Antibacterial mono- and sesquiterpene esters of benzoic acids from Iranian propolis

BACKGROUND: Propolis (bee glue) has been used as a remedy since ancient times. Propolis from unexplored regions attracts the attention of scientists in the search for new bioactive molecules. RESULTS: From Iranian propolis from the Isfahan province, five individual components were isolated: the prenylated coumarin suberosin 1, and four terpene esters: tschimgin (bornyl p-hydroxybenzoate) 2, tschimganin (bornyl vanillate) 3, ferutinin (ferutinol p-hydroxybenzoate) 4, and tefernin (ferutinol vanillate) 5. All of them were found for the first time in propolis. Compounds 2 - 5 demonstrated activity against Staphylococcus aureus. CONCLUSIONS: The results of the present study are consistent with the idea that propolis from unexplored regions is a promising source of biologically active compounds.