New Bergamotane Sesquiterpenoids from the Plant Endophytic Fungus Paraconiothyrium brasiliense

• Published in: Molecules (Basel, Switzerland) Switzerland), 2015-08, Vol.20 (8), p.14611-14620
• Main Authors: Guo, Zhe, Ren, Fengxia, Che, Yongsheng, Liu, Gang, Liu, Ling
• Format: Article
• Language: English
• Subjects: Ascomycota - chemistry; Carbon; Cell Line, Tumor; Cytotoxicity; Dioxoles - chemistry; Dioxoles - isolation & purification; Dioxoles - pharmacology; Drug Screening Assays, Antitumor; Endophytes - chemistry; endophytic fungus; Fungi; Humans; Magnetic Resonance Spectroscopy - methods; Metabolites; Paraconiothynium brasiliense; Piperazines - chemistry; Piperazines - isolation & purification; Piperazines - pharmacology; Sesquiterpenes - chemistry; Sesquiterpenes - isolation & purification; Sesquiterpenes - pharmacology; sesquiterpenoid; Toxicology
• ISSN: 1420-3049; 1420-3049
• DOI: 10.3390/molecules200814611

Brasilamides K-N (1-4), four new bergamotane sesquiterpenoids; with 4-oxatricyclo (3.3.1.0 (2,7))nonane (1)and 9-oxatricyclo(4.3.0.0 (4,7))nonane (2-4) skeletons; were isolated from the scale-up fermentation cultures of the plant endophytic fungus Paraconiothynium brasiliense Verkley. The previously identified sesquiterpenoids brasilamides A and C (5 and 6) were also reisolated in the current work. The structures of 1-4 were elucidated primarily by interpretation of NMR spectroscopic data. The absolute configurations of 1-3 were deduced by analogy to the co-isolated metabolites 5 and 6; whereas that of C-12 in 4 was assigned using the modified Mosher method. The cytotoxicity of all compounds against a panel of eight human tumor cell lines were assayed.