Synthesis of nanoparticles silica supported antimony pentachloride (SbCl5-SiO2 NPs): An efficient reagent for synthesis of 2,3,5-substituted-2H-pyrazole derivatives

Silver nanoparticles (SNPs) exhibit tremendous applications in medicine as antimicrobial agent. The use of different parts of plants for the synthesis of nanoparticles is considered as a green technology as it does not involve any harmful chemicals. In the present study, we report a rapid biosynthesis of silver nanoparticles from aqueous leaf extract of medicinal plant Allamanda cathartica. The active phytochemicals present in the plant were responsible for the quick reduction of silver ion to metallic silver nanoparticles. The reduced silver nanoparticles were characterized by using UV-Vis spectrophotometry, Scanning Electron Microscope (SEM), Energy Dispersive Analysis of X-ray (EDAX) and Atomic Force Microscopy (AFM). The spherical shaped silver nanoparticles were observed and it was found to 19-40 nm range of size. These phytosynthesized SNPs were tested for their antimicrobial activity and it analyzed by measuring the inhibitory zone. A. cathartica aqueous leaf extract of SNPs showed highest toxicity to Pseudomonas followed by Klebsiella, Bacillus and E. coli and lowest toxicity towards Proteus. In fungal species, highest inhibition zone was noted against Rhizopus followed by Curvularia, Aspergillus flavus and Aspergillus niger and minimum inhibition zone was observed against Fusarium species. These results suggest a promising potential of Indian plant-based green chemistry for production of SNPs for biomedical and nanotechnology applications.

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Microwave assisted synthesis of novel Pyrazole derivatives and their biological evaluation as anti-bacterial agents

Combinatorial Chemistry & High Throughput Screening ◽

10.2174/1386207323666201019152206 ◽

2020 ◽

Vol 23 ◽

Author(s):

Hadis Khodadad ◽

Farhad Hatamjafari ◽

Khalil Pourshamsian ◽

Babak Sadeghi

Keyword(s):

Antibacterial Activity ◽

Aromatic Aldehydes ◽

Catalytic Amount ◽

Antibacterial Activities ◽

Structural Features ◽

Biological Evaluation ◽

Aureus Strain ◽

Microwave Assisted Synthesis ◽

Pyrazole Derivatives ◽

Microwave Assisted

Aim and Objective: Microwave-assisted condensation of acetophenone 1 and aromatic aldehydes 2 gave chalcone analogs 3, which were cyclized to pyrazole derivatives 6a-f via the reaction with hydrazine hydrate and oxalic acid in the presence of the catalytic amount of acetic acid in ethanol. Materials and Methods: The structural features of the synthesized compounds were characterized by melting point, FT-IR, 1H, 13C NMR and elemental analysis. Results: The antibacterial activities of the synthesized pyrazoles was evaluated against three gram-positive bacteria such as Enterococcus durans, Staphylococcus aureus, Bacillus subtilis and two gram-negative bacteria such as Escherichia coli and Salmonella typhimurium. Conclusion: All the synthesized pyrazoles showed relatively high antibacterial activity against S. aureus strain and none of them demonstrated antibacterial activity against E. coli.

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Pyrazole Derivatives as Antitumor, Anti-Inflammatory and Antibacterial Agents

Mini-Reviews in Medicinal Chemistry ◽

10.2174/13895575113139990078 ◽

2013 ◽

Vol 13 (13) ◽

pp. 1957-1966 ◽

Cited By ~ 33

Author(s):

Jia-Jia Liu ◽

Meng-yue Zhao ◽

Xin Zhang ◽

Xin Zhao ◽

Hai-Liang Zhu

Keyword(s):

Antibacterial Agents ◽

Pyrazole Derivatives ◽

Anti Inflammatory

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Synthesis of Novel Bis-pyrazoles via Electrophilic Cyclization

Letters in Organic Chemistry ◽

10.2174/1570178615666181106155555 ◽

2019 ◽

Vol 16 (6) ◽

pp. 511-516

Author(s):

Adnan Cetin

Keyword(s):

13C Nmr ◽

Cyclization Reaction ◽

Electrophilic Cyclization ◽

Pyrazole Derivatives ◽

Spectral Analyses ◽

Mass Spectral ◽

Palladium Catalyzed ◽

Ft Ir ◽

Reaction Compound

Efficient steps towards the synthesis of novel (phenyl)(1'-aryl-1,5,5'-triphenyl[3,3'-bi-1Hpyrazol]- 4-yl)methanones 4a-e were developed. The procedure starts from 1-(4-benzoyl-1,5-diphenyl- 1H-3-pyrazolyl)-3-phenyl-2-propyn-1-one (2) which was synthesized by a palladium catalyzed crosscoupling reaction. Compound 2 reacted with various hydrazines to give (E)-(phenyl)[1,5-diphenyl-3- [3-phenyl-1-(2-arylhydrazono)-2-propyn-1-yl]-1H-4-pyrazolyl]methanones E-3a-e. The bis-pyrazole derivatives 4a-e were synthesized from electrophilic cyclization reaction of α,β-acetylenic hydrazones E-3a-e and copper(I) iodide. All synthesized compounds were characterized by FT-IR, 1H, 13C NMR and Mass spectral analyses.

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