Interaction of VO-hydrazonates with lysozyme.

Vanadium compounds (VCs) exhibit a broad range of pharmacological properties, with their most significant medical applications being in the treatment of cancer and diabetes. The therapeutic effects and mode of action of VCs may be associated with their ability to bind proteins and, consequently, understanding the VC-protein interaction is of paramount importance. Among the promising VCs, the VO complex with the aroylhydrazone furan-2-carboxylic acid ((3-ethoxy-2-hydroxybenzylidene)hydrazide, hereafter denoted as VC1), deserves attention, since it exhibits cytotoxicity against various cancer cell lines, including HeLa.

Insights into the Theranostic Activity of Nonoxido V: Lysosome-Targeted Anticancer Metallodrugs.

Developing new anticancer agents can be useful, with the ability to diagnose and treat cancer worldwide. Previously, we focused on examining the effects of nonoxidovanadium(IV) complexes on insulin mimetic and cytotoxicity activity. In this study, in addition to the cytotoxic activity, we evaluated their bioimaging properties.

Ni-Unsymmetrical Salen Complex-Catalyzed One-Pot Multicomponent Reactions for Efficient Synthesis of Biologically Active 2-Amino-3-cyano-4-pyrans.

In this report, four new Ni(II)-unsymmetrical salen complexes, [NiL], were prepared by refluxing Ni(Ac)·4HO with unsymmetrical salen ligands, HL. All of the synthesized ligands and complexes were characterized by various physicochemical methods. Also, the solid-state structures of [NiL], [NiL], and [NiL] were defined through single-crystal X-ray diffraction methods.

Monomeric copper(II) complexes with unsymmetrical salen environment: Synthesis, characterization and study of biological activities.

Three new ONNO-donor tetradentate unsymmetrical salen ligands were synthesized by using o-phenyl diamine with substituted salicylaldehydes followed by a two-step reaction methodology. These three ligands by reaction with Cu(OAc).4HO produced three new monomeric Cu(II) complexes, [Cu(L)] (1-3).

Hydrolytically Stable Ti-Hydrazone-Based Metallodrugs: Protein Interaction and Anticancer Potential.

In this work, three titanium(IV) [Ti(L)] (-) complexes have been reported using three different tridentate dibasic ONO donor hydrazone ligands, pyridine-4-carboxylic acid (3-ethoxy-2-hydroxybenzylidene)-hydrazide (HL), furan-2-carboxylic acid (3-ethoxy-2-hydroxybenzylidene)-hydrazide (HL), and thiophene-2-carboxylic acid (3-ethoxy-2-hydroxybenzylidene)-hydrazide (HL) tethered with heterocyclic moieties. Elemental analysis, FT-IR, UV-vis, NMR, HR-ESI-MS, and single-crystal X-ray analysis have been used to characterize HL and -. In solid structures of -, two ligand molecules with NO donor sets give distorted octahedral geometries to the metal center.

Recent Advances in Mitochondria-Localized Luminescent Ruthenium(II) Metallodrugs as Anticancer Agents.

Presently, the most effective way to transport drugs specifically to mitochondria inside the cells is of pharmacophoric interest, as mitochondria are recognized as one of the most important targets for new drug design in cancer diagnosis. To date, there are many reviews covering the photophysical, photochemical, and anticancer properties of ruthenium(II) based metallodrugs owing to their high interest in biological applications. There are, however, no reviews specifically covering the mitochondria-localized luminescent Ru(II) complexes and their subsequent mitochondria-mediated anticancer activities.

Recent advancements of fluorescent tin(IV) complexes in biomedical molecular imaging.

In the last few years, tin(IV) complexes have emerged as very attractive candidates in the field of molecular imaging due to their unique photophysical properties. Despite the few reviews published to date covering the chemistry of organotin and tin complexes and their cytotoxic potential, there are no reviews devoted to their live cell imaging properties. Therefore, this feature article summarizes the discussion of the fundamental photophysical properties of fluorescent tin metal complexes focusing on their recent advances in "biomedical molecular imaging".

Kink distortion of the pseudo- axis in pseudotetrahedral [NO] bis-chelate cobalt(II) single-ion magnets leads to increased magnetic anisotropy.

Two new mononuclear cobalt(II) complexes with the general formula [Co(L)] (1 and 2) were synthesized using bidentate Schiff base ligands with NO donor set, namely, 2-(benzothiazole-2-ylimino)methyl-5-(diethylamino)phenol (HL1) and its methyl substituted derivative 2-(6-methylbenzothiazole-2-ylimino)methyl-5-(diethylamino)phenol (HL2). X-ray structure analysis reveals a distorted pseudotetrahedral coordination sphere at the cobalt(II) ion, that cannot be described by a simple twisting of the two ligand chelate planes with respect to each other, which would imply a rotation about the pseudo- axis of the complex. Such a pseudo-rotation axis would approximately be colinear with the two vectors defined by the cobalt ion and the two centroids of the chelate ligands, where the angle between the two vectors would be 180° in an ideal pseudotetrahedral arrangement.

A Series of Non-Oxido V Complexes of Dibasic ONS Donor Ligands: Solution Stability, Chemical Transformations, Protein Interactions, and Antiproliferative Activity.

A series of mononuclear non-oxido vanadium(IV) complexes, [V(L)] (), featuring tridentate bi-negative ONS chelating S-alkyl/aryl-substituted dithiocarbazate ligands HL, are reported. All the synthesized non-oxido V compounds are characterized by elemental analysis, spectroscopy (IR, UV-vis, and EPR), ESI-MS, as well as electrochemical techniques (cyclic voltammetry). Single-crystal X-ray diffraction studies of - reveal that the mononuclear non-oxido V complexes show distorted octahedral ( and ) or trigonal prismatic () arrangement around the non-oxido V center.

LVO-Ethyl Maltol-Based Metallodrugs (L = Tridentate ONO Ligands): Hydrophobicity, Hydrolytic Stability, and Cytotoxicity via ROS-Mediated Apoptosis.

Four new oxidovanadium [VOL(ema)] complexes (-) have been synthesized using tridentate binegative ONO donor ligands HL [HL: ()--(2-hydroxybenzylidene)furan-2-carbohydrazide; HL: ()--(4-(diethylamino)-2-hydroxybenzylidene)thiophene-2-carbohydrazide; HL: ()-2-(4-(diethylamino)-2-hydroxybenzylideneamino)-4-methylphenol; HL: ()-2-(3-ethoxy-2-hydroxybenzylideneamino)-4-methylphenol] and ethyl maltol (Hema) as a bidentate uninegative coligand and characterized by CHNS analysis, IR, UV-vis, NMR, and HR-ESI-MS methods. The structures of , , and are confirmed by single-crystal X-ray analysis. The hydrophobicity and hydrolytic stability of the complexes are tested using NMR and HR-ESI-MS and correlated with their observed biological activities.

Ruthenium(II)-Dithiocarbazates as Anticancer Agents: Synthesis, Solution Behavior, and Mitochondria-Targeted Apoptotic Cell Death.

The reaction of the Ru(PPh ) Cl with HL -OH (-OH stands for the oxime hydroxyl group; HL -OH=diacetylmonoxime-S-benzyldithiocarbazonate; HL -OH=diacetylmonoxime-S-(4-methyl)benzyldithiocarbazonate; and HL -OH=diacetylmonoxime-S-(4-chloro)benzyl-dithiocarbazonate) gives three new ruthenium complexes [Ru (L -H)(PPh ) Cl] (1-3) (-H stands for imine hydrogen) coordinated with dithiocarbazate imine as the final products. All ruthenium(II) complexes (1-3) have been characterized by elemental (CHNS) analyses, IR, UV-vis, NMR ( H, C, and P) spectroscopy, HR-ESI-MS spectrometry and also, the structure of 1-2 was further confirmed by single crystal X-ray crystallography. The solution/aqueous stability, hydrophobicity, DNA interactions, and cell viability studies of 1-3 against HeLa, HT-29, and NIH-3T3 cell lines were performed.

Mitochondria-Targeted Luminescent Organotin(IV) Complexes: Synthesis, Photophysical Characterization, and Live Cell Imaging.

Five fluorescent ONO donor-based organotin(IV) complexes, (), were synthesized by the one-pot reaction method and fully characterized spectroscopically including the single-crystal X-ray diffraction studies of . Detailed photophysical characterization of all compounds was performed. All the compounds exhibited high luminescent properties with a quantum yield of 17-53%.

Recent advancements on decarbonylation reactions assisted by Ru-complexes: Synthetic and mechanistic approach.

This frontier article covers the recent advancements in ruthenium complex catalysed decarbonylation reactions of different types of carbonyl compounds and provides a direction towards the mechanistic understanding. The mechanistic pathways provide new strategies for the use of appropriate ruthenium-catalysts, increase the substrate scope, and help in the synthesis of new complexes having multiple functionalities. The content of the article is categorized on the basis of the use of substrates.

New mixed ligand oxidovanadium(IV) complexes: Solution behavior, protein interaction and cytotoxicity.

Herein we report the synthesis of five new mononuclear mixed ligand oxidovanadium(IV) complexes [VO(L)(L)] (1-5) with tridentate O,N,O-donor aroylhydrazones as main ligand (HL) and N,N-chelating 2,2'-bipyridine (bipy) and 1,10-phenanthroline (phen) as co-ligand (L). The complexes were characterized by elemental and thermogravimetric analysis (TGA), IR, UV-vis, and electron paramagnetic resonance (EPR) spectroscopy, electrospray ionization-mass spectrometry (ESI-MS) and cyclic voltammetry (CV). The structure of 1-5 was confirmed by single crystal X-ray analysis and also optimized by density functional theory (DFT) methods.

Evaluation of DNA/BSA interaction and in vitro cell cytotoxicity of μ-oxido bridged divanadium(V) complexes containing ONO donor ligands.

Two new μ-oxido bridged divanadium (V) complexes, [VO(L)] (1 and 2) have been synthesized using bi-negative tridentate ONO-donor ligands, HL (HL = 4-tert-butyl-2-[[[3,5-di-tert-butyl-2-hydroxyphenyl]methylene]amino]phenol and HL = 5-bromo-2-[[[4-(diethylamino)-2-hydroxyphenyl]methylene]amino]phenol). The synthesized ligands and complexes have been characterized through FT-IR, UV-vis, NMR, and HR-ESI-MS techniques. Single crystal X-ray crystallography data confirmed distorted square pyramidal geometry for both the complexes.

Dithiocarbazate based oxidomethoxidovanadium(V) and mixed-ligand oxidovanadium(IV) complexes: Study of solution behavior, DNA binding, and anticancer activity.

In this work, one oxidomethoxidovanadium(V) [VO(L)(OMe)] (1) and two mixed-ligand oxidovanadium(IV) [VO(L)(phen)] (2), and [VO(L)(bipy)] (3) complexes have been synthesized using a tridentate bi-negative ONS donor dithiocarbazate as main ligand, HL [where, HL = S-benzyl-3-(2-hydroxy-3-ethoxyphenyl)methylenedithiocarbazate] along with 1,10-phenanthroline (phen) (for 2) and 2,2'-bipyridine (bipy) (for 3) as co-ligands. The ligand and complexes have been characterised by FT-IR, UV-vis, NMR, and HR-ESI-MS techniques. Distorted square pyramidal for 1, and distorted octahedral geometry for 2 and 3 was confirmed by single crystal X-ray crystallography.

Mo(VI) Potential Metallodrugs: Explaining the Transport and Cytotoxicity by Chemical Transformations.

The transport and cytotoxicity of molybdenum-based drugs have been explained with the concept of chemical transformation, a very important idea in inorganic medicinal chemistry that is often overlooked in the interpretation of the biological activity of metal-containing systems. Two monomeric, [MoO(L)(MeOH)] () and [MoO(L)(EtOH)] (), and two mixed-ligand dimeric MoO species, [{MoO(L)}(μ-4,4'-bipy)] (-), were synthesized and characterized. The structures of the solid complexes were solved through SC-XRD, while their transformation in water was clarified by UV-vis, ESI-MS, and DFT.

Water-Soluble Dioxidovanadium(V) Complexes of Aroylhydrazones: DNA/BSA Interactions, Hydrophobicity, and Cell-Selective Anticancer Potential.

Five new anionic aqueous dioxidovanadium(V) complexes, [{VOL}A(HO)] (-), with the aroylhydrazone ligands pyridine-4-carboxylic acid (3-ethoxy-2-hydroxybenzylidene)hydrazide (HL) and furan-2-carboxylic acid (3-ethoxy-2-hydroxybenzylidene)hydrazide (HL) incorporating different alkali metals (A = Na, K, Cs) as countercation were synthesized and characterized by various physicochemical techniques. The solution-phase stabilities of - were determined by time-dependent NMR and UV-vis, and also the octanol/water partition coefficients were obtained by spectroscopic techniques. X-ray crystallography of - confirmed the presence of vanadium(V) centers coordinated by two -oxido-O atoms and the O, N, and O atoms of a dianionic tridentate ligand.

Protein binding and cytotoxic activities of monomeric and dimeric oxido-vanadium(V) salan complexes: Exploring the solution behavior of monoalkoxido-bound oxido-vanadium(V) complex.

Three ONNO donor tetradentate diamino bis(phenolato) "salan" ligands, N, N'-dimethyl-N, N'-bis-(5-chloro-2-hydroxy-3-methyl-benzyl)-1,2-diaminoethane (HL), N, N'-dimethyl-N, N'-bis-(5-chloro-2-hydroxy-3-isopropyl-6-methyl-benzyl)-1,2-diamino-ethane (HL) and N, N'-bis-(5-chloro-2-hydroxy-3-isopropyl-6-methyl-benzyl)-1,2-diaminocyclohexane (HL) have been synthesized by following Mannich condensation reaction. Reaction of these ligands with their corresponding vanadium metal precursors gave one oxidomethoxidovanadium(V) [VOL(OCH)] (1) and two monooxido-bridged divanadium (V, V) complexes [VOL](μ-O) (2-3). The complexes were characterized by IR, UV-vis, NMR and ESI mass spectrometry.

Probing CO Generation through Metal-Assisted Alcohol Dehydrogenation in Metal-2-(arylazo)phenol Complexes Using Isotopic Labeling (Metal = Ru, Ir): Synthesis, Characterization, and Cytotoxicity Studies.

The reaction of 2-{2-(benzo[1,3]dioxol-5-yl)- diazo}-4-methylphenol (HL) with [Ru(PPh)Cl] in ethanol resulted in the carbonylated ruthenium complex [RuL(PPh)(CO)] (), wherein metal-assisted decarbonylation via in situ ethanol dehydrogenation is observed. When the reaction was performed in acetonitrile, however, the complex [RuL(PPh)(CHCN)] () was obtained as the main product, probably by trapping of a common intermediate through coordination of CHCN to the Ru(II) center. The analogous reaction of HL with [Ir(PPh)Cl] in ethanol did not result in ethanol decarbonylation and instead gave the organoiridium hydride complex [IrL(PPh)(H)] ().

New V, VO, VO, and VO Systems: Exploring their Interconversion in Solution, Protein Interactions, and Cytotoxicity.

The synthesis and characterization of one oxidoethoxidovanadium(V) [VO(L)(OEt)] () and two nonoxidovanadium(IV) complexes, [V(L)] ( and ), with aroylhydrazone ligands incorporating naphthalene moieties, are reported. The synthesized oxido and nonoxido vanadium complexes are characterized by various physicochemical techniques, and their molecular structures are solved by single crystal X-ray diffraction (SC-XRD). This revealed that in the geometry around the vanadium atom corresponds to a distorted square pyramid, with a ON coordination sphere, whereas that of the two nonoxido V complexes and corresponds to a distorted trigonal prismatic arrangement with a ON coordination sphere around each "bare" vanadium center.

Polynuclear zinc(II) complexes of thiosemicarbazone: Synthesis, X-ray structure and biological evaluation.

Two new dimeric Zn(II) ([{ZnL(DMSO)}]·DMSO (1), [{ZnLCl}] (2)) and a novel tetrameric Zn(II) complex ([(ZnL)(μ-OAc)(μ-O)] (3)), where HL = 4-(p-methoxyphenyl) thiosemicarbazone of o-hydroxynapthaldehyde, HL = 4-(p-methoxyphenyl)thiosemicarbazone of benzoyl pyridine and HL = 4-(p-chlorophenyl)thiosemicarbazone of o-vanillin are reported. Ligands and their complexes were characterized by spectroscopic and single crystal X-ray diffraction techniques. In addition, the complexes exhibited good binding affinity towards HSA (10 M), which is supported by their ability to quench the tryptophan fluorescence emission spectra of HSA.

Chemistry of mixed-ligand oxidovanadium(IV) complexes of aroylhydrazones incorporating quinoline derivatives: Study of solution behavior, theoretical evaluation and protein/DNA interaction.

A series of eight hexacoordinated mixed-ligand oxidovanadium(IV) complexes [VO(L)(L)] (1-8), where L = L - L are four differently substituted ONO donor aroylhydrazone ligands and L are N,N-donor bases like 2,2'-bipyridine (bipy) (1, 3, 5 and 7) and 1,10-phenanthroline (phen) (2, 4, 6 and 8), have been reported. All synthesized complexes have been characterized by various physicochemical techniques and molecular structures of 1 and 6 were determined by X-ray crystallography. With a view to evaluate the biological activity of the VO species, the behavior of the systems VO/L, VO/L/bipy and VO/L/phen was studied as a function of pH in a mixture of HO/DMSO 50/50 (v/v).