Synthesis and Characterization of Novel 2-(1,2,3-Triazol-4-yl)-4,5-dihydro-1H-pyrazol-1-yl)thiazoles and 2-(4,5-Dihydro-1H-pyrazol-1-yl)-4-(1H-1,2,3-triazol-4-yl)thiazoles

Abstract

Reactions of 1-(5-methyl)-1H-1,2,3-triazol-4-yl)ethan-1-ones and benzaldehydes in ethanol under basic conditions gave the corresponding chalcones. Reactions of the chalcones combined with thiosemicarbazide in dry ethanol containing sodium hydroxide afforded the corresponding pyrazolin-N-thioamides. Reactions of the synthesized pyrazolin-N-thioamides and several ketones (namely, ethyl 2-chloro-3-oxobutanoate, 2-bromoacetylbenzofuran, and hydrazonoyl chloride) gave the corresponding novel 2-(1,2,3-triazol-4-yl)-4,5-dihydro-1H-pyrazol-1-yl)thiazoles in high yields (77–90%). Additionally, 2-(4,5-dihydro-1H-pyrazol-1-yl)-4-(1H-1,2,3-triazol-4-yl)thiazoles were obtained in high yields (84–87%) from reactions with N-pyrazoline-thioamides and 4-bromoacetyl-1,2,3-triazoles under basic conditions. The structures of six of the newly synthesized heterocycles were confirmed by X-ray crystallography.

(2Z,5Z)-5-((3-(Benzofuran-2-yl)-1-phenyl-1H-pyrazol-4-yl)methylene)-2-((4-methoxyphenyl)imino)-3-phenylthiazolidin-4-one

“…The current study reports the synthesis of a new heterocycle, containing benzofuran, thiazolidin-4-one, and pyrazole moieties, using a simple procedure. This is in continuation of the investigation into the synthesis and structure elucidation of a range of new heterocyclic compounds reported in recent years [18][19][20][21][22].…”

(E)-1-(1-(Benzofuran-2-yl)ethylidene)-2-(2,4,6-trichlorophenyl)hydrazine

“…Recently, we have explored the synthesis and structure elucidation of a range of new heterocycles [19][20][21]. Hybrid molecules, which contain different moieties with biological activities, have the potential for higher potency and lower harmful effects [22].…”

1-(2,4-Dinitrophenyl)-2-((Z)-2-((E)-4-fluorobenzylidene)-3,4-dihydronaphthalen-1(2H)-ylidene)hydrazine

“…Recently, the synthesis and structure elucidation of a range of new heterocycles have been explored [18][19][20]. The title compound was synthesized in continuation of this work.…”