Two new diterpenoids from Ballota limbata

Abstract

Two new clerodane-type diterpenoids trivially named as ballotenic acid (1) and ballodiolic acid (2) have been isolated from Ballota limbata along with three the known compounds; β-amyrin, oleanolic acid, and β-sitosterol. The structure elucidation of the new compounds was based primarily on two-dimensional (2D)-NMR techniques including correlation spectroscopy (COSY), heteronuclear multiple quantum coherence (HMQC), heteronuclear multiple bond correlation (HMBC), and nuclear Overhauser effect (NOE) experiments. Compounds 1 and 2 displayed inhibitory potential against lipoxygenase enzyme in a concentration-dependent fashion with IC50 values of 99.6 μM and 38.3 μM, respectively. © 2004 Pharmaceutical Society of Japan.