Synthesis and Antimicrobial Activity Evaluation of Some Novel Hydrazone, Pyrazolone, Chromenone, 2-Pyridone and 2-Pyrone Derivatives

Abstract

A cyanoacetohydrazide derivative underwent a series of reactions with different nucleophilic reagents, such as hydrazine hydrate, p-chlorobenzaldehyde and salicylaldehyde, to give the condensation products. In addition, an arylidene malononitrile was reacted with different nitrogen nucleophiles, such as hydrazine hydrate, thiocarbohydrazide and cyanoacetohydrazide, to afford the hydrazine, hydrazone and pyridin-2-one derivatives, respectively. Furthermore, a pyridin-2-one derivative was reacted with different carbon electrophiles, such as carbon disulfide, p-chlorobenzaldehyde and acetic anhydride. The antimicrobial activities of some of the compounds were examined.

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

“…Scheme ). The structure of 17 was confirmed from the study of the IR together with chemical evidence by direct comparison with an authentic sample prepared from reaction of 1,3‐diphenylpyrazole‐4‐carboxaldehyde 1 with hydrazine hydrate in refluxing ethanol (identity melting point, mixed melting point, TLC). Presumably, the formation of azine 17 could be achieved via Scheme .…”

“…The residual part was recrystallized from benzene/ethanol mixture (1:1) and found to be diheterylhydrazine 17 . The latter compound was identical in all respects (IR, mp, mixed mp, and TLC) with an authentic sample prepared by the condensation of 1,3‐diphenylpyrazole‐4‐carboxaldehyde 1 with hydrazine hydrate in ethanolic solution .…”

“…Pyrazole derivatives occupy a unique place in the medicinal chemistry due to their extensive applications, for example, antitumor , antioxidant , anti‐inflammatory , antimicrobial , and antiviral activities . Also, it has been documented that newly synthesized pyrazole derivatives known as potential anticancer agent due to their B‐Raf inhibitory activities with IC 50 values in the nano levels, for example, compounds I – IV (Fig.…”

Synthesis, Reactions and Antitumor Activity of Certain 1,3-diphenylpyrazole-4-carboxaldehyde Derivatives

“…methylene)acetohydrazide 8 [30] A mixture of 1,3-diphenylpyrazol-4carboxaldehyde 4 (2.48 g, 0.01 mole) and cyanoacetic hydrazide (1.00 g, 0.01 mole) in 25…”

One-pot synthesis of functionalized pyrazolo[3,4-c]pyrazoles by reaction of 2-cyano-N-methyl-acrylamide, aryl aldehyde, and hydrazine hydrate

“…Among them, we can mention pyrazolo-fused pyrimidines, 3 quinolines, 4 pyridines, 5 thiazoles, 6 isoquinolines, 7 imidazoles, 8 diazepines, 9 and triazines. 10 Fused pyrazoles are important classes of heterocycles with effective biological activity such as antitumor, 11 antioxidant, 2 antimicrobial, 12 antiviral, 13 and as immunostimulatory agents. 14 Moreover, some of these bicyclic heterocycles are used for treatment of autoimmune/inflammatory diseases, 1 useful for treatment of esophageal and gastrointestinal mucosa injury, 14 and potent inhibitors of hGSK-3a.…”