Emericellins A and B: Two sesquiterpenoids with an unprecedented tricyclo[4,4,2,1]hendecane scaffold from the liquid cultures of endophytic fungus Emericella sp. XL 029

Abstract

Two novel sesquiterpenoids with an unprecedented tricyclo[4,4,2,1]hendecane scaffold, namely emericellins A (1) and B (2) representing a new skeleton, were isolated from the liquid cultures of an endophytic fungus Emericella sp. XL 029 associated with the leaves of Panax notoginseng. Their structures and relative configurations were characterized by extensive spectroscopic methods. Compounds 1-2 displayed moderate activities against three fungal strains (Verticillium dahliae Kleb, Helminthosporium maydis, and Botryosphaeria dothidea) and three bacterial strains (Bacillus subtilis, Bacillus cereus and Escherichia coli) with MIC values of 25-50 μg/mL.

Keywords: Antimicrobial activity; Emericella sp.; Panax notoginseng; Sesquiterpenoid.