Faculty Publications
Permanent URI for this communityhttps://idr.nitk.ac.in/handle/123456789/18736
Publications by NITK Faculty
Browse
19 results
Search Results
Item Anti-diarrheal potential of Aegle Marmelos Corr. root bark extract in rats(2007) Vrushabendra Swamy, S.B.M.; Nataraj, K.S.; Jayaveera, K.N.; Gopkumar, P.; Nayak, S.; Kumar, G.S.; Umachigi, S.P.A study was undertaken to evaluate the effect of methanolic extract of the rootbark of Aegle marmelos Corr. (MAMC) against several experimental models of diarrhoea in rats. MAMC treated animal's showed significant inhibitory effect against castor-oil induced diarrhea and PGE2 induced enteropooling in rats. The extract also showed a significant reduction in gastrointestinal motility in the charcoal meal test in rats. The results obtained to establish the efficacy and substantiate the folkare claim as an anti-diarrhoeal agent.Item Synthesis of some new 4-styryltetrazolo[1,5-a]quinoxaline and 1-substituted-4-styryl[1,2,4]triazolo[4,3-a]quinoxaline derivatives as potent anticonvulsants(2009) Wagle, S.; Vasudeva Adhikari, A.V.; Suchetha Kumari, N.S.4-Methyltetrazolo[1,5-a]quinoxaline (3) was prepared by the azide cyclocondensation of 2-chloro-3-methylquinoxaline (2). The reaction of 3 with aromatic aldehydes furnished 4-styryltetrazolo[1,5-a]quinoxalines (4a-f). Compound 2, on treatment with hydrazine hydrate gave 2-hydrazino-3-methylquinoxaline (5). The ring closure of 5 was achieved by the reaction of orthoesters and trifluoroacetic acid to yield 4-methyl-1-(substituted)[1,2,4]triazolo[4,3-a]quinoxalines (7a-c). Further, reaction of 7a-c with different aromatic aldehydes furnished the title compounds, 4-styryl-1-(substituted)[1,2,4]triazolo[4,3-a]quinoxalines (8a-i) in good yield. In another scheme, the hydrazino compound 5 was treated with different aromatic aldehydes to yield corresponding N-arylidenehydrazino quinoxalines (6a-d). Further, the oxidative cyclization of hydrazones by nitrobenzene yielded 1-aryl-4-methyl[1,2,4]triazolo[4,3-a]quinoxalines (7d-g), which on condensation with aromatic aldehydes gave the title compounds, 1-aryl-4-styryl[1,2,4]triazolo[4,3-a]quinoxalines (8j-u). The newly synthesized compounds have been characterized by FTIR, 1H NMR, 13C NMR and mass spectral data, followed by elemental analysis. Some of the compounds were screened for in vivo anticonvulsant activity. Few of them exhibited promising results. © 2008 Elsevier Masson SAS. All rights reserved.Item Synthesis and anticonvulsant activity of some new bishydrazones derived from 3,4-dipropyloxythiophene(2009) Kulandasamy, R.; Vasudeva Adhikari, A.V.; Stables, J.P.A series of new 3,4-dipropyloxy-N2,N5-bis(substituted)thiophene-2,5-dicarbohydrazides (4-30) were synthesized from ethyl thiodiglycolate and diethyloxalate through multistep reactions. Following Dieckmann-Komppa reaction, the required precursor 3,4-dihydroxythiophene-2,5-diester (1) was prepared. This was derivatized with propyl bromide and further converted to corresponding hydrazide (3), which was finally transformed to targeted hydrazones (4-30) by conventional methods. The newly synthesized compounds were characterized using FT-IR, 1H and 13C NMR, EI-MS and elemental analyses. The anticonvulsant activity of all the title compounds was investigated against maximal electroshock induced seizures (MES) and subcutaneous pentylenetetrazole (scMET) models and their neurotoxicity was also evaluated. Some of the selected compounds were subjected to 6 Hz test in order to evaluate their uncover activities. Compound 3,4-dipropyloxy-N2,N5-bis[1-(2-thienyl)ethylidene]thiophene-2,5-dicarbohydrazide (15) has emerged as a lead in this series with less neurotoxicity. © 2009 Elsevier Masson SAS. All rights reserved.Item A new class of anticonvulsants possessing 6 Hz activity: 3,4-Dialkyloxy thiophene bishydrazones(2009) Kulandasamy, R.; Vasudeva Adhikari, A.V.; Stables, J.P.Thirty nine new 3,4-di(substituted)oxy-N2,N5-bis(substituted)thiophene-2,5-dicarbohydrazides were synthesized starting from ethyl thiodiglycolate through multi-step reactions. In the synthetic sequence, 3,4-dihydroxythiophene-2,5-diester (1) was obtained by condensing the ethyl thiodiglycolate with diethyl oxalate. It was derivatized using different alkyl halides to give disubstituted thiophene esters (2-5), which were then converted to corresponding hydrazides (6-9) following usual methods. Finally, these hydrazides, on treatment with various substituted carbonyl compounds underwent smooth condensation to yield target hydrazones (10-13). The new compounds were characterized using FT-IR, 1H NMR and 13C NMR, mass spectral and elemental analyses. The anticonvulsant activity of the title compounds was established after intraperitoneal (ip) administration in three seizure models, which include maximal electroshock (MES), subcutaneous pentylenetetrazole (scPTZ) and 6 Hz screens and their neurotoxicity was also evaluated. Compound 11f has emerged as an active compound with no neurotoxicity in this series. Also, the structure-activity relationship of the tested compounds was discussed. © 2009 Elsevier Masson SAS. All rights reserved.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 antimicrobial studies of some new pyrazole incorporated imidazole derivatives(2011) Vijesh, A.M.; Isloor, A.M.; Telkar, S.; Peethambar, S.K.; Rai, S.; Isloor, N.In the present study two series of novel imidazole derivatives containing substituted pyrazole moiety (3a-d and 5a-j) were synthesized. The first series were synthesized by the reaction of 3-aryl-1H-pyrazole-4-carbaldehyde thiosemicarbazones (2a-d) with DMAD and the second series by the reaction of 3-aryl-1H-pyrazole-4-carbaldehydes (1a-e) with 1,2-diketones (4a,b) in the presence of ammonium acetate. Structures of newly synthesized compounds were characterized by spectral studies. New compounds were screened for antifungal and antibacterial activities. Among the synthesized compounds, compound 3c was found to be potent antimicrobial agent. The acute oral toxicity study for the compound 3c was carried out and the experimental studies revealed that compound 3c is safe up to 3000 mg/kg and no death of animals were recorded. © 2011 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 and antimicrobial activity of some new pyrazole containing cyanopyridone derivatives(2012) Malladi, S.; Isloor, A.M.; Peethambar, S.K.; Ganesh, B.M.; Goud, P.S.K.A series of new 4,6-disubstituted-3-cyano-2-pyridone derivatives (4a-o) were synthesized. The structures of all target molecules (4a-o) have been confirmed by various spectral techniques and elemental analyses. The newly synthesized compounds were screened for antibacterial and antifungal activity and most of the compounds showed significant activity comparable with that of the standard drug. The results revealed that 4b, 4c, 4d, 4g, 4m, 4n and 4o showed good antibacterial activity towards all bacterial strains (Escherichia coli, Staphylococcus aureus and Pseudomonas aeruginosa) when compared to standard drug streptomycin. Amongst all the compounds, 4c showed moderate antifungal activity against Aspergillus flavus. The acute toxicity study has also been carried out for biologically active compounds and the experimental studies revealed that compounds were safe up to 2000 mg/kg and no deaths of animals were recorded.Item Synthesis and anti-inflammatory evaluation of some new 3,6-disubstituted-1, 2,4-triazolo-[3,4-b]-1,3,4-thiadiazoles bearing pyrazole moiety(2012) Malladi, S.; Isloor, A.M.; Shetty, P.; Fun, H.-K.; Telkar, S.; Mahmood, R.; Isloor, N.In the present study, a new series of 3,6-disubstituted- 1,2,4-triazolo-[3,4-b]-1,3,4-thiadiazoles (4aj) have been synthesized by condensing 3-substituted-4-amino-5- mercapto-1,2,4-triazoles (1a-b) with various 3-substitutedpyrazole- 4-carboxylic acids (3a-e) in the presence ofPOCl3. The structures of newly synthesized compounds were characterized by elemental analysis, IR, 1H NMR, 13CNMR, and mass spectroscopic studies. Structure of the compound 4b was also confirmed by recording the single crystal X-ray structure. All the synthesized compounds were screened for their anti-inflammatory activities by carrageenan induced paw edema method. Anti-inflammatory screening indicated that, compounds 4d, 4e, and 4h were found to be biologically active whereas remaining compounds showed poor antiinflammatory activity. Also molecular docking studies were also performed for compounds which showed good antiinflammatory activity. © Springer Science+Business Media, LLC 2011.Item Synthesis and evaluation of antioxidant, antimicrobial activities of new 2,4-disubstituted thiazoles(2012) Malladi, S.; Isloor, A.M.; Peethambar, S.K.; Shivananda, K.N.A new series of 2,4-disubstituted thiazole derivatives were synthesized by the reaction of various 3-aryl-1H-pyrazole-4- carbaldehyde thiosemicarbazones (2a-e) and phenacyl bromides. The compounds (3a-n) were characterized by IR, NMR, mass spectra and C, H, N analyses. All the synthesized compounds were screened for their antioxidant and antimicrobial activities. Antioxidant studies revealed that, compounds 3b, 3j and 3n showed significant scavenging activity whereas compounds 3e and 3n exhibited significant antimicrobial activity. The acute oral toxicity study for the compound 3e and 3n have revealed good safety profile till the uppermost dose (2000 mg/kg).