Polyketide-Terpene Hybrid Metabolites from an Endolichenic Fungus Pestalotiopsis sp. (16th May 2017)

• Record Type: Journal Article
• Authors: Yuan, Chao; Ding, Gang; Wang, Hai-Ying; Guo, Yu-Hua; Shang, Hai; Ma, Xiao-Jun; Zou, Zhong-Mei
• Other Names: Xu Lijian Academic Editor.
• Is Part Of: BioMed research international. Volume 2017(2017)
• Publication Date: 2017-05-16
• Subjects: Medicine -- Periodicals; Biology -- Periodicals; Biotechnology -- Periodicals; Life sciences -- Periodicals; 610.5
• DOI: 10.1155/2017/6961928
• Languages: English
• ISSNs: 2314-6133

Abstract

Abstract : Five new polyketide-terpene hybrid metabolites (1 –5 ) with highly functionalized groups, together with six known derivatives (6 –11 ), were isolated from the endolichenic fungus Pestalotiopsis sp. Their structures were elucidated by extensive NMR experiments including 1 H, 13 C, HMQC, COSY, and HMBC. The relative configurations of the new compounds were determined by analysis of coupling constants and ROESY correlations. The absolute configurations especially the secondary alcohol at C-15 in 1 and secondary alcohol at C-14 in 5 were established via the CD experiments of the in situ formed [Rh2 (OCOCF3 )4 ] complex with the acetonide derivatives. These compounds were tested for their inhibition activity against six plant pathogens. Compounds 1 and 5 exhibited pronounced efficiency against Fusarium oxysporum, and compounds 5 and 6 potently inhibited Fusarium gramineum with MIC value of 8 µ g/mL, which revealed the plausible ecological role of endolichenic fungus in providing chemical protection for its host lichen in the fungus-plant relationship. The biosynthetic pathway of compounds 1 –11 was postulated for the first time, which paved the way for its further biosynthesis research.