scholarly journals Antimicrobial Evaluation and Synthesis of Some Phenylpyrazolo benzothiazolo quinoxaline Derivatives

2009 ◽  
Vol 6 (3) ◽  
pp. 866-870
Author(s):  
CH. Sridevi ◽  
K. Balaji ◽  
A. Naidu ◽  
R. Sudhakaran

2,3-Diphenyl quinoxaline(SI)was fused with 2-amino benzothiazoles(SII)by a methylene bridge, which was then allowed for acetylation. The acetylated product (SIV) was made to react with different aromatic aldehydes to give chalcones(SV1-SV5). Chalcones refluxed with substituted acid hydrazides to afford different phenyl pyrazolo benzothiazolo quinoxaline derivatives(SVI1-SVI15). The structure of chalcones and phenyl pyrazolo benzothiazolo quinoxaline derivatives were confirmed by M.P, TLC and spectral data. All the synthesized compounds were screened for their antimicrobial activities.

2010 ◽  
Vol 7 (1) ◽  
pp. 234-238 ◽  
Author(s):  
C. H. Sridevi ◽  
K. Balaji ◽  
A. Naidu ◽  
R. Sudhakaran

2,3-Diphenyl quinoxaline (NI) was fused with benzimidazole (NII) by a methylene bridge, which was then allowed for acetylation. The acetylated product (NIV) was made to react with different aromatic aldehydes to give chalcones (NV1-NV5). Chalcones refluxed with substituted acid hydrazides to afford different phenyl pyrazolo benzimidazole quinoxaline derivatives (NVI 1-NVI 15). The structure of chalcones and phenyl pyrazolo benzimidazole quinoxaline derivatives were confirmed by m.p, TLC and spectral data. All the synthesized compounds were screened for their antihistaminic activity. Compounds NVI-3, NVI-12, NVI-13, NVI-14 and NVI-15 were shown good % protection of antihistamic activity.


Molecules ◽  
2019 ◽  
Vol 24 (21) ◽  
pp. 4009 ◽  
Author(s):  
Alsaedi ◽  
Farghaly ◽  
Shaaban

A novel series of pyrazolo[1,5-a]pyrimidine ring systems containing phenylsulfonyl moiety have been synthesized via the reaction of 2-(phenylsulfonyl)-1-(4-(phenylsulfonyl) phenyl)ethan-1-one, 2-benzenesulfonyl-1-(4-benzenesulfonyl-phenyl)-3-dimethylamino-propenone and 3-(dimethylamino)-1-(4-(phenylsulfonyl)phenyl)prop-2-en-1-one each with various substituted aminoazopyrazole derivatives in one pot reaction strategy. The proposed structure as well as the mechanism of their reactions were discussed and proved with all possible spectral data. The results of antimicrobial activities of the new sulfone derivatives revealed that several derivatives showed activity exceeding the activity of reference drug. Contrary to expectations, we found that derivatives containing one sulfone group are more effective against all bacteria and fungi used than those contain two sulfone groups.


Author(s):  
Jayanta Sarma ◽  
Gurvinder Singh ◽  
Mukta Gupta ◽  
Reena Gupta ◽  
Bhupinder Kapoor

Objective: The synthesis of novel benzimidazole-hydrazone derivatives has been carried out based on the previous findings that both these pharmacophores possess potent antimicrobial activities. The antibacterial properties of synthesized derivatives were screened against both Gram-positive and Gram-negative bacteria.Methods: O-phenylenediamine on condensation with substituted aromatic acids in polyphosphoric acid gave benzimidazole nucleus which on reaction with ethyl chloroacetate and hydrazine hydrate in two different steps resulted in the formation of substituted acetohydrazides. The targeted compounds 6a-l were synthesized by reaction of substituted acetohydrazides with aromatic aldehydes and screened for their antibacterial potential by cup-plate method.Results: The synthesized benzimidazole-hydrazones exhibited moderate to strong antibacterial activities against Staphylococcus aureus, Bacillus subtilis, Escherichia coli, and Pseudomonas aeruginosa. The compounds 6a-6f were found to be most effective against S. aureus, E. coli, and P. aeruginosa. Among all the synthesized compounds, the zone of inhibition of 6f in highest concentration, i.e., 100 μg/ml were found to be >31 mm against all the stains of bacteria.Conclusion: The antibacterial results revealed that the synthetized derivatives have significant antimicrobial properties and further structure activity relationship studies may develop more potent and less toxic molecules.


2004 ◽  
Vol 72 (2) ◽  
pp. 175-185 ◽  
Author(s):  
E. R. EI-Bendary ◽  
F. E. Goda ◽  
A. R. Maarouf ◽  
F. A. Badria

A series of quinoxaline derivatives has been synthesized by reacting 3-hydrazinoquinoxalines 1a,b with many bifunctional reagents. Reaction of 1a,b with chloroacetyl chloride and ethyl chloroacetate afforded 1-chloromethyl[1,2,4]tnazoIo[4,3-a]quinoxalines 2a,b and dihydro[1,2,4]triazino[4,3-a]quinoxalin-2-ones 3a,b respectively. Condensation of 1a,b with ethyl acetoacetate and acetylacetone yielded 2-quinoxalinylhydrazonobutanoates 4a,b and 2-quinoxalinylhydrazono-2-pentanones 5a,b respectively. Cyclization of 5a,b gave 3,5-dimethylpyrazolylquinoxalines 6a,b. Moreover, reaction of compounds 2a,b with N-phenyl piperazine derivatives afforded 4-(4-Arylpiperazin-1-yl)-1-[(4-arylpiperazin-1-yl) methyl)]triazoloquinoxalines 7a−e. The prepared compounds were screened for in vitro antibacterial and antifungal activities. None of the tested compounds showed significant activity towards Pseudomonas aeruginosa. However, remarkable activities were noticed for compounds 5a and 5b against Eschenchia coli. Staphylococcus aureus and Candida albicans. Compounds 6a and 6b lacked any antimicrobial activities against the tested microorganisms.


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.


2011 ◽  
Vol 8 (2) ◽  
pp. 924-930 ◽  
Author(s):  
CH. Sridevi ◽  
K. Balaji ◽  
A. Naidu

Indoloquinoxalin was fused with 2,3 diphenyl quinoxaline by a methylene bridge which was then allowed for acetylation. The acetylated product was made to react with different aromatic aldehydes to give chalcones. Chalcones refluxed with substituted acid hydrazides to afford different indoloquinoxaline pyrazolines. The structure of chalcones and indoloquinoxaline pyrazolines were confirmed byM.P,TLCand spectral data. All the synthesized compounds were screened for their antioxidant, anti-inflammatory and antihistamic activities.


Polymers ◽  
2021 ◽  
Vol 13 (11) ◽  
pp. 1859
Author(s):  
Periyan Durairaju ◽  
Chinnasamy Umarani ◽  
Govindasami Periyasami ◽  
Perumberkandigai Adikesavan Vivekanand ◽  
Mostafizur Rahaman

Herein we report new multiblock chalcone conjugate phthalimide and naphthalimide functionalized copolymers with a topologically novel architecture synthesis using nucleophilic substitution and polycondensation methodology. The structures of the synthesized novolacs were elucidated on the basis of their spectroscopic analysis including FTIR, 1H NMR, and 13C NMR spectroscopy. Further, the number-average and weight-average molecular weights of the novolac polymers were determined by gel permeation chromatography (GPC). We examined the solubility of the synthesized polymers in various organic solvents including CHCl3, CH3CN, THF, H2O, CH3OH, DMSO, and DMF and found they are insoluble in both methanol and water. The novolac polymers were evaluated for their photophysical properties and microbial activities. The investigation of the antimicrobial activities of these polymers reveals significant antimicrobial activity against the pathogens E. coli, S. aureus, C. albicans, and A. niger.


2014 ◽  
Vol 79 (9) ◽  
pp. 1059-1073 ◽  
Author(s):  
Salem Mounir ◽  
Magda Marzouk ◽  
Naglaa Mahmoud

Various fused pyrimidine such as furo[2,3-d]pyrimidine, triazolo[1,5-a]pyrimidine, tetrazolo[1,5-a]pyrimidine were synthesized from the reactions of thioxopyrimidine-6(1H)-ones with ethyl chloroacetate (under different reaction conditions), thiourea, and sodium nitrite. Pyrimidine thiones reacted with POCl3/PCl5 to give the chloro derivatives which reacted with sodium azide, and thiourea to give the tetrazolo[1,5-c]pyrimidine, pyrimido pyrimidine. Thioxopyrimidine-6(1H)-ones reacted with benzyl amine to give pyrrolo[2,3-d]pyrimidinethione. Theoretical calculation using MIDO/3, Fukui indices and the heat of formation of some compounds were carried out. The pharmacological and antimicrobial activities of some of the synthesized products were also evaluated.


2017 ◽  
Vol 5 (1) ◽  
pp. 17 ◽  
Author(s):  
V. Manikandan ◽  
S. Balaji ◽  
R. Senbagam ◽  
R. Vijayakumar ◽  
M. Rajarajan ◽  
...  

About ten substituted (E)-N'-1-(substituted benzylidene) benzohydrazides have been synthesized. They are analyzed by their analytical, ultra violet (UV), Fourier transform-IR (FT-IR) and nuclear magnetic resonance (NMR) spectral data and evaluated by antimicrobial activities such antibacterial and antifungal activities.


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