E J Gentry

Antitubercular natural products: berberine from the roots of commercial Hydrastis canadensis powder. Isolation of inactive 8-oxotetrahydrothalifendine, canadine, beta-hydrastine, and two new quinic acid esters, hycandinic acid esters-1 and -2.

L. Mitscher, L A Mitscher, D. Velde, 1998, Journal of natural products.