Studies of molecular structure parameters of 20-piperidin-2-yl-5α-pregnan-3β,20-diol and its <i>N</i>-methyl derivative: two inhibitors of Δ<sup>24(25)</sup> sterol methyl transferase and Δ<sup>24(24′)</sup> sterol methyl reductase of <i>Trypanosoma cruzi</i>
作者:Reinaldo Atencio、Gonzalo Visbal、Sara Pekerar、Jham Papale、Julio A. Urbina
DOI:10.1107/s0108768101013234
日期:2001.10.1
more restrained, in CDCl3 solution, than (1). X-ray studies showed that maximum deviations among structural molecular parameters of (1) and (2) correspond to torsion angles along the C20-C22 bonds, leading to a different relative orientation of the N atom; a critical structural parameter for the binding properties of aza-sterols to Delta(24(25)) sterol methyl transferase. Cremer-Pople parameters of the
Azasterols as Inhibitors of Sterol 24-Methyltransferase in <i>Leishmania</i> Species and <i>Trypanosoma c</i><i>ruzi</i>
作者:Filippo Magaraci、Jimenez、Carlos Rodrigues、Juliany C. F. Rodrigues、Marina Vianna Braga、Vanessa Yardley、Kate de Luca-Fradley、Simon L. Croft、Wanderley de Souza、Luis M. Ruiz-Perez、Julio Urbina、Dolores Gonzalez Pacanowska、Ian H. Gilbert
DOI:10.1021/jm021114j
日期:2003.10.1
This paper describes the synthesis of some novel azasterols based on (20R,22xi)-5alpha-pregnan-20-(piperidin-2-yl)-3beta,20-diol. These compounds are potential inhibitors of the enzyme sterol 24-methyltransferase (24-SMT), which is a vital enzyme in the biosynthesis of ergosterol and related 24-alkyl sterols. Structure-activity studies were undertaken to understand the important features for activity against the enzyme, with the aim of increasing activity and selectivity. The compounds were evaluated for inhibition of recombinant Leishmania major 24-SMT and the effect of compounds on sterol composition and parasite proliferation. Essentially, compounds which showed good activity against the recombinant enzyme had a significant effect on the sterol composition and growth of parasites. The activity of compounds was found to be related to the basicity and stereochemical location of the nitrogen. Also, presence of an unprotected 3beta-OH seemed to be important for activity. However, some azasterols which were not good inhibitors of 24-SMT also showed antiproliferative activity, suggesting that there may be other modes of actions of these compounds.