Bisabolane, cyclonerane, and harziane derivatives from the marine-alga-endophytic fungus Trichoderma asperellum cf44-2

• Published in: Phytochemistry (Oxford) 2018-08, Vol.152, p.45-52
• Main Authors: Song, Yin-Ping, Liu, Xiang-Hong, Shi, Zhen-Zhen, Miao, Feng-Ping, Fang, Sheng-Tao, Ji, Nai-Yun
• Format: Article
• Language: English
• Subjects: Bisabolane; Cyclonerane; Harziane; Moniliaceae; Terpene; Trichoderma asperellum
• ISSN: 0031-9422; 1873-3700
• DOI: 10.1016/j.phytochem.2018.04.017

Three undescribed bisabolane derivatives, trichaspin, trichaspsides A and B, three undescribed cyclonerane sesquiterpenes, 9-cycloneren-3,7,11-triol, 11-cycloneren-3,7,10-triol, and 7,10-epoxycycloneran-3,11,12-triol, and one undescribed harziane diterpene, 11-hydroxy-9-harzien-3-one, were obtained from the culture of Trichoderma asperellum cf44-2, an endophyte of the marine brown alga Sargassum sp. Their structures and relative configurations were assigned by analysis of 1D/2D NMR and MS data, and their absolute configurations were established by ECD or specific optical rotation data. Trichaspin features an unprecedented ethylated bisabolane skeleton, while trichaspsides A and B represent the first aminoglycosides of bisabolane and norbisabolane sesquiterpenes, respectively. Nine of the compounds were evaluated for inhibition of five marine-derived pathogenic bacteria and toxicity to a marine zooplankton. Seven undescribed terpenes, involving bisabolane, cyclonerane, and harziane derivatives, were discovered from Trichoderma asperellum cf44-2, an algal endophyte. [Display omitted] •Seven undescribed terpenes were characterised and identified from Trichoderma asperellum cf44-2.•Trichaspin features an unprecedented ethylated bisabolane skeleton.•Trichaspside A represents the first aminoglycoside of bisabolane sesquiterpenes.•Trichaspside B represents the first aminoglycoside of norbisabolane sesquiterpenes.