Unusual 5/5 fused bicyclosesquiterpenoids from Eupatorium adenophorum.

The chemical analysis on the aerial sections of Eupatorium adenophorum Spreng. resulted in the identification of four unprecedented 5/5 fused bicyclosesquiterpenoids, eupatorid A (1), and its analogues named eupatorester A-C (2 – 4) using various chromatographic techniques. Their structures were unambiguously confirmed by detailed spectroscopic investigations (including 1D, 2D-NMR and HRMS), and single crystal X-ray diffraction. The anti-inflammatory activities, in vitro tumor growth inhibitory activities and antibacterial activities of these compounds were evaluated. Four sesquiterpenoids possessing an unprecedented skeleton were isolated and characterized from the aerial parts of Eupatorium adenophorum Spreng. (Compositae) and their anti-inflammatory activities, in vitro tumor growth inhibitory activities and antibacterial activities of these compounds were evaluated. [Display omitted] • Four sesquiterpenoids possessing an unprecedented skeleton were found from Eupatorium adenophorum. • Their chemical structures were well elucidated. • Their anti-inflammatory, antibacterial and cytotoxic activities were evaluated. [ABSTRACT FROM AUTHOR]