IN-VITRO AND IN-VIVO ANTIPLASMODIAL ACTIVITY OF CRYPTOLEPINE AND RELATED ALKALOIDS FROM CRYPTOLEPIS-SANGUINOLENTA

Three different extracts and four alkaloids from the root bark of Cryp tolepis sanguinolenta have been assessed in vitro against Plasmodium f alciparum D-6 (chloroquine-sensitive strain), K-1, and W-2 (chloroquin e-resistant strains). Cryptolepine (1) and its hydrochloride (2), 11-h ydroxycryptolepine (3), and neocryptolepine (5) showed a strong antipl asmodial activity against P. falciparum chloroquine-resistant strains. Quindoline (4) was less active, The highest activity was obtained wit h compound 1. In vivo tests on infected mice showed that crytpolepine (1), when tested as hydrochloride (2), exhibited a significant chemosu ppressive effect against Plasmodium berghei yoelii and Plasmodium berg hei berghei, while 1 had the same effect against P. berghei yoelii onl y. Compounds 3 and 4 did not show activity in this in vivo test system .