Synthesis and pharmacological evaluation of some novel 2-(5-hydroxy-5-trifluoromethyl-4,5-dihydropyrazol-1-yl)-4-(coumarin-3-yl)thiazoles

A series of novel 2-(5-hydroxy-5-trifluoromethyl-4,5-dihydropyrazol-1-yl)-4-(coumarin-3-yl)thiazoles (6) were synthesized by condensing 3-(2-bromoacetyl)coumarins (4) with various 5-hydroxy-5-trifluoromethyl-4,5-dihydropyrazol-1-thiocarboxamides (5), obtained by the reaction of thiosemicarbazide with trifluoromethyl-β-diketones. All the tested compounds displayed significant to moderate in vivo anti-inflammatory activity when compared to the standard drug indomethacin, and good broad spectrum in vitro antibacterial activity against three Gram-positive and four Gram-negative bacteria when compared with cefixime.