Synthesis, Spectral Characterization, Cytotoxic, and Antimicrobial Activities of Some Novel Heterocycles Utilizing 1,3‐Diphenylpyrazole‐4‐carboxaldehyde Thiosemicarbazone

Abstract

A new series of heterocycles was synthesized via the reaction of readily obtainable 1,3‐diphenylpyrazole‐4‐carboxaldehyde thiosemicarbazone with many carbon electrophiles, for example, chloroacetic acid, chloroacetyl chloride, ethyl chloroacetate, dimethyl acetylenedicarboxylate, maleic anhydride, 3′‐nitro‐ω‐bromoacetophenone, malonic acid, acetylacetone, ethyl benzoylacetate, arylidene malononitrile, and ethyl cyanoacetate in attempt to construct imidazolidinone, thiazolidinone, thiazole, and pyrimidine derivatives. The behavior of the titled compound towards hydrazine hydrate was investigated, in addition to the ring closure under different conditions. Also, the reactions with 2‐chloroquinoline‐3‐carboxaldehyde and chromone‐3‐carboxaldehyde were discussed. The structures of all products obtained were substantiated from their analytical and spectral data. The antitumor and antimicrobial activities of the synthesized compounds were examined.

Synthesis, antiproliferative activity, and molecular docking of some N‐heterocycles bearing a pyrazole scaffold against liver and breast tumors

“…The structure of 7 was corporative by a direct comparison with an authentic sample synthesized from boiling a solution of 1,3‐diphenylpyrazole‐4‐carbaldehyde (9) with hydrazine in ethanol. [ 8 ]…”

“…The reaction mixture was evaporated under vacuum. The residue obtained was triturated with petroleum ether (60°C‐80°C) and then recrystallized from ethanol to afford the diheteryl azine, 7, namely 1,2‐bis((1,3‐diphenyl‐1H‐pyrazol‐4‐yl)methylene)hydrazine , which was established by direct comparison with an authentic sample [ 8 ] synthesized from the treatment of 1,3‐diphenylpyrazole‐4‐carbaldehyde (9) with hydrazine hydrate in boiling ethanol.…”

“…Experimental). It was interesting to investigate hydrazinolysis of the amide, 6, to afford the diheteryl azine, 7, instead of the predicted aminopyrazole derivative (8). The structure of 7 was corporative by a direct comparison with an authentic sample synthesized from boiling a solution of 1,3-diphenylpyrazole-4-carbaldehyde (9) with hydrazine in ethanol.…”

“…Considering its large pharmacological scope, substituted pyrazole skeleton is one of the worthy structure fragments in the synthetic and medicizznal chemistry, such as anti‐influenza, [ 1,2 ] antiviral, [ 3–6 ] anticancer, [ 7–12 ] anti‐inflammatory, [ 13,14 ] antitubercular, antiangiogenic, [ 15,16 ] antimicrobial, antioxidant, antidepressant, and insecticidal activities. [ 17–21 ] Moreover, the pyrazole ring is considered as an auspicious skeleton providing fair anti‐CDK2 (cyclin‐dependent kinases) behavior with selective and low toxic effects, for example, PNU‐292137 and ethyl 4‐amino‐1 H ‐pyrazole‐3‐carboxylate [ 22 ] (Figure 1).…”

Synthesis of chromenone, pyrimidinone, thiazoline, and quinolone derivatives as prospective antitumor agents

“…Design, synthesis, and pharmacological activities of pyrazole ring has been enriched in last decades, which is a core structure in various pharmaceuticals for example, antiviral, antitumor, insecticidal, plant growth regulation, anti‐biofilm, anti‐inflammatory, analgesic, and antioxidant (Figure ) . On the other hand, thiophene structure was found in various natural products and is also incorporated in many pharmacologically active skeletons .…”