R)-19(10-->6)-abeo-ergosta-5,7,9,22-tetraen-3beta-ol (2), two interesting ergosteroids with rare aromatized ring B, together with seven known derivatives, namely (22E,24R)-ergosta-5,7,22-trien-3beta-ol (3), (22E,24R)-ergosta-4,7,22-trien-3-one (4), (22E,24R)-ergosta-4,6,8(14),22-tetraen-3-one (5), (22E,24R)-5alpha,8alpha-epidioxyergosta-6,22-dien-3beta-ol (6), (22E,24R)-ergosta-7,22-dien-3beta,5alpha,6beta-triol (7), (22E,24R)-6-acetoxy-ergosta-7,22-dien-3beta,5alpha,6beta-triol (8), and (22E,24R)-3,6-diacetoxy-ergosta-7,22-dien-3beta,5alpha,6beta-triol (9), were isolated from Colletotrichum sp., an endophytic fungus isolated from Ilex canariensis from Gomera. The structures of these compounds were elucidated by detailed spectroscopic analysis, comparison with reported data, and chemical interconversion. The isolation of these metabolites not only displays a beautiful array of chemical diversity, but also gives insight into the biosynthetic interconnections. Preliminary studies showed antimicrobial activity of these compounds against the fungus Microbotryum violaceum, the alga Chlorella fusca, and the bacteria Escherichia coli and Bacillus megaterium.
Zhang
Wen
W
Research Center for Marine Drugs, School ofPharmacy, Second Military Medical University, 325 Guo-He Road, Shanghai 200433, PR China.
Draeger
Siegfried
S
Schulz
Barbara
B
Krohn
Karsten
K
D000107:Acetylation; D000900:Anti-Bacterial Agents / Q000096:biosynthesis / Q000737:chemistry / Q000494:pharmacology; D001419:Bacteria / Q000187:drug effects; D002855:Chromatography, Thin Layer; D020231:Colletotrichum / Q000737:chemistry*; D003470:Culture Media; D056890:Eukaryota / Q000187:drug effects; D005658:Fungi / Q000187:drug effects; D030017:Ilex / Q000382:microbiology; D009682:Magnetic Resonance Spectroscopy; D008826:Microbial Sensitivity Tests; D013256:Steroids / Q000096:biosynthesis / Q000737:chemistry* / Q000494:pharmacology
D000900:Anti-Bacterial Agents; D003470:Culture Media; D013256:Steroids