Abietane diterpenoid dimers from the roots of Salvia prionitis

Three abietane diterpenoid dimers, bisprioterones A-C (1-3), were isolated from the roots of Salvia prionitis Hance (Labiatae). Compounds 1-3 possessed two different abietane diterpenoid skeleta, which were linked via either a C-C single bond (1 and 2) or an ether bridge (3).