In the stem and roots of Anamirta cocculus the quaternary alkaloids berberine, palmatine, magnoflorine and columbamine were identified. The major tertiary alkaloid was identified as l-8-oxotetrahydropalmatine. The structure of this new alkaloid was proven by means of uv, ms, 1H nmr and 13C nmr spectrometry and chemical conversion into l-tetrahydropalmatine. © 1981, American Chemical Society. All rights reserved.