Alkaloids and Biological Activity of Strychnos angolensis

Abstract

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–O–methyl–11–methoxy–WGA, 11–methoxy–diaboline and epi–17–O–methyl–11–methoxy–diaboline.

Caracurine V, a tertiary dimeric alkaloid, is also found to be present in a toluene extract of bark of S. angolensis.

Key Word Index

Strychnos angolensis - Loganiaceae - (+)–Tubotaiwine - 11–methoxy–Wieland–Gumlich aldehyde - 17–O–methyl–11–methoxy–Wieland–Gumlich aldehyde - 11–methoxy–diaboline - epi–17–O–methyl–11–methoxy–diaboline - Caracurine V - Indole alkaloids - Pharmacology