Feruhermonins A-C: three daucane esters from the seeds of Ferula hermonis (Apiaceae)

Seventeen daucane esters have been isolated from the seeds of Ferula hermonis Boiss (Apiaceae). Three of these sesquiterpenes, 4beta-hydroxy-6alpha-benzoyl-7-daucen-9-one (1), 4beta, 8beta-dihydroxy-6alpha-benzoyl-dauc-9-ene (2), and 4beta, 9alpha-dihydroxy-6alpha-benzoyl-dauc-7-ene (4), named feruhermonins A-C, respectively, are novel natural products. The structures of these compounds were elucidated unequivocally by a series of 1D and 2D NMR analyses. Although 4beta, 8beta-dihydroxy-6alpha-(4-hydroxy-3-methoxybenzoyl)-dauc-9-ene (3) was reported previously, the complete spectroscopic data for this compound are presented here for the first time.