Synthesis and Biological Evaluation of Novel 4-indolyl-5-phenyl(indolyl)- 1,2-dihydropyrazol-3-ones as Glycogen Synthase Kinase-3β (GSK-3β) Inhibitors

Nineteen novel 4-indolyl-5-phenyl(indolyl)-1,2-dihydropyrazol-3-ones were synthesized and evaluated for their GSK-3β inhibitory activity. Half of the tested compounds showed moderate GSK-3β inhibitory activity. Preliminary structure-activity relationships were discussed, which showed that the presence of 3,4,5-trimethoxy group on the benezene ring enhanced potency while the existence of an electron-withdrawing group at the 4-position of the benezene ring deceased activity. Compounds 11c and 14, the most potent compounds with IC50 values of 9.28 and 8.98 μM, respectively, would be promising candidates for further development of novel GSK-3β inhibitors.