Four new compounds including two new sesquiterpenoid dimers, commiphoroids E (1) and F (2), a new triterpenoid (3), and a new sesquiterpenoid (4), along with three known terpenoids (5-7) were isolated from Resina Commiphora, whose structures were identified by NMR spectra, HRESIMS, and X-ray diffraction analysis. Compounds 1 and 2 both bear an O-bridge ring and feature a plausible [4 + 2] Diels-Alder cycloaddition reaction. Antimycobacterial activities show that all the tested compounds (200 μM) could inhibit the growth of both sensitive and clinically multi-drug resistant (MDR) isolated strains. In addition, cellular toxicity of the isolates against human cancer cells and THP-1 monocyte cells was examined.
Keywords: Resina Commiphora; anti-Mycobacterium tuberculosis; plant resins; terpenoids.