Botryane, noreudesmane and abietane terpenoids from the ascomycete Hypoxylon rickii. (September 2015)

• Record Type: Journal Article
• Authors: Kuhnert, Eric; Surup, Frank; Wiebach, Vincent; Bernecker, Steffen; Stadler, Marc
• Is Part Of: Phytochemistry. Volume 117(2015:Sep.)
• Page Start: 116
• Page End: 122
• Publication Date: 2015-09
• Subjects: Hypoxylon -- Xylariaceae -- Abietane -- Botryane -- Eudesmane -- Terpenes -- Secondary metabolites -- Structure elucidation -- Ascomycetes -- Biodiversity -- Endophytes -- Terpenoids -- Xylariales; Botanical chemistry -- Periodicals; Biochemistry -- Periodicals; Botany -- Periodicals; Chimie végétale -- Périodiques; 572.2
• DOI: 10.1016/j.phytochem.2015.06.002
• Languages: English
• ISSNs: 0031-9422

Abstract

Abstract : Graphical abstract: Ten terpenoids, among those seven novel natural products, were isolated from cultures of the tropical ascomycete Hypoxylon rickii (Xylariaceae). Their structures were elucidated using 2D NMR and HRESIMS. The new compounds belong to the botryane, 14-noreudesmane and abietane types. Compounds1, 2, 3, 7, and10 showed cytotoxic effects against murine cells. Highlights: Identification of Hypoxylon rickii as a prolific producer of secondary metabolites. Three new sesquiterpenoids of the botryane family were identified. Three sesquiterpenoids with 14-noreudesmane structure were identified. The first fungal abietane diterpenoid was also obtained. Abstract: In the course of our screening for new bioactive natural products, a culture of Hypoxylon rickii, a xylariaceous ascomycete collected from the Caribbean island Martinique, was identified as extraordinary prolific producer of secondary metabolites. Ten metabolites of terpenoid origin were isolated from submerged cultures of this species by preparative HPLC. Their structures were elucidated using spectral techniques including 2D NMR and HRESIMS. Three of the compounds were elucidated as new botryanes (1 –3 ) along with three known ones, i.e. (3a S )-3a, 5, 5, 8-tetramethyl-3, 3a, 4, 5-tetrahydro-1 H -cyclopenta[ de ]isochromen-1-one (4 ), (3a S, 8 R )-3a, 5, 5, 8-tetramethyl-3, 3a, 4, 5, 7, 8-hexahydro-1 H -cyclopenta[ de ]isochromen-1-one (5 ) and botryenanol (6 ). Further three new sesquiterpenoids featured a 14-noreudesmane-type skeleton and were named hypoxylan A–C (7 –9 ); the diterpenoid rickitin A (10 ) contains an abietane-type backbone. Compounds1, 2, 3, 7, and10 showed cytotoxic effects against murine cells.