Showing papers by "Badiadka Narayana published in 2006"
TL;DR: In this article, the synthesis, crystal growth and non-linear optical properties of new chalcone derivatives are reported, including 4-propyloxy and 4-butoxy benzaldehydes.
131 citations
TL;DR: In this paper, two bis-chalcone derivatives, 1,5-[di(4-methoxyphenyl)]penta-1,4-dien-3-one and 1, 5-[di (4-chlorophenyl]penta]-1, 4-dimethylhexyl hexylhexylhexylon, were synthesized using Z-scan technique using 7ns laser pulses at 532nm.
90 citations
TL;DR: Four novel compounds prepared by treating 7-chloro-5-(2-fluorophenyl)-1,3-dihydro-2H-1,4-benzodiazepine-2-thione with various aromatic acid hydrazides exhibited excellent anticonvulsant activity in comparison with standard drug, diazepam.
52 citations
TL;DR: In this article, a selective and rapid spectrophotometric method for the determination of nitrite is presented, which is based on the reaction of nitrites with p-nitroaniline in acid medium to form diazonium ion, coupled with ethoxyethylenemaleic ester or ethylcyanoacetate in basic medium to create azo dyes.
Abstract: A selective and rapid spectrophotometric method for the determination of nitrite is presented. It is based on the reaction of nitrite with p-nitroaniline in acid medium to form diazonium ion, which is coupled with ethoxyethylenemaleic ester or ethylcyanoacetate in basic medium to form azo dyes, showing absorption maxima at 439 and 465 nm respectively. The method obeys Beer's law in the concentration range of 0.5-16 µg mL-1 of nitrite with ethoxyethylenemaleic ester and 0.2-18 µg mL-1 of nitrite with ethylcyanoacetate. The molar absorptivity and Sandell's sensitivity of p-nitroaniline-ethoxyethylenemaleic ester and p-nitroaniline-ethylcyanoacetate azo dyes are 5.04 X 104 L mol-1cm-1, 0.98 X 10-2 µg cm-2 and 1.21 X 104 L mol-1 cm-1, 0.98 X 10-2 µg cm-2 respectively. The optimum reaction conditions and other analytical parameters were evaluated. The method was successfully applied to the determination of nitrite in various water samples and soil samples.
23 citations
Journal Article•
TL;DR: In this paper, a simple and sensitive spectrophotometric method has been developed for the determination of arsenic using variamine blue as a chromogenic reagent, which is based on the reaction of arsenic(III) with potassium iodate in acid medium to liberate iodine, which oxidizes variamines blue to form a violet coloured species having an absorption maximum at 556 nm.
Abstract: A simple and sensitive spectrophotometric method has been developed for the determination of arsenic using variamine blue as a chromogenic reagent. The method is based on the reaction of arsenic(III) with potassium iodate in acid medium to liberate iodine, which oxidizes variamine blue to form a violet coloured species having an absorption maximum at 556 nm. Beer's law is obeyed in the range 0.2-14 μg mL -1 of As(III). The molar absorptivity, Sandell's sensitivity, detection limit and quantitation limit were found to be 1.43×10 4 L mol -1 cm -1 , 5.26×10 -2 μg cm -2 , 0.022 and 0.072 μg mL -1 , respectively. The optimum reaction conditions and other analytical parameters were evaluated. The proposed method has been successfully applied for the determination of arsenic in various environmental and biological samples.
20 citations
Journal Article•
TL;DR: In this paper, the synthesis of new 3-acetylcinnolines has been carried out by the intramolecular cyclisation of phenylhydrazonoacetylacetone 1a-d. Compounds have been screened for their antifungal and antibacterial activity.
Abstract: Synthesis of some new 3-acetylcinnolines 2a-d has been carried out by the intramolecular cyclisation of phenylhydrazonoacetylacetone 1a-d. 3-Acetyl-4,8-dimethylcinnoline 2b has been converted to 3-(bromoacetyl)-4,8-dimethylcinnoline 3b. The 3-(bromoacetyl)-4,8-dimethylcinnoline 3b has then been treated with thioacetamide 4a, thiourea 4b and substituted thioureas 4c-f in ethanol to get 4-(4,8-dimethylcinnolin-3-yl)-2-methyl-l,3-thiazole 5a, 4-(4,8-dimethylcinnolin-3-yl)-2-amino-l,3-thiazole 5b and N- (aryl)-4-(4,8-dimethylcinnolin-3-yl)-l,3-thiazol-2-amines 5c-f. The newly synthesized compounds have been characterized by elemental analysis, 1R, 1 H NMR and mass spectral studies. Compounds have been screened for their antifungal and antibacterial activity. 4,7-dimethyl-3-acetylcinnoline 2c has emerged as a promising antibacterial agent and N-(3-chlorophenyl)-4-(4,8-dimethylcinnolin-3-yl)-1,3-thiazol-2-amine 5d has emerged as a promising antifungal agent.
15 citations
Journal Article•
TL;DR: In this article, a simple, rapid and sensitive spectrophotometric method has been developed for the determination of trace amounts of selenium in water samples, soil, plant materials and human hair.
Abstract: A simple, rapid and sensitive spectrophotometric method has been developed for the determination of trace amounts of selenium in water samples, soil, plant materials and human hair. The proposed method is based on the reaction of selenium with potassium iodide in acidic medium to liberate iodine. The liberated iodine bleaches the violet colour of azure B, which is measured at 644 nm. This decrease in absorbance is directly proportional to selenium concentration. Beer’s Law was obeyed in the range 2.0-10.0 μgmL of selenium. The molar absorptivity, Sandell’s sensitivity, quantitation limit and detection limit of the method were found to be 0.9473 × 10 5 L mol -1 cm , 8.33 × 10 μg cm, 0.070 μgmL and 0.023 μgmL, respectively. The proposed method has been successfully applied to the determination of selenium in various samples.
15 citations
TL;DR: The title compound, C17H15FO3, crystallizes in a centrosymmetric space group and thus does not show any non-linear optical activity and there are two molecules in the asymmetric unit.
Abstract: The title compound, C17H15FO3, crystallizes in a centrosymmetric space group and thus does not show any non-linear optical activity. There are two molecules in the asymmetric unit.
13 citations
12 citations
TL;DR: The planar molecules of the title compound, C15H13FO2, are normal as discussed by the authors, and the non-centrosymmetric crystal packing may be influenced by weak C−H⋯O and C−F inter-actions.
Abstract: The planar molecules of the title compound, C15H13FO2, are normal. The non-centrosymmetric crystal packing may be influenced by weak C—H⋯O and C—H⋯F interactions.
11 citations
TL;DR: In this paper, a smooth one-step synthesis of 2-(2-bromo-5methoxyphenyl)-5-(3-arylidene)-1,3-thiazolo[3, 2-b]-1,2,4-triazol-6-(5H)-ones (4a-n) is described.
Abstract: A smooth one-step synthesis of 2-(2-bromo-5-methoxyphenyl)-5-(3-arylidene)-1,3-thiazolo[3,2-b]-1,2,4-triazol-6-(5H)-ones (4a–n) is described. The newly prepared compounds are characterized by analytical and IR, 1 H NMR, 13 C NMR, and FABMS spectral analysis. A few compounds are screened for anticonvulsant activity. Compounds 4i and 4n exhibit promising anticonvulsant activity and are recommended for further studies.
Journal Article•
TL;DR: In this article, a highly sensitive and selective spectophotometric method has been developed for the determination of iodate (IO 3 ) in table salt and sea water, which is based on the oxidation of leuco xylene cyanol FF (LXCFF) to its blue form of xylene Cyanol FF by iodate in sulfuric acid medium, the absorbance of the dye is measured in an acetate buffer medium at 620 nm.
Abstract: A highly sensitive and selective spectophotometric method has been developed for the determination of iodate (IO 3 - ) in table salt and sea water. The proposed method is based on the oxidation of leuco xylene cyanol FF (LXCFF) to its blue form of xylene cyanol FF by iodate in sulfuric acid medium, the absorbance of the dye is measured in an acetate buffer medium (pH 4.0) at 620 nm. Beer's law is obeyed in the range 0.4-14 μg mL -1 of iodate. The molar absorptivity, Sandell's sensitivity, detection limit and quantitation limit of the method were found to be 1.71 × 10 4 Lmol -1 cm -1 , 1.02 x 10 -2 μg cm -2 , 0.026 μg mL -1 and 0.0806 μg mL -1 respectively. The optimum reaction conditions and other analytical conditions were evaluated. The effect of interfering ions on the determination is described. The proposed method has been successfully applied to the determination of the iodate in the table salt and sea water.
TL;DR: Almost all the compounds are found to possess promising antibacterial and antifungal activity against all tested microorganisms.
Abstract: Some new 4-{2-[(aryl) amino]-1,3-thiazol-4-yl}benzene-1,2-diols are prepared and characterized by spectral analysis. The newly prepared compounds are studied for their antibacterial and antifungal activity. Interestingly, almost all the compounds are found to possess promising antibacterial and antifungal activity against all tested microorganisms.
TL;DR: Shan et al. as discussed by the authors confirmed that C19H18O3 has ortho-rhombic symmetry and the only possible inter-molecular interaction is a weak C-H⋯O bond.
Abstract: The title compound, C19H18O3, is confirmed to crystallize with orthorhombic symmetry [Shan et al. (1999). Z. Kristallogr. New Cryst. Struct. 214, 381–382; Marsh (2004). Acta Cryst. B60, 252–253]. The molecule has crystallographically imposed twofold symmetry and the only possible intermolecular interaction is a weak C—H⋯O bond.
Journal Article•
TL;DR: In this paper, the authors used spectral analysis and screened for antibacterial and antifungal activity and anti-inflammatory activity for the synthesis of a number of compounds, including 3-amino-2-methyl-5,6,7,8-tetrahydro[1]benzothieno[2,3-d]pyrimid-4(3H)-one 3a and 3-amide-2.
Abstract: Ethyl 2-amino-4,5,6,7-tetrahydro-1-benzothiophene-3-carboxylate 1 has been converted into ethyl 2-(acetylamino)-4,5,6,7-tetrahydro-1-benzothiophene-3-carboxylate 2a and ethyl 2-(propionylamino)-4,5,6,7-tetrahydro-1-benzothiophene-3-carboxylate 2b. Compounds 2a and 2b on treatment with hydrazine hydrate give 3-amino-2-methyl-5,6,7,8-tetrahydro[1]benzothieno[2,3-d]pyrimid-4(3H)-one 3a and 3-amino-2-ethyl-5,6,7,8-tetrahydro[1]benzothieno[2,3-d]pyrimid-4(3H)-one 3b respectively. Compounds 3a and 3b have been treated with aromatic aldehydes to get Schiff bases 4a-1 and 5a-1. The compounds have been characterized by spectral analysis and screened for antibacterial and antifungal activity. Eight compounds have also been screened for their antiinflammatory activity. A few of the compounds exhibit promising biological activity.
TL;DR: The geometrical parameters for the title compound, C16H12BrClO2, are normal as mentioned in this paper, and the observed bond lengths and angles imply that there is little electronic conjugation between the two benzene ring systems.
Abstract: The geometrical parameters for the title compound, C16H12BrClO2, are normal. The observed bond lengths and angles imply that there is little electronic conjugation between the two benzene ring systems. An intramolecular C—H⋯Br interaction may help to establish the molecular conformation. The crystal packing results in a centrosymmetric structure.
TL;DR: The title compound, C17H12Cl2O, shows significant non-linear optical activity as discussed by the authors, and a twofold rotation axis passes through the carbonyl group. But it cannot be used for optical imaging.
Abstract: The title compound, C17H12Cl2O, shows significant non-linear optical activity. A twofold rotation axis passes through the carbonyl group.
TL;DR: In this article, a simple, rapid and sensitive spectrophotometric method has been developed for the determination of iodate (IO3-) in table salt and sea water, which is based on the reaction of iodates with potassium iodide in an acid medium to liberate iodine.
Abstract: A simple, rapid and sensitive spectrophotometric method has been developed for the determination of iodate (IO3-) in table salt and sea water. The proposed method is based on the reaction of iodate with potassium iodide in an acid medium to liberate iodine. The liberated iodine bleaches the blue color of methylene blue and is measured at 665.6 nm. This decrease in absorbance is directly proportional to the iodate concentration and obeys Beer’s law in the range of 0.5-14 μgmL–1 of IO3-. The molar absorptivity, Sandell’s sensitivity, detection limit and quantitation limit of the method were found to be 1.24 x 104 Lmol-1cm–1, 1.41 x 10-2 μgcm-2, 0.048 μgmL–1 and 0.145 μgmL-1, respectively. The optimum reaction conditions and other analytical conditions were evaluated. The effect of interfering ions on the determination has been described. The proposed method has been successfully applied to the determination of the iodate in the table salt and sea water.
Journal Article•
TL;DR: In this article, a method obeys Beer's law in the concentration range of 0.5-20 μg mL −1 of selenium with phenylhydrazinep-sulphonic acid-acetylacetone and 1-24 μg mL−1 of SEH with P-SULPHONIC acid-ethylacetoacetate couples.
Abstract: respectively. The method obeys Beer’s law in the concentration range of 0.5-20 μg mL −1 of selenium with phenylhydrazinep-sulphonic acid-acetylacetone and 1-24 μg mL −1 of selenium with phenylhydrazine-p-sulphonic acid-ethylacetoacetate couples. The molar absorptivity, Sandell’s sensitivity of the systems with phenylhydrazine-p-sulphonic acid-acetylacetone and phenylhydrazine-p-sulphonic acid-ethylacetoacetate couples were found to be 1.02×10 4 Lmol −1 cm −1 , 7.69×10 −3 μg cm −2 and 1.18×10 4 L mol −1 cm −1 , 6.67×10 −3 μg cm −2 , respectively. The developed method has been successfully applied for the
TL;DR: The geometrical parameters for the title compound, C13H17NO3S, are normal as mentioned in this paper, and the planar mol-ecular conformation is reinforced by an intra-molecular N-H⋯O inter-action.
Abstract: The geometrical parameters for the title compound, C13H17NO3S, are normal. The planar molecular conformation is reinforced by an intramolecular N—H⋯O interaction.
TL;DR: The geometrical parameters for the title compound, C16H13ClO2, are normal as discussed by the authors, and packing in a non-centrosymmetric space group, which is consistent with the non-zero second harmonic generation response, may be influenced by a C-H⋯O inter-action.
Abstract: The geometrical parameters for the title compound, C16H13ClO2, are normal. Packing in a non-centrosymmetric space group, which is consistent with the non-zero second harmonic generation response, may be influenced by a C—H⋯O interaction.
TL;DR: In this paper, the central C=C double bond is trans configured and the molecule consists of two essentially planar parts which are twisted by 26.89 (5) degrees with respect to each other.
Abstract: In the title biologically active compound, C16H12O3, the central C=C double bond is trans configured. The molecule consists of two essentially planar parts which are twisted by 26.89 (5)degrees with respect to each other.
TL;DR: In the title molecule, C14H9BrO3S, the the prop-2-en-1-one (enone) fragment is close to planar and it subtends dihedral angles of 5.3 (4)° with respect to the thiophene and benzene rings, respectively.
Abstract: In the title molecule, C14H9BrO3S, the the prop-2-en-1-one (enone) fragment is close to planar [C—C—C—O = 2.5 (7)°] and it subtends dihedral angles of 12.5 (3) and 5.3 (4)° with respect to the thiophene and benzene rings, respectively. The dihedral angle between the aromatic ring systems is 12.60 (18)°. Two C—H⋯O interactions help to consolidate the non-centrosymmetic crystal packing, which features undulating (100) sheets incorporating C(11) and C(12) chain motifs.
TL;DR: The geometric parameters for the essentially planar molcule of the title compound, C9H8FN3O, are normal as discussed by the authors, and a network of N−H⋯O and N−N−N hydrogen bonds helps to establish the crystal packing.
Abstract: The geometric parameters for the essentially planar molecule of the title compound, C9H8FN3O, are normal. A network of N—H⋯O and N—H⋯N hydrogen bonds helps to establish the crystal packing.
TL;DR: The title compound, C24H18O2, is a chalcone derivative as discussed by the authors, and the torsion angle between the mean planes of the two naphthalene groups is 54.41 (2)degrees.
Abstract: The title compound, C24H18O2, is a chalcone derivative The torsion angle between the mean planes of the two naphthalene groups is 54.41 (2)degrees.
TL;DR: New 4/5//6//7/7-nitro-N′-(4-aryl-1,3-thiazol-2-yl)-1H-indole-2 carbohydrazides (4a-t) were prepared by treating respective nitroindole thiosemicarbazide with aromatic acylbromides as mentioned in this paper.
Abstract: New 4-/5-/6-/7-nitro-N′-(4-aryl-1,3-thiazol-2-yl)-1H-indole-2-carbohydrazides (4a–t) were prepared by treating respective nitroindole thiosemicarbazide with aromatic acylbromides. The newly synthesized compounds were characterized by analytical and spectral data. The compounds were also screened for antifungal and antibacterial activity. Some of the compounds exhibited promising antimicrobial activity.
TL;DR: The C14H11BrO2S compound as discussed by the authors exhibits distorted geometrical values that may be attributed to an H⋯Br close contact in the crystal structure.
Abstract: The molecules of the title compound, C14H11BrO2S, display some distorted geometrical values that may be ascribed to an H⋯Br close contact. In the crystal structure, the molecules form translation-symmetry-generated infinite chains by way of a C—H⋯O interaction.
TL;DR: C22H22O3 as mentioned in this paper is a cyclohexanone derivative with a two-photon absorption and its metrical parameters are similar to those of related C-H-21O3 derivatives.
Abstract: The title compound, C22H22O3, demonstrates a two-photon absorption Its metrical parameters are similar to those of related cyclohexanone derivatives In the crystal structure, two sets of centrosymmetric dimers formed by weak C-H center dot center dot center dot O intermolecular hydrogen bonds combine to form molecular tapes along 101]
TL;DR: The title compound, C9H11N3S2, crystallizes with two molecules in the asymmetric unit, which differ mainly in the degree of planarity as mentioned in this paper, and the C=N double bonds are trans configured.
Abstract: The title compound, C9H11N3S2, crystallizes with two molecules in the asymmetric unit, which differ mainly in the degree of planarity. The C=N double bonds are trans configured. Geometric parameters are in the usual ranges. The crystal structure is characterized by N-H center dot center dot center dot N and N-H center dot center dot center dot S hydrogen bonds.