Synthesis and Selective Inhibitory Activity of 1-Acetyl-3,5-diphenyl-4,5-dihydro-(1<i>H</i>)-pyrazole Derivatives against Monoamine Oxidase
作者:Franco Chimenti、Adriana Bolasco、Fedele Manna、Daniela Secci、Paola Chimenti、Olivia Befani、Paola Turini、Valentina Giovannini、Bruno Mondovì、Roberto Cirilli、Francesco La Torre
DOI:10.1021/jm031042b
日期:2004.4.1
A novel series of 1-acetyl-3-(4-hydroxy- and 2,4-dihydroxyphenyl)-5-phenyl-4,5-dihydro-(1H)-pyrazole derivatives 1 - 12 have been synthesized and investigated for the ability to selectively inhibit the activity of the A and B isoforms of monoamine oxidase (MAO). The new synthesized compounds 1-12 proved to be more reversible, potent, and selective inhibitors of MAO-A than of MAO-B. Knowing that stereochemistry may be an important modulator of biological activity, we performed the semipreparative chromatographic enantioseparation of the most potent, selective, and chiral compounds, 6 and 11. The separated enantiomers were then submitted to in vitro biological evaluation while increasing their inhibitory activity and A selectivity. The (-)-6 enantiomer shows Ki(MAO-A) 2 nM and SI = 165 000, (+)-6 shows Ki(MAO-A) = 6 nM and SI = 166 666, (-)-11 shows Ki(MAO-A) = 4 nM and SI = 80 000, and (+)-11 shows Ki(MAO-A) = 7 nM and SI = 38 571.