New antileishmanial sesquiterpene coumarins from Ferula narthex Boiss

Two new sesquiterpene coumarins, fnarthexone (1) and fnarthexol (2), along with three known coumarin derivatives, conferol (3), conferone (4) and umbelliferone (5), were isolated from the plant Ferula narthex Boiss. The structures of the compounds 1-5 were elucidated using modern spectroscopic techniques. The structure of compound 3 was unambiguously deduced by the single-crystal X-ray diffraction technique. Compounds 1-4 were tested for in vitro leishmanicidal activity and promising results were obtained. Conferol (3) was found to be the most potent with IC50 value of 11.51 ± 0.09 μg/mL. © 2014 Phytochemical Society of Europe.