Isolation and identification of osthol from the fruits and essential oil composition of the leaves of Prangos asperula Boiss

Coumarins are bioactive secondary metabolites and could be found in the fruits of Umbelliferae. Prangos asperula Boiss. is an Iranian native plant which is found wild in many regions of Iran. Osthol, a prenylated coumarin, was isolated from the hexane extract of the fruits of P. asperula and its structure was elucidated using 1HNMR, 13CNMR, IR and MS spectra. The essential oil of the aerial parts of the plant obtained by hydrodistillation was also investigated by GC-MS. Forty-seven constituents have been identified of which 2,3,6-trimethyl benzaldehyde (18.4%), δ-3-carene (18.0%) and α-pinene (17.4%) were the main constituents of the oil.