scholarly journals Synthesis and Pharmacological Activity of Some Pyrazolone Derivatives

Author(s):  
Faruk Alam ◽  
Ruhul Amin

A sequence of novel pyrazolone derivative was produced by the reaction of 2, 4-dinitrophenyl hydrazine (0.1 mol) and ethyl acetoacetate with benzaldehydes followed by hydrazine hydrate and  finally treated with secondary amine and formaldehyde and the synthesized compounds were characterized by their physical properties (M.P and TLC) and UV, IR, 1HNMR, Mass spectroscopic studies respectively. The entire synthesized complex was tested for their anthelmintic, antimicrobial and haemostatic activity against gram-positive and gram-negative strains of bacteria and Eudrilus eugenia and human venous blood. The antimicrobial activity of synthesized pyrazolone derivatives was assessed by agar cup method. All the synthesized complexes were screened for the antimicrobial, athelmintic and haemostatic activity against some gram (+ve), Gram(-ve) organisms, Eudrilus eugenia and human venous blood. The complexes exhibited reasonable to upright activity when compared with the standard one.

2021 ◽  
Vol 18 ◽  
Author(s):  
Srinu Bhoomandla ◽  
Rambabu Gundla ◽  
Phani Raja Kanuparthy

: Novel pyrazole tagged pyridine derivatives 5a-n synthesized starting from 3-cyano-4-trifluoromethyl-6- thiophenyl 2(1H) pyridone 1. Compound 1 on hydrolysis followed by decarboxylation resulted in 4-trifluoro-methyl-6- thiophenyl 2(1H)pyridone 2. Compound 2 treated with POCl3 to get 2- chloro-4-trifluoromethyl-6- thiophenyl pyridine 3 further reaction with hydrazine hydrate, which resulted in the formation of compound 4. Compound 4 on reaction with different substituted 1,3-diketones in ethanol reflux condition to afford pyrazole substituted pyridine derivatives 5a-n. All derivatives were tested against Gram-positive and Gram-negative bacterial strains and different Candida strains by well diffusion method, compounds 5k and 5l showed significant activity. The binding mode of 5k and 5l also studied by molecular docking studies.


2019 ◽  
Vol 35 (2) ◽  
pp. 822-828
Author(s):  
Cong Tien Nguyen ◽  
Dao Thi Hong Dinh ◽  
Thin Van Nguyen ◽  
Giang Duc Le ◽  
Hien Cao Nguyen

4-Chlorobenzylidene-2-methyl-(4H)-oxazol-5-one, which were prepared from 4-chlorobenzaldehyde and acetylglycine in reaction with hydrazine hydrate in ethanol gave 1-amino-4-(4-chlorobenzylidene)-2-methyl-1H-imidazolin-5(4H)-one. However, treatment of 4-chlorobenzylidene-2-methyl-(4H)-oxazol-5-one with hydrazine hydrate in pyridine yielded 3-(4-chlorophenyl)propanohydrazide. Reaction of 1-amino-4-(4-chlorobenzylidene)-2-methyl-1H-imidazolin-5(4H)-one with aromatic aldehydes gave eight corresponding Schiff’s bases namely 1-arylideneamino-4-(4-chlorobenzylidene)-2-methyl-1H-imidazolin-5(4H)-ones. The structure of the 3-(4-chlorophenyl)propanohydrazide and the imidazoline-5-one compounds was confirmed by IR, 1H-NMR and MS spectral data. The Schiff’s bases were tested for antimicrobial activities against several strains of Gram-positive, Gram-negative bacteria, molds and yeasts.


2018 ◽  
Vol 28 (2) ◽  
pp. 73
Author(s):  
Ghazwan Ali Salman

A series of new 3-Acetyl N-Methyl-2-quinolones oxadiazoles derivatives were synthesized by reaction of 3-acetyl-4-hydroxy-1-methylquinolin-2(1H)-one 3 with ethylbromoacetate to produce compounds 4. The hydrazinolysis of compound 4 with hydrazine hydrate afforded hydrazide compounds 5. New Schiff bases 6 were obtained by condensation of compound 5 with different aryl aldehydes. The last step involves refluxing compound 6 with acetic anhydrides to give the corresponding 3-acetyl-N-methylquinolin-2-one oxadiazoles 7. All the synthesized compounds were characterized on the basis of FT-IR, 1H-NMR and 13C-NMR. The synthesized compounds have been evaluated for antimicrobial activity against Gram-positive and Gram-negative bacteria. Among sixteen synthesized novel compounds, in which five compounds (7a, 7b, 7c, 7e, 7g) ex-hibited promising Antimicrobial activity as compared to Trimethoprim (100μg/ml).


Author(s):  
Singh Gurvinder ◽  
Singh Prabhsimran ◽  
Dhawan R. K.

In order to develop new antimicrobial agents, a series of 3-formyl indole based Schiff bases were synthesized by reacting 3-formyl indole(indole-3-carboxaldehyde) with substituted aniline taking ethanol as solvent. The reaction was carried in the presence of small amount of p-toluene sulphonic acid as catalyst.All the synthesized compounds were characterized by IR, 1H-NMR spectral analysis. All the synthesized compounds were evaluated for antimicrobial activity against two gram positive bacterial strains (B. subtilisand S. aureus) and two gram negative bacterial strains (P. aeruginosaand E. coli) and one fungal strain (C. albicans). All the synthesized compounds were found to have moderate to good antimicrobial activity. The  standard drug amoxicillin, fluconazole were used for antimicrobial activity. Among the synthesized compounds, the maximum antimicrobial activity was shown by compounds GS04, GS07, GS08 and GS10.


2019 ◽  
Vol 10 ◽  
pp. 1864-1872
Author(s):  
Prof. Teodora P. Popova

The effect of ionized aqueous solutions (anolytes and catholyte) in the processing of fruits (cherries, morellos, and strawberries) for decontamination has been tested. Freshly prepared analytes and catholyte without the addition of salts were used, as well as stored for 7 months anolytes, prepared with 0.5% NaCl and a combination of 0.5% NaCl and 0.5% Na2CO3. The anolyte prepared with a combination of 0.5% NaCl and 0.5% Na2CO3, as well as the anolyte obtained with 0.5% NaCl, exhibit high antimicrobial activity against the surface microflora of strawberries, cherries, and sour cherries. They inactivate E. coli for 15 minutes. The other species of the fam. Enterobacteriaceae were also affected to the maximum extent, as is the total number of microorganisms, especially in cherries and sour cherries. Even stored for 7 months, they largely retain their antimicrobial properties. Anolyte and catholyte, obtained without the addition of salts, showed a lower effect on the total number of microorganisms, but had a significant effect on Gram-negative bacteria, and especially with regard to the sanitary indicative E. coli.


2020 ◽  
Author(s):  
Nusrat Abedin ◽  
Abdullah Hamed A Alshehri ◽  
Ali M A Almughrbi ◽  
Olivia Moore ◽  
Sheikh Alyza ◽  
...  

Antimicrobial resistance (AMR) has become one of the more serious threats to the global health. The emergence of bacteria resistant to antimicrobial substances decreases the potencies of current antibiotics. Consequently, there is an urgent and growing need for the developing of new classes of antibiotics. Three prepared novel iron complexes have a broad-spectrum antimicrobial activity with minimum bactericidal concentration (MBC) values ranging from 3.5 to 10 mM and 3.5 to 40 mM against Gram-positive and Gram-negative bacteria with antimicrobial resistance phenotype, respectively. Time-kill studies and quantification of the extracellular DNA confirmed the bacteriolytic mode of action of the iron-halide compounds. Additionally, the novel complexes showed significant antibiofilm activity against the tested pathogenic bacterial strains at concentrations lower than the MBC. The cytotoxic effect of the complexes on different mammalian cell lines show sub-cytotoxic values at concentrations lower than the minimum bactericidal concentrations.


2018 ◽  
Vol 69 (4) ◽  
pp. 815-822 ◽  
Author(s):  
Lucia Pintilie ◽  
Amalia Stefaniu ◽  
Alina Ioana Nicu ◽  
Maria Maganu ◽  
Miron Teodor Caproiu

A new series of fluoroquinolone compounds have been obtained by Gould-Jacobs method. The compounds have been characterized by physic-chemical methods (elemental analysis, FTIR, NMR, UV-Vis) and by antimicrobial activity against Gram-positive and Gram-negative microorganisms. For the synthesized compounds have been performed calculations of characteristics and molecular properties, using Spartan�14 Software from Wavefunction, Inc. Irvine, CA. and molecular docking studies using CLC Drug Discovery Workbench 2.4 software, to identify and visualize the most likely interaction ligand (fluoroquinolone) with the receptor protein.


2020 ◽  
Vol 17 ◽  
Author(s):  
Ravi Bansal ◽  
Pradeep K. Soni ◽  
Neha Gupta ◽  
Sameer S. Bhagyawant ◽  
Anand K. Halve

Aims: In this article we have developed an eco-friendly one-pot multi-component reaction methodology was employed for the green synthesis of functionalized pyrazole derivatives viz cyclo-condensation of aromatic aldehydes, ethyl acetoacetate and phenyl hydrazine and/or hydrazine hydrate in the presence of cetyltrimethylammoniumbromide (CTAB) at 90°C temperature in aqueous medium. Method: In the present protocol we developed a green method for the synthesis of functionalized pyrazole derivatives through one-pot, multi-component cyclo-condensation of aromatic aldehydes, phenyl hydrazine or hydrazine hydrate and ethyl acetoacetate using cetyltrimethylammoniumbromide (CTAB) as a catalyst in water as solvent. Our methodology confers advantages such as short reaction time, atom economy, purification of product without using column chromatographic and hazardous solvent. The reaction is being catalyzed by cetyltrimethylammoniumbromide (CTAB) and thus products are formed under the green reaction conditions. Results: Initially the reaction of benzaldehyde and phenylhydrazine with ethyl acetoacetate was carried out in water at room temperature in the absence of the catalyst; no product was obtained after 24 h (Table 1 entry 1). When the reaction was carried out using L-proline as catalyst in ethanol at 70°C the yield of product was 20. Conclusion: This research not only provides a green and efficient method for the synthesis of sulfinic esters but also shows new applications of electrochemistry in organic synthesis. We consider that this green and efficient synthetic protocol used to prepare sulfinic esters will have good applications in future. In conclusion, we have developed successfully a green and efficient one-pot multi-component methodology for the synthesis of substituted pyrazoles using CTAB as a catalyst in water as solvent with excellent yields. Purifications of compounds were achieved without the use of traditional chromatographic procedures. This methodology has advantages of operational simplicity, clean reaction profiles and relatively broad scope which make it more attractive for the diversity oriented synthesis of these heterocyclic libraries. In this methodology we suggest the further alternative possibility for formation of substituted pyrazoles. The compound 7h can be used as an anticancer drug in pharma industry.


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