Synthesis and Characterization Novel Derivatives of Pyrazole-4-Carbaldehyde Containing Coumarin Group

Coumarin or 1,2-benzopyrone is a secondary metabolite found in some plants and microorganisms. Researchers have focused on the synthesis of coumarin-based hybrid compounds with multiple pharmacological activities as therapeutic agents. These hybrid molecules; It stands out as a drug candidate that can be used for the treatment of diseases such as cancer, Alzheimer's, cardiovascular diseases, metabolic syndromes, AIDS and malaria. In this study, it was aimed to synthesize novel pyrazole derivatives containing coumarin group and to identfy their structures. For this, firstly, our starting compound 1-(benzo[d]thiazol-2-yl)-3-(2-oxo-2H-chromen-3-yl)-1H-pyrazole-4-carbaldehyde (M-1) was synthesized. Afterwards, the obtained M-1 compound was interacted with various nucleophilic reagents (hydrazines, thiosemicarbazides, o-phenylene diamine and aryl amines) and as a result of advanced reactions, new coumarin-pyrazole derivatives were synthesized (M-2―M-18). In addition, various chalcone derivatives (M-19―M-22) were obtained from the Claisen-Schmidt Condensation of M-1 with different acetophenones. New pyrazole-coumarin derivatives (M-23―M-26) were synthesized from the cyclization reactions of the obtained chalcone derivatives with different hydrazines and o-phenylene diamine. On the other hand, 4-(hydroxymethyl) pyrazole derivative (M-27) was synthesized by reduction of pyrazole-4-carbaldehyde compound and finally a 4-chloromethyl pyrazole derivative (M-28) was obtained from this compound. The structures of the synthesized compounds were characterized by FT-IR, 1H-NMR, 13C-NMR and mass spectra.