Chemical constituents from the roots of Ranunculus ternatus and their inhibitory effects on Mycobacterium tuberculosis.

Two new benzophenones, methyl (R)-3-[2-(3,4-dihydroxybenzoyl)-4,5-dihydroxyphenyl]-2-hydroxypropanoate (1) and n-butyl (R)-3-[2-(3,4-dihydroxybenzoyl)-4,5-dihydroxyphenyl]-2-hydroxypropanoate (2), were isolated from the roots of Ranunculus ternatus along with the two known compounds vanillic acid (3) and gallic acid (4). Their structures were elucidated by physical and spectroscopic analysis. In addition, compound 1 exhibited obvious activity against tuberculosis, while the activity of a 1:1 mixture of compound 1 plus 4 is better than that of 1 alone.