Indole Alkaloids. XX. Isolation and Structural Elucidation of Four Minor Alkaloids from Voacanga Chalotiana Pierre Ex Stapf

A further study of Voacanga chalotiana Pierre ex Stapf has led to the isolation of two known indole alkaloids: polyneuridine [2] and akuammidine [3], and of two new oxygenated derivatives of voachalotine [1]: voachalotine oxindole [4] and 21(?)-hydroxyvoachalotine [5].