A weak convulsant effect is found in the nonpolar part of the tertiary alkaloid extract of Strychnos angolensis GILG, while the polar part shows a strong muscle-relaxant activity.Five indole alkaloids have been isolated from the nonpolar part of the extract. One is the known (+)-tubotaiwine while the others are derivatives of Wieland Gumlich aldehyde (WGA): 11-methoxy-WGA, 17-0-methyl-11 methoxy-WGA, 11 -methoxy-diaboline and epi-17-0-methyl-1 I-methoxy-diaboline.Caracurine V, a tertiary dimeric alkaloid, is also found to be present in a toluene extract of bark of S. angolensis.