title: Antitrypanosomal and cytotoxic activities of 22-Hydroxyclerosterol, a new sterol from Allexis cauliflora (Violaceae).
abstract: In the search for new antiparasitic natural compounds from the medicinal plants from Cameroon, the new 22-hydroxyclerosterol, established as such on the basis of detailed chemical and spectroscopic analysis, was isolated from the hexane extract of the stem bark of Allexis cauliflora together with the known clerosterol. 22-Hydroxyclerosterol inhibited the growth of Trypanosoma brucei brucei cells with an ED(50) value of 1.56 μM. The compound was also established as an uncompetitive inhibitor of the glycolytic enzyme PGI of T. brucei (Ki'= 3 ± 1 μM), an uncompetitive inhibitor of mammalian rabbit muscles' enzyme PyK (Ki'= 26 ± 3 μM) and a mixed inhibitor of PyK of Leishmania mexicana (Ki'= 65 ± 10 μM; Ki= 24 ± 5 μM).
authors: Laboratory of Medicinal Chemistry & Pharmacognosy, Department of Organic Chemistry, Faculty of Sciences, University of Yaoundé I, Box 812 Yaoundé, Cameroon.
authors: Yves Oscar D
authors: YO
authors: Nganso
authors: Igor Eric W
authors: IE
authors: Ngantchou
authors: Ernestine
authors: E
authors: Nkwenoua
authors: Barthelemy
authors: B
authors: Nyasse
authors: Colette
authors: C
authors: Denier
authors: Véronique
authors: V
authors: Hannert
authors: Bernd
authors: B
authors: Schneider
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