Divyesh Patel

Synthesis and biological evaluation of some thiazolidinones as antimicrobial agents.

A novel series of thiazolidinone derivatives namely 4-(4-dimethylamino-6-{4-[5-(4-ethylpiperazin-1-ylmethyl)-4-oxo-2-phenylthiazolidin-3-yl]-phenylamino}-[1,3,5]triazin-2-yloxy)-1-methyl-1H-quinolin-2-one have been synthesized from the key intermediate 4-[4-(4-aminophenylamino)-6-dimethylamino-[1,3,5]triazin-2-yloxy]-1-methyl-1H-quinolin-2-one (7). Condensation reaction of compound 7 with different aldehyde derivatives were performed to obtain Schiff base derivatives, which after cyclization gave thiazolidinones and finally they were reacted with N-ethylpiperazine to get target compounds. The newly synthesized compounds were evaluated for their antimicrobial activity against eight bacterial strains (Staphylococcus aureus, Bacillus cereus, Escherichia coli, Pseudomonas aeruginosa, Klebsiella pneumoniae, Salmonella typhi, Proteus vulgaris, Shigella flexneri) and four fungal strains (Aspergillus niger, Candida albicans, Aspergillus fumigatus, Aspergillus clavatus).

In vitro antimicrobial assessment of coumarin-based s -triazinyl piperazines

A series of 1,3,5-triazine derivatives that contain aniline, coumarins (4-hydroxy coumarin and 7-hydroxy-4-methyl coumarin) and different piperazine moieties as substituent on the carbon atoms of the triazine ring have been synthesized by a simple and efficient synthetic protocol. Comparative studies were performed on above series, which were synthesized with conventional and microwave heating methods. The microwave method was observed to be more beneficial as it provides an increase in yield and 90–95% reduction time. All the synthesized compounds were then examined for their efficacy against two Gram −ve bacteria (Escherichia coli and Pseudomonas aeruginosa), two Gram +ve bacteria (Staphylococcus aureus and Bacillus subtilis) and two fungal species (Candida albicans and Aspergillus niger) with an intent to overcome multiple drug resistance to the pathogenic strains. All the synthesized compounds were structurally elucidated by IR, 1H NMR, 13C NMR and elemental analysis.

In vitro antimicrobial and antimycobacterial activity of some chalcones and their derivatives

In this study, novel series of chalcone derivatives, namely, 4-[4-(3-phenyl-acryloyl)-phenylamino]-chromen-2-one (5a–k) have been synthesized from the intermediate 4-(4-acetyl-phenylamino)-chromen-2-one (4). Cyclization reaction of chalcone (5a–k) with hydrazine hydrate, guanidine nitrate, and malononitrile gives the corresponding 4-[4-(1-acetyl-5-phenyl-4,5-dihydro-1H-pyrazol-3-yl)-phenylamino]-chromen-2-one (6a–k), 4-[4-(2-amino-6-phenyl-pyrimidin-4-yl)-phenylamino]-chromen-2-one (7a–k), and 2-amino-6-[4-(2-oxo-2H-chromen-4-ylamino)-phenyl]-4-phenyl-nicotinonitrile (8a–k) derivatives were synthesized. The newly synthesized compounds were evaluated for their antimycobacterial activity and antimicrobial activity against eight bacteria (S.aureus, B. cereus, E. coli, P. aeruginosa, K. pneumoniae, S. typhi, P. vulgaris, and S. flexneri) and four fungi (A. niger, C. albicans, A. fumigatus, and A. clavatus).

Synthesis of 3-{4-[4-dimethylamino-6-(4-methyl-2-oxo-2H-chromen-7-yloxy)-[1,3,5]triazin-2-ylamino]-phenyl}-2-phenyl-5-(4-pyridin-2-yl-piperazin-1-ylmethyl)-thiazolidin-4-one and their biological evaluation

A novel series of thiazolidinone derivatives namely 3-{4-[4-dimethylamino-6-(4-methyl-2-oxo-2H-chromen-7-yloxy)-[1,3,5]triazin-2-ylamino]-phenyl}-2-phenyl-5-(4-pyridin-2-yl-piperazin-1-ylmethyl)-thiazolidin-4-one have been synthesized from the intermediate 7-[4-(4-amino-phenylamino)-6-dimethylamino-[1,3,5]triazin-2-yloxy]-4-methyl-chromen-2-one (7). Condensation reaction of compound 7 with different aldehyde derivatives were performed to give Schiff base derivatives, which after cyclization gave thiazolidinones and they were incorporated with 1-pyridin-2-yl-piperazine to get target compounds. The newly synthesized compounds were evaluated for their antimicrobial activity against eight bacteria (S.aureus, B. cereus, E. coli, P. aeruginosa, K. pneumoniae, S. typhi, P. vulgaris, and S. flexneria) and four fungi (A. niger, C. albicans, A. fumigatus, and A. clavatus).

Synthesis of s-triazine-based thiazolidinones as antimicrobial agents.

5 A novel series of thiazolidinone derivatives, namely 4-{4-dimethylamino-6-[4-oxo- 2-phenyl-5-(4-pyridin-2-yl-piperazin-1-ylmethyl)-thiazolidin-3-yl]-[1,3,5]-triazin-2-yloxy}- 1-methyl-1H-quinolin-2-ones, have been synthesized from the key intermediate 4-(4-amino- 6-dimethylamino-[1,3,5]-triazin-2-yloxy)-1-methyl-1H-quinolin-2-one (). Compound 5 was condensed with various aldehydes to give Schiff base derivatives, which after cyclization gave thiazolidinones that were linked with 1-pyridin-2-yl-piperazine to obtain the target compounds. The newly synthesized compounds were evaluated for their antimicrobial activity against eight bacteria (Staphylococcus aureus, Bacillus cereus, Escherichia coli, Pseudomonas aeruginosa, Klebsiella pneumoniae, Salmonella typhi, Proteus vulgaris, Shigella flexneri) and four fungi (Aspergillus niger, Candida albicans, Aspergillus fumigatus, Aspergillus clavatus)

Microwave assisted synthesis and in vitro antimicrobial assessment of quinolone based s-triazines

Abstract A series of 1,3,5-triazine derivatives that contain aniline, 4-hydroxy-N-methylquinolone and different piperazine and piperidine moieties as substituents on the carbon atoms of the triazine ring has been synthesized by a simple and efficient synthetic protocol. Comparative studies were performed on the compounds, which were synthesized with conventional and microwave heating methods. The microwave method was observed to be more beneficial as it provides an increase in yield and 90%–95% reduction time. The antimicrobial activity of the compounds was tested against seven bacteria (Staphylococcus aureus, Bacillus cereus, Escherichia coli, Pseudomonas aeruginosa, Klebsiella pneumonia, Salmonella typhi, Proteus vulgaris) and two fungi (Aspergillus niger, Candida albicans). The results indicate that some of the novel s-triazines have noteworthy activity in MIC and agar diffusion tests.