Synthesis and antimicrobial activity of some (3-phenyl-5-(1-phenyl-3-aryl-1H-pyrazol-4-yl)-4,5-dihydro-1H-pyrazol-1-yl)(pyridin-4-yl)methanones: new derivatives of 1,3,5-trisubstituted pyrazolines

Diverse Pharmacological Potential of different Substituted Pyrazole Derivatives

The chemistry of heterocyclic compounds has been a topic of research interest. Some five-membered heterocyclic compounds have been the subject of extensive research due to their different types of pharmacological effects. The five-membered nitrogen-containing heterocyclic compounds pyrazole, pyrazoline, and pyrazolone derivatives have a lot of interest in the fields of medical and agricultural chemistry due to their diverse spectrum of therapeutic activities. Various substituted pyrazole, pyrazoline, and pyrazolone compounds exhibited diverse pharmacological effects like Anti-microbial, anti-inflammatory, anti-tubercular, anti-fungal, anti-malarial, anti-diabetic, diuretic, anti-depressant, anticonvulsant, antioxidant, anti-leishmanial, antidiabetic, and antiviral, etc. In recent decades, the synthesis of numerous pyrazole, pyrazoline, and pyrazolone derivatives by different synthetic methods as well as research into their chemical and biological behavior have become more important. This review focuses on synthetic methods of the pyrazole, pyrazoline, and pyrazolone derivatives, which have significant biological properties and a variety of applications.

PEG-mediated synthesis, antibacterial, antifungal and antioxidant studies of some new 1,3,5-trisubstituted 2-pyrazolines

A new series of 1,3,5-trisubstituted 2-pyrazoline derivatives (3a-l) are synthesized in good to excellent yields from the corresponding chalcones (1a-h) and acid hydrazides (2a-e) in polyethylene glycol-400 (PEG-400) as a green reaction medium. The newly synthesized 2-pyrazoline derivatives are screened for their antibacterial and antifungal activity. The synthesized trisubstituted pyrazolines displayed moderate to good antibacterial and antifungal properties as compared with the standard reference penicillin and fluconazole drugs. Additionally, the antioxidant potential of the 1,3,5-trisubstituted 2-pyrazolines is evaluated by OH and DPPH assay. The 1,3,5-trisubstituted 2-pyrazolines showed good radical scavenger activity and were found as good antioxidant agents.

Synthesis of 2-Hydroxynaphthyl Pyrazolines Containing Isoniazid Moiety: A Potential Antitubercular Agent

Abstract:

The new series of pyrazolines derivatives containing isoniazid moiety were synthesized from 2-hydroxynaphthyl functionalized chalcones and isoniazid using sodium hydroxide as a base in 2- ethoxy ethanol. We evaluated their antitubercular activity against Mycobacterium tuberculosis strain (H37Rv) by Microplate Alamar Blue Assay (MABA). Some of the tested compounds 3a, 3b, and 3c, were found to have higher antitubercular activity than the selected standard drugs, whereas compounds 3d, 3e, 3i and 3j were found to have higher antitubercular activity than Streptomycin and same as that of Pyrazinamide and Ciprofloxacin, while remaining compound showed moderate activity. Whereas it is found that the disubstituted halogen compound and electron-withdrawing group on the phenyl ring are important substitutions for an increase in antitubercular activity.

Sulfamic acid catalyzed synthesis of new 3,5-[(sub)phenyl]-1H-pyrazole bearing N1-isonicotinoyl: And their pharmacological activity evaluation

A sustainable synthesis of new 3,5-[(sub)phenyl]-1H-pyrazole bearing N¹-isonicotinoyl derivatives from substituted chalcones and isoniazid by using sulfamic acid and their pharmacological activity evaluation is reported. An anti-oxidant study is performed by using DPPH assay. In vitro anti-mycobacterial activity of compounds bearing R/R' = 4-CH₃/4-F and 3-OCH₃/4-Cl showed complete inhibition (99%) at the MIC of 31 and 34 μM respectively. Antibacterial screening of compounds bearing R/R' = 4-CH₃/4-F; 4-OCH₃/4-Br; and 4-OCH₃/4-Cl has shown noticeable inhibition (27 mm) against Staphylococcus aureus. The anti-cancer bioassay demonstrated that the five compounds were active on human breast cancer cell line MCF-7; however on HeLa cervical cancer cells only two compounds are active in comparison to standard drug Doxorubicin. Higher inhibitory effects observed in this study appear to be dependent on the chloro, bromo, fluoro and methoxy functionality present on the aromatic nucleus. The structures of all the compounds are established using NMR (¹H and ¹³C), FT-IR, Mass and elemental analysis.

Synthesis, Biological Evaluation and Molecular Docking Study of Pyrazole, Pyrazoline Clubbed Pyridine as Potential Antimicrobial Agents

Introduction:

In continuation of our efforts to find new antimicrobials, herein we report the synthesis of various pyrazole, pyrazoline, and pyridine based novel bioactive heterocycles (3a-t).

Methods:

Newly synthesized compounds were analysed for their antimicrobial activity. Compounds 3c, 3h, 3i, 3k, 3n, and 3q showed significant antimicrobial activity.

Results:

Molecular docking study for the most active analogues against DNA gyrase subunit b (PDB ID: 1KZN) corroborated well with the observed antimicrobial potency exhibiting significant binding affinity.

Conclusion:

Interpretation of the chemical structures reported in this paper was based on IR, 1H NMR, 13C NMR, and mass spectral data.