The 13C and 15N absolute shieldings of 28 compounds have been calculated at the GIAO/B3LYP/6-311 + + G** level to complete a collection of data already published. This has allowed us to devise new equations relating δ and σ for these nuclei based on 461 points (13C) and 70(72) points (15N). Copyright © 2007 John Wiley & Sons, Ltd.

Statistical analysis of 13C and 15N NMR chemical shifts from GIAO/B3LYP/6‐311 + + G** calculated absolute shieldings

Metal complexes of (Z)-2-(pyrrolidin-2-ylidene)hydrazinecarbothioamide (L) with Cu(II), Co(II), and Ni(II) chlorides were tested against selected types of fungi and were found to have significant antifungal activities The free-radical-scavenging ability of the metal complexes was determined by their interaction with the stable free radical 2,2′′-diphenyl-1-picrylhydrazyl, and all the compounds showed encouraging antioxidant activities DFT calculations of the Cu complex were performed using molecular structures with optimized geometries Molecular orbital calculations provide a detailed description of the orbitals, including spatial characteristics, nodal patterns, and the contributions of individual atoms

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Antifungal and antioxidant activities of pyrrolidone thiosemicarbazone complexes.

Reactive oxygen species, along with reactive nitrogen species, may play an important role in the pathogenesis and progress of many diseases, including cancer, diabetes and sickle cell disease. It has been postulated that hydroxyurea, one of the main treatments in sickle cell disease, achieves its activity partly also through its antioxidant properties. A series of hydroxyurea derivatives of L- and D-amino acid amides and cycloalkyl-N-aryl-hydroxamic acids was synthesized and investigated for their radical scavenging activity, chelating properties and antioxidant activity. All the compounds showed exceptional antiradical activities. For example, free radical scavenging activities of investigated hydroxyureas were higher than the activity of standard antioxidant, butylated hydroxyanisole (BHA). Moreover, most of the investigated hydroxamic acids were stronger Fe2+ ion chelators than quercetin. In addition, the investigated compounds, especially hydroxamic acids, were proven to be excellent antioxidants. They were as effective as BHA in inhibiting b-carotene-linoleic acid coupled oxidation. It is reasonable to assume that the antioxidant activity of the investigated compounds could contribute to their previously proven biological properties as cytostatic and antiviral agents.

Antiradical, chelating and antioxidant activities of hydroxamic acids and hydroxyureas

One-pot microwave assisted synthesis under green chemistry conditions, antioxidant screening, and cytotoxicity assessments of benzimidazole Schiff bases and pyrimido[1,2-a]benzimidazol-3(4H)-ones.

Single crystal XRD, DFT investigations and molecular docking study of 2- ((1,5-dimethyl-3-oxo-2-phenyl-2,3-dihydro-1H-pyrazol-4-yl)amino)naphthalene-1,4-dione as a potential anti- cancer lead molecule.

Department of Chemistry, Kafkas University, 36100 Kars, Turkey. *Author to whom correspondence should be addressed; e-mail: hyuksek98@yahoo.com Received: 7 April 2005 / Accepted: 21 August 2005 / Published: 25 August 2005 Abstract: 3-Alkyl(aryl)-4-amino-4,5-dihydro-1H-1,2,4-triazol-5-ones (1) reacted with 5-methylfuran-2-carboxyaldehyde to afford the corresponding 3-alkyl(aryl)-4-(5-methyl-2-furylmethylenamino)-4,5-dihydro-1H-1,2,4-triazol-5-ones (2). Four newly synthesized compounds have been characterized by elemental analyses, IR,

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Synthesis and GIAO NMR Calculations for Some Novel 4-Heteroarylidenamino-4,5-dihydro-1H-1,2,4-triazol-5-one Derivatives: Comparison of Theoretical and Experimental 1Hand 13C- Chemical Shifts

3-Alkyl(aryl)-4-amino-4,5-dihydro-1H-1,2,4-triazol-5-ones 2a-g reacted with4-diethylaminobenzaldehyde to afford the corresponding 3-alkyl(aryl)-4-(4-diethylaminobenzylidenamino)-4,5-dihydro-1H-1,2,4-triazol-5-ones 3a-g. The acetylationreactions of compounds 3a-e were investigated and compounds 4a-e were thus obtained.The new compounds were characterized using IR, 1H-NMR, 13C-NMR, UV and MSspectral data. In addition, the newly synthesized compounds 3a-g were titratedpotentiometrically with tetrabutylammonium hydroxide in four non-aqueous solvents suchas isopropyl alcohol, tert-butyl alcohol, acetone and N,N-dimethylformamide (DMF), andthe half-neutralization potential values and the corresponding pKa values were determinedfor all cases. Moreover, 3 and 4 type compounds were also screened for their antioxidantactivities.

https://www.mdpi.com/1420-3049/13/1/107/pdf

Synthesis, Acidity and Antioxidant Properties of Some Novel 3,4-disubstituted-4,5-dihydro-1H-1,2,4-triazol-5-one Derivatives

The synthesis of 3-alkyl(aryl)-4-[4-(dimethylamino)benzylideneamino]-4,5-dihydro-1 H -1,2,4-triazol-5-ones ( 3 ) from the reactions of 3-alkyl(aryl)-4-amino-4,5-dihydro-1 H -1,2,4-triazol-5-ones ( 2 ) with 4-(dimethylamino)benzaldehyde is described. The newly synthesized 3 type compounds were titrated potentiometrically with tetrabutylammonium hydroxide in three non-aqueous solvents, including acetonitrile, isopropyl alcohol and N , N -dimethylformamide. The half-neutralization potential values and the corresponding p K a values were determined for all cases. Thus, the effects of solvents and molecular structure upon acidity were investigated. In addition, N -acetyl derivatives of 3 type compounds were also obtained. The new synthesized compounds in the study were fully characterized.

Synthesis and Potentiometric Titrations of Some New 4-(Benzylideneamino)-4,5-dihydro-1H-1,2,4-triazol-5-one Derivatives in Non-Aqueous Media

3-Alkyl(Aryl)-4-amino-4,5-dihydro-1H-1,2,4-triazol-5-ones (2) reacted with 2-furoyl chloride and thiophene-2-carbonyl chloride to afford the corresponding 3- alkyl(aryl)-4-(2-furoylamino)-4,5-dihydro-1H-1,2,4-triazol-5-ones (3) and 3-alkyl(aryl)- 4-(2-thienylcarbonylamino)-4,5-dihydro-1H-1,2,4-triazol-5-ones (4), respectively. The new compounds synthesized were characterized by using IR, 1H-NMR, 13C-NMR and UV spectral data together with elemental analysis. In addition, to investigate the effects of solvents and molecular structure upon acidity, compounds 3 and 4 were titrated potentiometrically with tetrabutylammonium hydroxide in four non-aqueous solvents (isopropyl alcohol, tert-butyl alcohol, N,N-dimethylformamide and acetonitrile). The half-neutralization potential values and the corresponding pKa values were determined for all cases.

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Muzaffer Alkan

Papers

Synthesis and GIAO NMR Calculations for Some Novel 4-Heteroarylidenamino-4,5-dihydro-1H-1,2,4-triazol-5-one Derivatives: Comparison of Theoretical and Experimental 1Hand 13C- Chemical Shifts

Synthesis, Acidity and Antioxidant Properties of Some Novel 3,4-disubstituted-4,5-dihydro-1H-1,2,4-triazol-5-one Derivatives

Synthesis and Potentiometric Titrations of Some New 4-(Benzylideneamino)-4,5-dihydro-1H-1,2,4-triazol-5-one Derivatives in Non-Aqueous Media

Synthesis and Determination of pKa Values of Some New 3,4-Disubstituted-4,5-Dihydro-1H-1,2,4-triazol-5-one Derivatives in Non-aqueous Solvents

Synthesis, determination of pKa values and GIAO NMR calculations of some new 3-alkyl-4-(p-methoxybenzoylamino)-4,5-dihydro-1H-1,2,4-triazol-5-ones