Investigation of the interaction between S-isoalkyl derivatives of the thiosalicylic acid and human serum albumin.

S-isoalkyl derivatives of thiosalicylic acid (isopropyl-(L1), isobutyl-(L2) and isoamyl-(L3)) were selected in order to investigate the binding interaction with the human serum albumin (HSA) using different spectroscopic methods and molecular docking simulation. Association constants and number of binding sites were used to analyze the quenching mechanism. The experimental results showed that the fluorescence quenching of HSA by L1, L2 and L3 occurs because of static quenching and that binding processes were spontaneous, with the leading forces in bonding by hydrogen bonding, hydrophobic interactions, and electrostatic interactions.

Exploring heterometallic bridged Pt(II)-Zn(II) complexes as potential antitumor agents.

The four novel complexes [{cis-PtCl(NH)(μ-4,4'-bipyridyl)ZnCl(terpy)}](ClO) (C1), [{trans-PtCl(NH)(μ-4,4'-bipyridyl)ZnCl(terpy)}](ClO) (C2), [{cis-PtCl(NH)(μ-pyrazine)ZnCl(terpy)}](ClO) (C3) and [{trans-PtCl(NH)(μ-pyrazine)ZnCl(terpy)}](ClO) (C4) (where terpy = 2,2':6',2''-terpyridine) were synthesized and characterized. Acid-base titrations and concentration dependent kinetic measurements for the reactions with biologically relevant ligands such as guanosine-5'-monophosphate (5'-GMP), inosine-5'-monophosphate (5'-IMP) and glutathione (GSH), were studied at pH 7.4 and 37 °C.

Effect of Caffeine and Flavonoids on the Binding of Tigecycline to Human Serum Albumin: A Spectroscopic Study and Molecular Docking.

Human serum albumin (HSA) has a very significant role in the transport of drugs, in their pharmacokinetic and pharmacodynamic properties, as well as the unbound concentration of drugs in circulating plasma. The aim of this study was to look into the competition between tigecycline (TGC) and alkaloid (ALK) (caffeine (CAF)), and flavonoids (FLAVs) (catechin (CAT), quercetin (QUE), and diosmin (DIO)) in binding to HSA in simulated physiological conditions using multiple spectroscopic measurements and docking simulations. Fluorescence analysis was used to find the binding and quenching properties of double HSA-TGC and triple HSA-TGC-CAF/FLAV systems.

Interaction between olanzapine and human serum albumin and effect of metal ions, caffeine and flavonoids on the binding: A spectroscopic study.

In this study, the binding of olanzapine (OLZ) to human serum albumin (HSA) and the influence of metal ions (Ca, Mg, Cu, Zn, Fe), caffeine (CAF) and flavonoids (diosmin (DIO), catechin (CAT), quercetin (QUE)), on their affinity, was investigated by fluorescence spectroscopy and UV-vis absorption spectroscopy. Fluorescence experiments suggest that OLZ quench the fluorescence of HSA through the mixed quenching mechanism and non-radiation energy transferring as a result of the HSA-OLZ complex formation. OLZ spontaneously bind in the site I on HSA, and according to thermodynamic parameters, the reaction was spontaneous and mainly driven by hydrogen bonds and van der Waals interactions.

Homo- and hetero-dinuclear Pt(II)/Pd(II) complexes: studies of hydrolysis, nucleophilic substitution reactions, DNA/BSA interactions, DFT calculations, molecular docking and cytotoxic activity.

Three dinuclear complexes [Pd2(tpbd)Cl2]Cl2 (PP1), [Pt2(tpbd)Cl2]Cl2 (PP2) and [PdPt(tpbd)Cl2]Cl2 (PP3) (tpbd = N,N,N',N'-tetrakis(2-pyridylmethyl)benzene-1,4-diamine) have been synthesized and characterized and the protonation constants of their corresponding diaqua analogues have been determined. Also, in water solution, the aqua analogues of these complexes exist as mono-hydroxo, di-hydroxo and dimer μ-hydroxo complexes in the pH between 3.0 and 11.

Synthesis, characterization, HSA/DNA interactions and antitumor activity of new [Ru(η-p-cymene)Cl(L)] complexes.

Three new ruthenium(II) complexes were synthesized from different substituted isothiazole ligands 5-(methylamino)-3-pyrrolidine-1-ylisothiazole-4-carbonitrile (1), 5-(methylamino)-3-(4-methylpiperazine-1-yl)isothiazole-4-carbonitrile (2) and 5-(methylamino)-3-morpholine-4-ylisothiazole-4-carbonitrile (3): [Ru(η-p-cymene)Cl(L1)]·HO (4), [Ru(η-p-cymene)Cl(L2)] (5) and [Ru(η-p-cymene)Cl(L3)] (6). All complexes were characterized by IR, UV-Vis, NMR spectroscopy, and elemental analysis. The molecular structures of all ligands and complexes 4 and 6 were determined by an X-ray.

Synthesis and characterisation of bismacrocyclic DO3A-amide derivatives - an approach towards metal-responsive PARACEST agents.

Three new bismacrocyclic Ln(3+) chelates consisting of triamide derivatives of cyclen with glycine, methyl and tert-butyl substituents (, respectively) linked to an acyclic EGTA-derived calcium chelator were synthesised as potential MRI contrast agents (EGTA - ethylene glycol-bis(2-aminoethylether)-N,N,N',N'-tetraacetic acid). Eu(3+) and Yb(3+) complexes of were investigated as chemical exchange saturation transfer (CEST) agents. Moderate to minor CEST effects were observed for , and complexes in the absence of Ca(2+), with negligible changes upon addition of this metal ion.

Synthesis of novel palladium(II) complexes with oxalic acid diamide derivatives and their interaction with nucleosides and proteins. Structural, solution, and computational study.

Novel palladium complexes, KH[Pd(obap)]2·3H2O (3) with oxamido-N-aminopropyl-N'-benzoic acid and [Pd(apox)] (4) with N,N'-bis(3-aminopropyl)ethanediamide, were synthesized. Exhaustive synthetic, solution and structural studies of the two Pd(ii) complexes are reported. The binary and ternary systems of the Pd(ii) ion with H2apox or H3obap as primary ligands and nucleosides (Ado or Cyt) as secondary ligands, are investigated in order to better understand their equilibrium chemistry.

Antitumor effects of a tetradentate amido-carboxylate ligands and corresponding square-planar palladium(II) complexes toward some cancer cells. Crystal structure, DFT modeling and ligand to DNA probe docking simulation.

Novel square-planar palladium(II) complexes with O-N-N-O-type ligands H4mda (H4mda=malamido-N,N'-diacetic acid) and H4obp (H4obp=oxamido-N,N'-di-3-propionic acid) were prepared and characterized. The ligands coordinate to the palladium(II) ion via two pairs of deprotonated ligating atoms with square chelation. A four coordinate, square-planar geometry was verified crystallographicaly for the K2[Pd(mda)]·H2O complex.

Antiproliferative activity and QSAR studies of a series of new 4-aminomethylidene derivatives of some pyrazol-5-ones.

Twenty five 4-aminomethylidene derivatives obtained from 3-phenyl-2-pyrazolin-5-one and 1,3-diphenyl-2-pyrazolin-5-one were synthesized and tested for their antiproliferative activity against human breast cancer MDA-MB-361 and MDA-MB-453 cell lines. The compounds derived from 1,3-diphenyl-2-pyrazolin-5-one exhibited the most remarkable activity in the treatment of both cell lines. In vitro antiproliferative activities were accompanied by an important apoptotic fraction of both cell lines; also, compounds inhibited key endothelial cell functions implicated in invasion and angiogenesis.

Equilibrium studies of the reactions of palladium(II) bis(imidazolin-2-imine) complexes with biologically relevant nucleophiles. The crystal structures of [(TLtBu)PdCl]ClO4 and [(BLiPr)PdCl2].

The kinetics and the mechanism of the substitution reactions of the complex [(TL(tBu))PdCl](+), where TL(tBu) is 2,6-bis[(1,3-di-tert-butylimidazolin-2-imino)methyl]pyridine, with nucleophiles (guanosine-5'-monophosphate (5'-GMP), l-Methionine (l-Met) and l-Histidine (l-His)) were studied using variable-temperature stopped-flow techniques in aqueous 0.1 M NaClO(4) with 10 mM NaCl at 298 K. The order of reactivity is: l-Met > 5'-GMP > l-His.

Complexes of hydroxy(thio)pyrone and hydroxy(thio)pyridinone with Zn(II) and Mo(VI). Thermodynamic stability and insulin-mimetic activity.

The development of metal-containing pharmaceuticals as insulin-mimetics has been the object of recent worldwide research. We have examined a series of zinc(II) and molybdenum(VI) complexes with model O,S-donor ligands (thiomaltol and 1,2-dimethyl-3-hydroxypyridine-4-thione (DMHTP)) and the corresponding O,O-analogues (maltol and DMHP) for their insulin-mimetic activity. Aimed at getting structure-activity relationships, some physical-chemical properties were also studied, such as metal-complex formation, speciation at different pH conditions and ligand lipophilicity.

Study of Solution Equilibria Between Gadolinium(III) Ion and Moxifloxacin.

The complex formation equilibria between gadolinium(III) ion and moxifloxacin (MOXI) were studied in aqueous solutions. The investigations were performed by glass electrode potentiometric (ionic medium: 0.1mol dm-3 LiCl, 298 K) and UV spectrophotometric measurements.

Solution Equilibria between Aluminum(III) Ion and L-histidine or L-tyrosine.

Toxic effects due to high aluminum body loads were observed in a number of conditions following ingestion of Al-containing antacids. Bio-availability of aluminum depends not only on the solubility of the ingested salt but also on the physico-chemical properties of the soluble Al complexes formed in body fluids. Amino acids may, upon interaction with Al-salts, form absorbable Al-complexes.

Biologically relevant O,S-donor compounds. Synthesis, molybdenum complexation and xanthine oxidase inhibition.

Two O,S-donor ligands, hydroxythiopyrone and hydroxythiopyridinone derivatives, were developed and studied, as well as the corresponding O,O-derivatives, with a view to their potential pharmacological applications as xanthine oxidase (XO) inhibitors. The biological assays revealed that the O,S-ligands present high inhibitory activity towards XO (nanomolar order, close to that of the pharmaceutical drug allopurinol), in contrast to the corresponding O,O-analogues. Due to the biomedical relevance of this molybdenum-containing enzyme, the corresponding Mo(VI) complexes were studied both in solution and in the solid state, aimed at identifying the source of the biological properties.

Solution equilibria between aluminum(III) ion and some fluoroquinolone family members. Spectroscopic and potentiometric study.

Complex formation between aluminum(III) ion and fluoroquinolone antibacterials-either moxifloxacin (4th generation antibiotic) or fleroxacin (2nd generation antibiotic) were studied in aqueous solutions without and in the presence of sodium dodecylsulfate (SDS). The investigations were performed by glass electrode potentiometric (ionic medium: 0.1 mol/dm(3) LiCl, 298 K), UV spectrophotometric, multinuclear (1H and 13C) magnetic resonance and ESI-MS measurements.

Equilibrium, kinetic and HPLC study of the reactions between platinum(II) complexes and DNA constituents in the presence and absence of glutathione.

The complex formation equilibria of [Pt(SMC)(H(2)O)(2)](+) and [Pt(terpy)H(2)O](2+), where SMC =S-methyl-L-cysteine and terpy = 2,2':6',2"-terpyridine, with some biologically relevant ligands such as inosine (INO), inosine-5'-monophosphate (5'-IMP), guanosine-5'-monophosphate (5'-GMP) and glutathione (GSH) were studied. The stoichiometry and stability constants of the complexes formed are reported, and the concentration distribution of the various complex species have been evaluated as a function of pH. Also the kinetics and mechanism of the complex formation reactions were studied as a function of nucleophile concentration and temperature.

[Some interesting cases of pulmonary echinococcosis].

The authors had the opportunity in the interim of the past fifteen years to treat at the hospital in Zadar 277 patients suffering from hydatid disease of different body organs. The most frequently affected was the liver--56.3%, followed by the lungs--24.

[Manifestation of echinococcosis in the chest cavity].

In the interim from 1970 to 1974, the authors had occasion to encounter several patients with symptoms of hydatid disease in the chest, particularly with pleural effusion not always easily differentiated from effusions other etiology. This pertains especially to hydatid disease of the liver with a perforation through the diaphragm and clinic and roentgen findings revealing only thoracic signs. All the clinical diagnosis in cases of patients who had undergone an operation, were confirmed by patho-anatomic findings.