Synthesis, characterization, and antimicrobial evaluation of carbostyril derivatives of 1H-pyrazole

Abstract

A new series of 12 derivatives of 4-pyrazolyl-N-arylquinoline-2,5-dione (4a-l) were synthesized by one pot base catalyzed cyclocondensation reaction of 1-aryl-5-chloro-3-methyl-1H-pyrazole-4-carbaldehyde (1a-c), Meldrum's acid (2) and 3-arylamino-5,5-disubstitutedcyclohex-2-enone (3a-d). All the compounds were characterized by elemental analysis, FT-IR, (1)H NMR and (13)C NMR spectral data and were screened, against six bacterial pathogens, namely Bacillus subtilis, Clostridium tetani, Streptococcus pneumoniae, Salmonella typhi, Vibrio cholerae, Escherichia coli and antifungal activity, against two fungal pathogens Aspergillus fumigatus and Candida albicans, using broth microdilution MIC (minimum inhibitory concentration) method. Some of the compounds were found to be equipotent or more potent than commercial drugs, against most of the employed strains, as evident from the screening data.

3-Acetyl-1,5-diphenyl-1H-pyrazole-4-carbonitrile

“…Owing to the various biological properties of pyrazole derivatives such as anti-cancer (Fu et al, 2010), anti-inflammatory (Bharate et al, 2008 and antimicrobial activities (Thumar & Patel, 2011), we have during the course of our medicinal chemistry research reported the synthesis and bioactivity of pyrazole derivatives (Abdel-Aziz et al, 2009, 2010AbdelWahab et al, 2009). The title compound (I) was synthesized and characterized in order to study the structure activity relationship of this class of compounds.…”

Synthesis, spectroscopic characterisation, and potential application of dyes containing a carbostyril skeleton as sensors for thiols

“…Carbostyril [2( 1H )‐quinolone] derivatives can be found among compounds of biological – antimicrobial, antitumour, antibacterial, antifungal, etc. – activity . Some of these are also used as fluorescent probes for cations and thiols .…”

Phthaloyl Dichloride–DMF Mediated Synthesis of Benzothiazole‐based 4‐Formylpyrazole Derivatives: Studies on Their Antimicrobial and Antioxidant Activities

“…The pyrazoles possessing a formyl group –CHO at the 4‐position are versatile organic synthetic intermediates for the synthesis of many heterocyclic ring systems such as pyrazolylpyrazolines , pyrazoloquinolinones , 4 H ‐pyrazolopyran , pyrazolylbenzoxazole , pyrazolothiadiazepines , pyrazolyloxazolone , pyrazolyloxadiazolines , pyrazolylthiadiazolines , imidazolylpyrazoles , pyrazolopyridines , chromenopyrazolones , and thiopyranothiazolylpyrazoles . These are equally important in the field of medicinal as well as pharmaceutical chemistry because of significant biological activities, such as anti‐inflammatory , antioxidant, antibacterial, and antifungal activities .…”