Isolation and biological activities of neomyrrhaol and other terpenes from the resin of Commiphora myrrha.

A new cycloartane-type triterpene named cycloartane-1 alpha,2 alpha,3 beta,25-tetraol (neomyrrhaol) (1), along with four known terpenes, sandaracopimaric acid (2), abietic acid (3), 2-methoxy-5-acetoxy-fruranogermacr-1(10)-en-6-one (4), and dehydroabietic acid (5) have been isolated from the resin of Commiphora myrrha. Their structures were elucidated by means of 1D, 2D NMR and HR-mass spectroscopy. Compounds 2 - 5 are known Compounds but not previously isolated from the resin of C. myrrha. Compounds 4 and 5 exhibited significant aromatase inhibiting activity with IC50 values at 0.2 mu M and 0.3 mu M, respectively. As shown in the MTT assay, 2, 3, 4, and 5 had inhibitory effects on HUVEC growth with IC50 values of 0.122 mu M (2), 0.125 mu M (3), 0.069 mu M (5). Compounds 1 - 5 did not inhibit contraction of the isolated uterine and did not protect HUVEC from damage induced by H2O2 at the tested concentration.