Thujopsene is a sesquiterpene that has been found in T. dolabrata and has diverse biological activities. It inhibits the Na+/K+-ATPase (IC50 = 25.9 µg/ml) and cytochrome P450 (CYP) isoform CYP2B6 (Ki = 0.8 µM).Thujopsene is active against Gram-positive and Gram-negative bacteria, including S. aureus, M. luteus, and S. typhimurium (MICs = 25-50 µg/ml). It inhibits antigen-induced β-hexosaminidase release from IgE-sensitized RBL-2H3 mast cells (IC50 = 25.1 µM) and is cytotoxic to A549 non-small cell lung cancer (NSCLC) cells with an LC50 value of 35.27 µg/ml. Thujopsene induces mortality in the mites D. farniae and T. putrescentiae (LC50s = 9.82 and 10.92 µg/cm2, respectively).