Structure-diversified terpenoids from Salvia prattii and their protective activity against alcoholic liver diseases

Eleven previously unreported compounds (1-11), including five diterpenoids (1-5) and six sesquiterpenoids (6-11), together with two known diterpenoids (12-13), have been isolated from the roots of Salvia prattii. Their structures were comprehensively elucidated through spectroscopic methods, and their configurations were established using computational 13C nuclear magnetic resonance and electronic circular dichroism. Compound 1 was found to be an abietane-type diterpenoid with a novel rearrangement generated from the cleavage of the C4/5 chemical bond, 20-methyl shift, and the rearrangement of the C-10 side chain. Compounds 2-3 were the third and fourth examples of arrangement seco-norabietanes with a spiro-lactone ring. We evaluated all compounds for their protective effects against alcoholic liver diseases (ALD). Compound 2 exhibited potential protective activity and hence can be used as a novel anti-ALD candidate.