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1
Content available remote Synthesis, Pharmacological and Insect Antifeedant Activities of some 3-(2-naphthyl)-5-(substituted phenyl)-4,5-dihydroisoxazoles
Thirunarayanan G., Sathiyendiran V.
International Letters of Chemistry, Physics and Astronomy
|
2015
|
Vol. 49
1--14
EN
Totally thirty one 3,5-substituted aryl 4,5-dihydro isoxazole derivatives including 3-(2-naphthyl)-5-(substituted phenyl)-4,5-dihydroisoxazole have been synthesized by fly-ash:H2SO4 catalyzed cyclization of hydroxylamine hydrochloride and aryl chalcones under solvent-free conditions. The yields of the isoxazoles are more than 94%. The synthesized isoxazole were characterized by their physical constants and spectral data. The antimicrobial, antioxidant and insect antifeedant activities of the synthesized isoxazoles have been evaluated using a variety of bacterial and fungal species, DPPH radical scavenging and castor-leaf disc bioassay of 4th instar larvae Achoea Janata L methods.
2
Content available remote Effect of Substituents on Phenazine Derivatives by Spectral Studies
Thirunarayanan G., Muthuvel I., Sathiyendiran V.
International Letters of Chemistry, Physics and Astronomy
|
2015
|
Vol. 48
114--122
EN
A series of eleven substituted dipyrido[3,2-a; 2′,3′-c]phenazine derivatives have been synthesized and examined their purities by literature method. The infrared and 13C NMR spectral data of prepared phenazines were correlated with Hammett substituent constants, F and R parameters using single and multi-regression analysis. From the results of statistical analysis, the effect of substituents on the infrared frequencies (ν, cm-1) and 13C nmr chemical shifts(δ, ppm) has been studied.
3
Content available remote Bio-Potent (5-chloro-2-thienyl)-3-(substituted Phenyl) bicyclo[2.2.1]heptane-2-yl Methanone Derivatives
Thirunarayanan G.
International Letters of Chemistry, Physics and Astronomy
|
2015
|
Vol. 42
1--12
EN
A series of (5-chloro-2-thienyl)(3-(substituted phenyl) bicyclo [2.2.1] hept-5-en-2-yl) methanones have been synthesized by fly-ash catalyzed [4+2] cycloaddition Diels-Alder reaction of cyclopentadiene and 5-chloro-2-thienyl chalcones under cooling conditions. The yields of the methanones are more than 60%. The synthesized (5-chloro-2-thienyl)(3-(substituted phenyl) bicyclo [2.2.1] hept-5-en-2-yl) methanones are characterized by their physical constants and spectral data. The antimicrobial, antioxidant and insect antifeedant activities of synthesized methanones have been studied using their respective bacterial, fungal strains, DPPH radical scavenging activity and Dethler’s leaf-discs bioassay method.
4
Content available Synthesis, spectral correlations and biological activities of some (E)-[4-(substituted benzylidene amino)phenyl] (phenyl) methanones
Mayavel P., Thirumurthy K., Dineshkumar S., Thirunarayanan G.
International Letters of Chemistry, Physics and Astronomy
|
2014
|
Vol. 20, iss. 2
145--159
EN
A series of Schiff’s bases have been synthesized by fly-ash:p-toluenesulfonic acid (fly-ash:PTS) catalyzed microwave assisted oxidative coupling of arylamines and substituted benzaldehydes under solvent-free condition. The synthesized Schiff’s bases are characterized by their physical constants, analytical and spectroscopic data. The group frequencies of imines such as IR (v, cm–1) and NMR (δ, ppm) spectral data was correlated with Hammett substituent constants, F and R parameters using single and multi-linear regression analysis. The antimicrobial activities of these Schiff’s bases have been studied using Bauer-Kirby method.
5
Content available Structure parameter correlation of some quinoxaline derivatives through IR and 13C NMR spectra
Thirunarayanan G., Muthuvel I., Sathiyendiran V.
International Letters of Chemistry, Physics and Astronomy
|
2014
|
Vol. 19, iss. 2
198--207
EN
A series of 6-substituted quanoxaline derivatives have been synthesized and examined their purities by literature method. The infrared and 13>/Sup>C NMR spectral data of these quinoxalines were correlated with Hammett substituent constants, F and R parameters using single and multi-regression analysis. From the results of statistical analysis, the effect of substituents on the spectral frequencies has been studied.
6
Content available Spectral QSAR and QPR study of some (E)-4-(((2 hydroxy-6-(substituted phenyl)-1,6 dihydropyrimidin 4-yl)methyl)diazenyl)benzoic acid derivatives
Thirunarayanan G., Sekar K. G.
International Letters of Chemistry, Physics and Astronomy
|
2014
|
Vol. 17, iss. 1
10--20
EN
A series of titled compounds were synthesized and recorded the infrared and NMR spectra. The assigned spectral group frequencies were correlated with Hammett substituent constants, F and R parameter. From the statistical analysis results, the effect of substituents on the spectral group frequencies has been studied.
7
Content available Spectral correlations in some substituted styryl (E)-4-((2-oxopropyl) diazenyl) benzoic acids
Sathiyendiran V., Sekar K. G., Thirunarayanan G., Arulkumaran R., Sundararajan R., Kamalakkannan D., Suresh R., Manikanadan V., Vijayakumar R., Vanangamudi G.
International Letters of Chemistry, Physics and Astronomy
|
2014
|
Vol. 11, iss. 1
33-43
EN
A series of titled compounds were prepared and analyzed their purities by literature method. The infrared and NMR spectral group frequencies of the compounds were assigned and correlated with Hammett substituent constants, F and R constants using single and multi linear regression analysis. From the results of statistical analysis, the effect of substituents on the above spectral frequencies was discussed.
8
Content available Spectral correlation analysis of Hammett substituent constants and biological activities of some (E)-1-(4-phenoxyphenyl)-3-phenylprop-2-en-1-ones
Kalyanasundaram N., Sakthinathan S. P., Suresh R., Kamalakkannan D., Joseph S. J., Vanangamudi G., Thirunarayanan G.
International Letters of Chemistry, Physics and Astronomy
|
2014
|
Vol. 9
23--47
EN
A series of aryl chalcones have been synthesized from 4-phenoxyacetophonone with various substituted benzaldehydes. The purity of all chalcones has been checked using their physical constants and spectral data. These spectral data have been correlated with Hammett substituent constants and F and R parameters using single and multi-linear regression analysis. From the results of statistical analysis, the effect of substituents on the above spectral data has been studied. The single parameter correlation with few Hammett constants and F and R parameters gave satisfactory correlation coefficients whereas all multiple correlations gave satisfactory correlation coefficients with Resonance, Field and Swain-Lupton’s parameters. The antimicrobial activities of all chalcones have been studied using Bauer-Kirby method.
9
Content available Spectral correlation analysis and antimicrobial activities of some 2,4-dimethoxy phenyl chalcones
Joseph S. J., Arulkumaran R., Kamalakkannan D., Sakthinathan S. P., Sundararajan R., Suresh R., Vijayakumar S., Ranganathan K., Kalyanasundaram N., Vanangamudi G., Thirunarayanan G.
International Letters of Chemistry, Physics and Astronomy
|
2014
|
Vol. 4
48--65
EN
A series of 2,4-dimethoxy phenyl chalcones have been synthesized by Crossed-Aldol condensation of 2,4-dimethoxy phenyl and various substituted benzaldehydes. The purities of these chalcones have been checked by their physical constants, UV, IR, NMR and MASS spectral data. The spectral data of these chalcones have been correlated with Hammett sigma constants, F and R parameters using single and multi-linear regression analysis. From the results of statistical analysis, the effects of substituents on the spectral group frequencies have been discussed. The anti-microbial activities of these chalcones have been evaluated using Bauer-Kirby method.
10
Content available Solvent-free synthesis and assessment of substituent effects from IR & NMR spectra of some substituted benzylidene-5-ethyl-1,3,4-thiadiazole-2-amines
Thirunarayanan G.
International Letters of Chemistry, Physics and Astronomy
|
2014
|
Vol. 5
89--98
EN
A series containing ten titled compounds were synthesized by SiO2:H3PO4 catalyzed solvent-free condensation of substituted benzaldehydes and 2-amino-5-ethyl-1,3,4-thiadiazole under microwave irradiation. The yields of prepared amines are more than 90 %. The synthesized amines were characterized by their physical constants and spectroscopic data reported in literature earlier for known compounds. The assigned spectral group frequencies such as infrared νC=N, C-S-C, N-N (cm-1) and NMR chemical shifts (δ, ppm) of CH, C=N have been correlated with Hammett substituent constants, F and R parameters using single and multi-linear regression analysis. From the results of statistical analyses, the effects of substituent on the above spectral data have been discussed.
11
Content available Pharmacological and insect antifeedant activities of some 3-(2,4-dichloro-5-fluorophenyl)-5-(substituted phenyl)-4,5-dihydro-1H-pyrazole-1-carbothioamides
Thirunarayanan G.
International Letters of Chemistry, Physics and Astronomy
|
2014
|
Vol. 18
47--56
EN
A series containing twelve titled compounds were synthesized by solvent-free method and their purities were examined by literature procedure. These compounds were subjected to study the pharmacological effects such as antibacterial, antifungal and antioxidant activities and the insect antifeedant activities using Bauer-Kirby disc diffusion method with their bacterial and fungal strains, DPPH radical scavenging and leaf disc bio-assay method with 4th instar larvae Achoea janata L.
12
Content available NMR Spectral correlations in some Tröger’s bases
Thirunarayanan G, Suresh M.
International Letters of Chemistry, Physics and Astronomy
|
2014
|
Vol. 4
1--11
EN
Some Tröger’s bases have been synthesised from substituted anilines and paraformaldehyde in presence of Lewis acid catalyst such as anhydrous AlCl3, through electrophilic substitution reaction. The purities of these Tröger’s bases have been checked by their physical constants and spectroscopic data published earlier in the literature. The NMR chemical shift (δ, ppm) of methylene protons and carbon were assigned. The assigned methylene protons and carbon chemical shifts (δ, ppm) of synthesised Tröger’s bases have been correlated with Hammett substituent constants, F and R parameters using single and multi-regression analyses. From the results of statistical analyses, the effects of substituent on methylene protons and carbon were discussed.
13
Content available Microwave assisted sulphated titania catalyzed aldol condensation: Synthesis of some (E) 3-(2-naphthyl)-1-(substituted phenyl)-2-propen-1-ones under solvent-free conditions
Janaki P., Sekar K. G., Thirunarayanan G.
International Letters of Chemistry, Physics and Astronomy
|
2014
|
Vol. 9
16--22
EN
A series of titled chalcones were synthesized by aldol condensation between 2-naphthaldehyde and various substituted acetophenones using solid acidic solid sulphated titania catalyst under microwave irradiation. The yields of these chalcones are more than 90 %. The synthesized chalcones are characterized by their physical constants, analytical and spectroscopic data.
14
Content available IR and NMR spectral studies of some 4-(6-methoxy-2-naphthyl)-5,6-dihydro-6-(substituted phenyl)-4H-1,3-oxazine-2-amines: Assessment of substituent effects
Thirunarayanan G.
International Letters of Chemistry, Physics and Astronomy
|
2014
|
Vol. 4
109--116
EN
A series containing thirteen title compounds were synthesized and recorded IR and NMR spectra. The infrared νNH, C=N(cm-1)stretches, 1H NMR δNH, 13C NMR δC=N(ppm) chemical shifts of synthesized oxazine amines were assigned and correlated with Hammett substituent constants, F and R parameters. From the results of statistical analyses, the effect of substituents on the above spectral frequencies can be discussed.
15
Content available IR and 1H NMR spectral studies of some 2-Amino-4-isopropyl-6-methoxy-N-phenylpyrimidine-5-carboxamides: Assessment of substituent effects
Arulkumaran R., Sundararajan R., Manikandan V., Sathiyendiran V., Pazhamalai S., Thirunarayanan G.
International Letters of Chemistry, Physics and Astronomy
|
2014
|
Vol. 19, iss. 1
15--25
EN
A series of 2-Amino-4-isopropyl-6-methoxy-N-phenylpyrimidine-5-carboxamide compounds have been synthesized from various substituted dithioacetal and guanidine. The purities of these compounds were checked by their physical constants, UV, IR, NMR and MASS spectral data. The IR and 1HNMR spectral data of these compounds have been correlated with Hammett sigma constants, F and R parameters using single and multi-linear regression analysis. From the results of statistical analysis, the effects of substituents on the spectral group frequencies have been discussed.
16
Content available Insect antifeedant potent unsaturated 1,3-oxazine-2-amines
Thirunarayanan G., Renuka V., Sekar K.G., Lakshmanan K., Anbarasu K.
International Letters of Chemistry, Physics and Astronomy
|
2014
|
Vol. 4
66--81
EN
Insect antifeedant activities of some halo substituted aryl 1,3-oxazine-2-amines have been measured using 4th instar larvae Achoea Janata L by castor leaf discs-Dethler’s method. The highly halo substituted oxazine amines have shown good insect antifeedant activities. The 1,3-oxazine amines have been synthesised by greener method by solvent-free cyclization of aryl enones with urea under microwave irradiation. The yields of the oxazines were more than 80 %. The synthesised oxazines were characterized by their physical constants, analytical and spectroscopic data.
17
Content available Insect antifeedant potent halogen substituted phenyl chalcones
Sundararajan R., Arulkumaran R., Vijayakumar S., Kamalakkannan D., Suresh R., John J. S., Ranganathan K., Sakthinathan S. P, Vanangamudi G., Thirunarayanan G.
International Letters of Chemistry, Physics and Astronomy
|
2014
|
Vol. 1
67-73
EN
Some 2′,3′,4′-trichlorophenyl chalcones [(E)-1-(2,3,4-trichlorophenyl)-3-(substituted phenyl)-2-propen-1-ones] have been synthesised using sulfated Titania catalyzed solvent-free aldol condensation between 2,3,4-trichloroacetophenone and substituted benzaldehydes. The purities of synthesised chalcones were checked by their analytical, physical and spectroscopic data reported in literature. The insect antifeedant activities of these chalcones have been studied using 4th instar larvae Achoea Janata L by castor leaf disc bio-assay method. The chloro substituted chalcones shows significant insect antifeedant activity.
18
Content available Infrared and NMR spectral Hammett correlations in 4-(2-naphthyl)-5,6-dihydro-6-(substituted phenyl)-4H-1,3-oxazine-2-amines
Thirunarayanan G., Pazhamalai S., Sekar K. G.
International Letters of Chemistry, Physics and Astronomy
|
2014
|
Vol. 8
38--46
EN
A series containing ten titled compounds have been synthesised and recorded the IR and NMR spectra. From the spectra the infrared νNH, C=N, C-O-C stretches, NMR chemical shifts of (δ, ppm) NH and C=N were assigned and correlated with Hammett substituent constants, F and R parameters using single regression analysis. From the results, the effects of substituent on the above spectral frequencies were discussed.
19
Content available Infrared and ¹³C NMR spectral studies of some aryl hydrazides: Assessment of substituent effects
Thirunarayanan G., Sekar G. K., Lakshmi Narayanan R.
International Letters of Chemistry, Physics and Astronomy
|
2014
|
Vol. 13, iss. 1
88-94
EN
A series of some aryl hydrazides have been synthesized. These hydrazides purities were analyzed by physical constants and spectral data. The assigned spectral group frequencies were correlated with Hammett substituent constants and Swain-Lupton parameters using single and multi-linear regression analysis. From the results of statistical analysis, the effect of substituents on the spectral group frequencies has been discussed.
20
Content available Hammett spectral correlations in some aryl 1,3-oxazine-4-thione derivatives
Thirunarayanan G., Sekar K. G.
International Letters of Chemistry, Physics and Astronomy
|
2014
|
Vol. 17, iss. 2
193--200
EN
A series of some aryl 1,3-oxazine-4-thione derivatives have been synthesized by 1-methyl imidazole catalyzed three component one pot synthetic method in room temperature. The purities of these thiones were studied by their physical constants and spectroscopic data. The infrared and 13C NMR spectral data of CN and CS were correlated with Hammett substituent constants, F and R parameters using single and multi-linear regression analysis. From the results of statistical analysis, the effect of substituent on the spectral data was studied.
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