[en] Isoretulinal is a new alkaloid isolated from Strychnos variabilis rootbark. It can also be easily prepared by oxydation of isoretuline. This alkaloid shows an antimitotic effect at a dose of 10 micrograms/ml on different strains of cancer cells. Moreover isoretulinal possesses an analgesic activity. However this alkaloid is sixty-fold less toxic than strychnine (intravenous acute toxicity in mice).