From Tabernaemontana chippii root bark, forty-five alkaloids were isolated;
thirty-four were fully characterized by means of their spectral data andor co-tlc; eight alkaloids
were new, four of them being 3-hydroxy derivatives of known dimeric voacamine type alkaloids.
Most of the twenty-six known alkaloids belonged to the corynanthean, ibogan, or bisindole
classes. The structures of eleven other alkaloids-all minor-were only partially elucidated,
most of them being new alkaloids. All the dimeric alkaloids were shown to possess strong antimicrobial
activity against gram-positive bacteria and moderate to weak activity against gramnegative
bacteria