Objective(s): Histone deacetylase inhibitory and cytotoxic activities of 18 naturally occuring terpenoids (ferutinin, stylosin, tschimgine and guaiol), coumarins (umbelliprenin, farnesiferone B, conferone, feselol, ligupersin A, conferdione, conferoside) and sulfur-containing derivatives (latisulfies A-E, persicasulphides A and C) from the roots of three species of Ferula (Ferula latisecta, Fer...