Stability and Structural Studies on Ni(II)–5-Fluorouracil Mixed Ligand Complex Systems

Shobana, Sutha; Subramaniam, P.; Dharmaraja, Jeyaprakash; Arvindnarayan, Sundaram

doi:10.1007/s10953-016-0440-7

Cited by 4 publications

(3 citation statements)

References 38 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The obtained value is more positive than those given for other heteroligand systems [9,40], most likely due to the presence of a phenol ring affecting the stability of the heteroligand complex. It appears that the stacking interaction occurring between the AlaSal aromatic ring, which is flexible, and the PicHA pyridine ring, which is rigidly attached to the metal ion in an equatorial position, results in the heteroligand complex demonstrating greater stability than the binary complex [CoL'H] + with one protonated molecule [41].…”

Section: Heteroligand Complex Formation Equilibriacontrasting

confidence: 58%

See 1 more Smart Citation

Chemical Characterization and Biological Evaluation of New Cobalt(II) Complexes with Bioactive Ligands, 2-Picolinehydroxamic Acid and Reduced Schiff Base N-(2-Hydroxybenzyl)alanine, in Terms of DNA Binding and Antimicrobial Activity

et al. 2021

View full text Add to dashboard Cite

Five new heteroligand cobalt(II) complexes with 2-picolinehydroxamic acid and reduced Schiff base, N-(2-hydroxybenzyl)alanine, were formed in an aqueous solution over a wide pH range. The coordination properties of ligands towards the metal ion were determined using a pH-metric method, and then the speciation model was confirmed by UV–Vis studies. A stacking interaction between the Schiff base phenol ring and the 2-picolinehydroxamic acid pyridine ring was found to improve the stability of the heteroligand species, indicating more effective coordination in mixed-ligand complexes than in their respective binary systems. The antimicrobial properties of heteroligand complexes were determined against Gram-negative and Gram-positive bacteria, as well as fungal strains. The formulation demonstrated the highest bacteriostatic and bactericidal activity (3.65 mM) against two strains of Gram-negative Helicobacter pylori bacteria and towards Candida albicans and Candida glabrata; this is important due to the potential co-existence of these microorganisms in the gastric milieu and their role in the development of gastritis. The binary complexes in the cobalt(II)—2-picolinehydroxamic acid system and 2-picolinehydroxamic acid were not cytotoxic against L929 mouse fibroblasts, neither freshly prepared solutions or after two weeks’ storage. By comparison, the heteroligand complexes within the range 0.91–3.65 mM diminished the metabolic activity of L929 cells, which was correlated with increased damage to cell nuclei. The concentration of the heteroligand species increased over time; therefore, the complexes stored for two weeks exhibited stronger anticellular toxicity than the freshly prepared samples. The complexes formed in an aqueous solution under physiological pH effectively bound to calf thymus DNA in an intercalative manner. This DNA-binding ability may underpin the antimicrobial/antifungal activity of the heteroligand complexes and their ability to downregulate the growth of eukaryotic cells.

show abstract

Section: Heteroligand Complex Formation Equilibriacontrasting

confidence: 58%

“…The disproportionation constant log 10 X [40], like ∆ log 10 β, also defines the stability of the heteroligand complexes relative to the binary complexes with two ligand molecules:…”

Section: Heteroligand Complex Formation Equilibriamentioning

confidence: 99%

Chemical Characterization and Biological Evaluation of New Cobalt(II) Complexes with Bioactive Ligands, 2-Picolinehydroxamic Acid and Reduced Schiff Base N-(2-Hydroxybenzyl)alanine, in Terms of DNA Binding and Antimicrobial Activity

et al. 2021

View full text Add to dashboard Cite

show abstract

“…Moreover, transition metals have been intensively studied in bioorganometallic chemistry to develop new metal based drugs [20,21]. Many studies have been reported in the literature about the determination of stability constants of transition metal complexes with various organic ligands with potential pharmacological activity [22][23][24][25][26]. The ability of complex formation between organic ligands and transition metals depends on a number of factors, such as the type of solvent, pH value of the solution and temperature [19,27].…”

Section: Introductionmentioning

confidence: 99%

Acid Dissociation Constants of 5,5-Diphenylpyrrolidine N-Aroylthioureas and Stability Constants of their Pt(II) and Ni(II) Complexes in Acetonitrile-Water Hydroorganic Solvent

Ersen¹,

Gemili²,

Sarı³

et al. 2017

Celal Bayar Üniversitesi Fen Bilimleri Dergisi

View full text Add to dashboard Cite

In this study, acid dissociation constants of 5,5-diphenylpyrrolidine N-aroylthiourea derivatives, exhibiting anti(myco)bacterial activity, were determined by potentiometric titration in 30% (v/v) acetonitrile-water hydroorganic solventat 25 ± 0.1 °C, at an ionic background of 0.1 mol / L of NaCl using the HYPERQUAD computer program. Three acid dissociation constants were determined for each compound 1a-e and we suggest that these acid dissociation constants are related to the carboxyl, enol and enthiol groups. Stability constants of their Pt(II) and Ni(II) complexes were also determined by potentiometric titration under the same conditions stated above using the HYPERQUAD computer program. The ligands behave as bidentate and bind to the metal atom via the S and O atoms. In various pH conditions, the different complex forms were formulated as ML2, MHL2, MH2L2, MH3L2, MH4L2, MH5L2 and MH-4L2 between Pt 2+ /Ni 2+ ions and 5,5-diphenylpyrrolidine N-aroylthioureas. Stability constants of the complexes show that the ligands 1a-e form complexes with Pt(II) and Ni(II) metals as 2:1. The stability of the complexes formed by the ligands and platinum were found to follow the order: 3d > 3a > 3e > 3c > 3b. The stability of the complexes formed by the ligands and nickel were found to follow the order: 4d > 4c > 4a > 4b > 4e. As a result, generally the platinum complexes formed with these ligands are more stable than their nickel complexes.

show abstract

Physico–chemical and extraction properties on alkali–treated Acacia pennata fiber

Sheeba,

Alagarasan,

Dharmaraja

et al. 2023

Environmental Research

View full text Add to dashboard Cite

Stability and Structural Studies on Ni(II)–5-Fluorouracil Mixed Ligand Complex Systems

Cited by 4 publications

References 38 publications

Chemical Characterization and Biological Evaluation of New Cobalt(II) Complexes with Bioactive Ligands, 2-Picolinehydroxamic Acid and Reduced Schiff Base N-(2-Hydroxybenzyl)alanine, in Terms of DNA Binding and Antimicrobial Activity

Chemical Characterization and Biological Evaluation of New Cobalt(II) Complexes with Bioactive Ligands, 2-Picolinehydroxamic Acid and Reduced Schiff Base N-(2-Hydroxybenzyl)alanine, in Terms of DNA Binding and Antimicrobial Activity

Acid Dissociation Constants of 5,5-Diphenylpyrrolidine N-Aroylthioureas and Stability Constants of their Pt(II) and Ni(II) Complexes in Acetonitrile-Water Hydroorganic Solvent

Physico–chemical and extraction properties on alkali–treated Acacia pennata fiber

Contact Info

Product

Resources

About