Faculty Publications
Permanent URI for this communityhttps://idr.nitk.ac.in/handle/123456789/18736
Publications by NITK Faculty
Browse
10 results
Search Results
Item Synthesis, characterization and biological activities of some new benzo[b]thiophene derivatives(2010) Isloor, A.M.; Kalluraya, B.; Pai, K.Benzo[b]thiophene molecules are found to be important tools in synthetic medicinal chemistry. They are of current interest due to their wide spectrum of pharmacological properties. In view of the biological activities of benzo[b]thiophene containing molecules, in this present research work, we propose the synthesis of some new benzo[b]thiophene derivatives such as thiadiazoles, oxadiazoles, pyrazolin & diaryl pyrazoles starting from 3-chlorobenzo[b]thiophene-2-carboxyl chloride. These newly synthesized compounds were characterized by elemental analyses, I.R, NMR and Mass spectral studies. Some of the selected compounds were screened for their antibacterial, antifungal and anti-inflammatory studies. Many of the molecules were found to be potent. © 2009 Elsevier Masson SAS. All rights reserved.Item Synthesis, characterization and biological activity of some new 1,3,4-oxadiazole bearing 2-flouro-4-methoxy phenyl moiety(2010) Chandrakantha, B.; Shetty, P.; Nambiyar, V.; Isloor, N.; Isloor, A.M.In the present study a series of new 1,3,4-oxadiazole derivatives containing 2-fluoro-4-methoxy moiety were synthesized. These newly synthesized compounds were characterized by NMR, mass spectral, IR spectral study and also by C, H, N analyses. All the newly synthesized compounds were screened for their antibacterial and antifungal studies. Antimicrobial studies revealed that compounds 4a and 4b showed significant antibacterial activity against Escherichia coli and Pseudomonas aeruginosa Compound 4i showed significant antifungal activity against C. albicans. © 2009 Elsevier Masson SAS. All rights reserved.Item Hantzsch reaction: Synthesis and characterization of some new 1,4-dihydropyridine derivatives as potent antimicrobial and antioxidant agents(2011) Vijesh, A.M.; Isloor, A.M.; Peethambar, S.K.; Shivananda, K.N.; Arulmoli, T.; Isloor, N.In the present study two new series of Hantzsch 1,4-dihydropyridine derivatives (1,4-DHPs) containing substituted pyrazole moiety (4a-f and 5a-f) were synthesized by the reaction of 3-aryl-1H-pyrazole-4-carbaldehydes with 1,3-dicarbonylcompounds (ethylacetoacetate and methylacetoacetate) and ammonium acetate. The newly synthesized compounds were characterized by IR, NMR, mass spectral study and also by C, H, N analyses. New compounds were screened for their antimicrobial activity by well plate method (zone of inhibition). Antioxidant studies of the synthesized compounds were also performed by measuring the DPPH radical scavenging assay. Compounds 4c, 4e and 4f were found to be potent antibacterial and antioxidant agents. The acute oral toxicity study for the compounds 4c, 4e and 4f were carried out and the experimental studies revealed that compounds 4c and 4e is safe up to 3000 mg/kg and no death of animals were recorded. However in compound 4f, we found mortality above 2000 mg and also significant behavioral changes in experimental animals. © 2011 Elsevier Masson SAS. All rights reserved.Item Synthesis, characterization and antimicrobial studies of some new quinoline incorporated benzimidazole derivatives(2012) Garudachari, B.; Satyanarayana, M.N.; Thippeswamy, B.; Shivakumar, C.K.; Shivananda, K.N.; Hegde, G.; Isloor, A.M.Two new series of quinoline incorporated benzimidazole derivatives (4a-i and 8a-f) were synthesized from substituted aniline and isatin through multi-step reaction. 6-substituted-4-carboxyquinolines (3a,b and 7) were synthesized by multi component one pot reactions (via Doebner reaction and Pfitzinger reaction respectively) and the targeted benzimidazole derivatives were obtained by the reaction of 6-substituted-4-carboxyquinolines (3a,b and 7) with substituted aromatic diamines in acidic media. All the newly synthesized compounds were characterized by IR, NMR mass spectral study and also by C, H, N analyses. The final compounds were screened for their in-vitro antibacterial and antifungal activity by well plate method (zone of inhibition). The results revealed that, compounds 4c, 4d, 8c and 8d showed significant antibacterial activity. The compound 8b was found to be potent antifungal agent. 4a, 8a and 8f showed moderate to good antimicrobial activity as compared to the standard drugs against all tested microbial strains. © 2012 Elsevier Masson SAS. All rights reserved.Item Design and regioselective synthesis of trifluoromethylquinolone derivatives as potent antimicrobial agents(Elsevier Masson SAS infos@masson.fr 62 rue Camille Desmoulins Issy les Moulineaux Cedex 92442, 2013) Garudachari, B.; Isloor, A.M.; Satyanarayana, M.N.; Fun, H.-K.; Pavithra, N.; Kulal, A.Three series of new trifluoromethyl substituted quinolone derivatives were synthesized (4a-f, 6a-f and 8a-f) from corresponding substituted anilines by multi-step reactions. The regioselective alkylation with different alkyl halides were carried out by approaching two different routes to get the final products in good yield. Newly synthesized compounds were characterized by spectral study and also by C, H, N analyses. Three dimensional structure of 2b and 4b were also confirmed by single crystal X-ray studies. The final compounds (4a-f, 6a-f and 8a-f) were screened for their in-vitro antibacterial and antifungal activity by well plate method (zone of inhibition). The results revealed that, compounds 4a, 6b, 6c and 8e showed significant antibacterial activity as compared to the standard drug Ciprofloxacin. The compound 8a was found to be a potent antifungal agent. © 2013 Elsevier Masson SAS. All rights reserved.Item New pyrazole derivatives containing 1,2,4-triazoles and benzoxazoles as potent antimicrobial and analgesic agents(2013) Vijesh, A.M.; Isloor, A.M.; Shetty, P.; Sundershan, S.; Fun, H.-K.Azole class of compounds are well known for their excellent therapeutic properties. Present paper describes about the synthesis of three series of new 1,2,4-triazole and benzoxazole derivatives containing substituted pyrazole moiety (11a-d, 12a-d and 13a-d). The newly synthesized compounds were characterized by spectral studies and also by C, H, N analyses. All the synthesized compounds were screened for their analgesic activity by the tail flick method. The antimicrobial activity of the new derivatives was also performed by Minimum Inhibitory Concentration (MIC) by the serial dilution method. The results revealed that the compound 11c having 2,5-dichlorothiophene substituent on pyrazole moiety and a triazole ring showed significant analgesic and antimicrobial activity. © 2012 Elsevier Masson SAS. All rights reserved.Item Synthesis of new 3-aryl-4-(3-aryl-4,5-dihydro-1H-pyrazol-5-yl)-1-phenyl-1H- pyrazole derivatives as potential antimicrobial agents(2013) Malladi, S.; Isloor, A.M.; Peethambar, S.K.; Fun, H.-K.New (E)-1-aryl-3-(3-aryl-1-phenyl-1H-pyrazol-4-yl)prop-2-en-1-ones 6 (pyrazolic chalcones) were synthesized from Claisen-Schmidt reaction of 3-aryl-1-phenylpyrazol-4-carboxaldehydes 4 with several acetophenone derivatives 5. Subsequently, the cyclocondensation reaction of chalcones 6 with phenylhydrazine in acetic acid medium afforded the new 3-aryl-4-(3-aryl-4,5- dihydro-1H-pyrazol-5-yl)-1-phenyl-1H-pyrazoles 7. The synthesized compounds were characterized by spectral studies and evaluated for their in vitro antibacterial activity against three pathogenic bacterial strains, Staphylococcus aureus, Escherichia coli, and Pseudomonas aeruginosa, and in vitro antifungal activity against three pathogenic fungal strains Aspergillus flavus, Chrysosporium keratinophilum, and Candida albicans. © 2012 Springer Science+Business Media New York.Item Synthesis and biological evaluation of novel substituted 1,3,4-thiadiazole and 2,6-di aryl substituted imidazo [2,1-b] [1,3,4] thiadiazole derivatives(Elsevier Masson s.r.l., 2014) Chandrakantha, B.; Isloor, A.M.; Shetty, P.; Fun, H.-K.; Hegde, G.A new series of N-[5-(4-(alkyl/aryl)-3-nitro-phenyl)-[1,3,4-thiadiazol-2- yl]-2,2-dimethyl-propionamide 4 (a-l) and 6-(4-Methoxy-phenyl)-2-(4-alkyl/aryl)- 3-nitro-phenyl)-Imidazo [2,1-b] [1,3,4] thiadiazole 6 (a-l) were synthesized starting from 5-(4-Fluoro-3-nitro-phenyl)-[1,3,4] thiadiazole-2-ylamine. The synthesized compounds were characterized by IR, NMR, mass spectral and elemental analysis. All the compounds were tested for antibacterial and antifungal activities. The antimicrobial activities of the compounds were assessed by well plate method (zone of inhibition). Compounds 4a, 4c and 6e, 6g displayed appreciable activity at the concentration 0.5-1.0 mg/mL.© 2013 Elsevier Masson SAS. All rights reserved.Item Click chemistry approach: Regioselective one-pot synthesis of some new 8-trifluoromethylquinoline based 1,2,3-triazoles as potent antimicrobial agents(2014) Garudachari, B.; Isloor, A.M.; Satyanarayana, M.N.; Fun, H.-K.; Hegde, G.Three series of 8-trifluoromethylquinoline based 1,2,3-triazoles derivatives (5a-c, 6a-d and 7a-c) were synthesized by multi-step reactions by click chemistry approach. Synthesized compounds were characterized by spectral studies and X-ray analysis. The final compounds were screened for their in-vitro antimicrobial activity by well plate method (zone of inhibition). Compounds 5c, 6b, 8b, 11 and 12 were found to be active against tested microbial strains. The results are summarized in Tables 5 and 6. © 2014 Elsevier Ltd. All rights reserved.Item Antitubercular and antimicrobial activity of nh4vo3 promoted 1,4-dihydropyridine incorporated 1,3,4-Trisubstituted pyrazole(Bentham Science Publishers B.V. P.O. Box 294 Bussum 1400 AG, 2017) Harikrishna, N.; Isloor, A.M.; Kulal, K.; Parish, T.; Jamalis, J.; Ghabbour, H.A.; Fun, H.-K.Background: A new series of pyrazole containing 1,4-dihydropyridine derivatives 5a-i and 6a-i were synthesized from substituted acetylated aryls and substituted phenylhydrazine by the multistep reaction. Method: The target compounds 1,4-dihydropyridine derivatives were obtained from green synthesis of 1,3-disubstituted phenyl-1H-pyrazole-4-carbaldehydes 4a-i with ethyl acetoacetate and methyl acetoacetate at higher temperatures in the presence of ammonium acetate and the catalytic amount of ammonium metavanadate (NH4VO3). The role of ammonium metavanadate was increases rate of the reaction and obtained high yields. Result: Structures of newly synthesized 1,4-dihydropyridine moiety containing pyrazole derivatives were confirmed by FT-IR, NMR and Mass spectral studies. The structure of compound 5b was confirmed by S-XRD study. Further, these compounds were tested for in-vitro antitubercular and antimicrobial studies. Compounds 5a, 5b, 5i, 6a, 6b, 6g, 6h, and 6i were found to be active against all the bacterial microorganisms. Conclusion: The above mentioned compounds have shown lowest MIC ranging between 3.12-12.5 ?g/ml against Mycobacterium tuberculosis and MIC values ranging between 7.8- 15.6 ?g/ml for Mycobacterium smegmatis, Staphylococcus aureus and Pseudomonas aeruginosa. For the control of life threatening diseases such as tuberculosis, these eight compounds may be strongly promising synthetic compounds. © 2017 Bentham Science Publishers.