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Metal complexes showing dual activity against cancer and bacterial infections are currently the focus of significant interest for their potential in treating life-threatening diseases. Aiming to investigate the impact of ligand substituents on these bioactivity properties of Group 11 d 10 metal complexes, we herein present a series of mononuclear Cu(I) and Ag(I) complexes featuring the bis-NH 2 -substituted heterocyclic thioamide dap2SH (=4,6-diaminopyrimidine-2-thione), namely [AgCl(dap2SH)(PPh 3 ) 2 ] (1), [CuBr(dap2SH)(PPh 3 ) 2 ] (2), [CuBr(dap2SH)(xantphos)] (3), [Ag(dap2S)(xantphos)] (4), and [Cu(dap2S)(xantphos)] (5) (xantphos = 4,5-bis(diphenylphosphino)-9,9-dimethylxanthene). Complexes were characterized by means of different physicochemical methods (i.e., single crystal X-ray diffraction as well as FTIR, NMR, UV-Vis and fluorescence spectroscopy), and studied in-vitro for their antibacterial and anticancer activity against a variety of bacterial strains and cancer cell lines. Complexes 1-3 effectively inhibited both Gram (+) and Gram (-) bacterial growth, while cellular uptake studies for the most potent complex 1 against E. coli bacteria revealed the accumulation of Ag(I) ions in the periplasm of the bacteria. A high anti-proliferative effect was observed for 1 and 5 against A549, MCF7 and PC3 cancer cell lines, with 1 being capable of inducing apoptosis in A549 cells, as suggested by flow cytometry analysis. DNA interaction studies revealed the capacity of 1 to intercalate between base-pairs of CT DNA. All complexes had a moderate-to-high capacity to scavenge free radicals preventing oxidative stress. Molecular docking calculations, in combination with the experimentally obtained data, provided insights for potential mechanisms of the bioactivity of the complexes., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Masson SAS. All rights reserved.)

Fourteen cobalt(II) complexes with the non-steroidal anti-inflammatory drugs sodium meclofenamate, tolfenamic acid, mefenamic acid, naproxen, sodium diclofenac, and diflunisal were prepared in the presence or absence of a series of nitrogen-donors (namely imidazole, pyridine, 3-aminopyridine, neocuproine, 2,2'-bipyridine, 1,10-phenanthroline and 2,2'-bipyridylamine) as co-ligands and were characterised by spectroscopic and physicochemical techniques. Single-crystal X-ray crystallography was employed to determine the crystal structure of eight complexes. The biological profile of the complexes was investigated regarding their interaction with serum albumins and DNA, and their antioxidant potency. The interaction of the compounds with calf-thymus DNA takes place via intercalation. The ability of the complexes to cleave pBR322 plasmid DNA at the concentration of 500 μM is rather low. The complexes demonstrated tight and reversible binding to human and bovine serum albumins and the binding site of bovine serum albumin was also examined. In order to assess the antioxidant activity of the compounds, the in vitro scavenging activity towards free radicals, namely 1,1-diphenyl-picrylhydrazyl and 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid), and their ability to reduce H 2 O 2 were studied.

Anthranilic acids, salicylaldehydes and arylboronic acids reacted in EtOH/H 2 O (1/3) at 150 °C under microwave irradiation for 1 h to give, in excellent yields and purity, twenty-three bridgehead bicyclo[4.4.0]boron heterocycles via one-pot, three-component green synthesis. The scope and the limitations of the reactions are discussed in terms of the substitution of ten different anthranilic acids, three salicylaldehydes and three arylboronic acids. The replacement of salicylaldehyde with o -hydroxyacetophenone demanded a lipophilic solvent for the reaction to occur. Eight novel derivatives were isolated following crystallization in a toluene-containing mixture that included molecular sieves. The above one-pot, three-component reactions were completed under microwave irradiation at 180 °C within 1.5 h, thus avoiding the conventional prolonged heating reaction times and the use of a Dean-Stark apparatus. All derivatives were studied for their affinity to calf thymus DNA using proper techniques like viscosity and UV-vis spectroscopy, where DNA-binding constants were found in the range 2.83 × 10 4 -8.41 × 10 6 M -1 . Ethidium bromide replacement studies using fluorescence spectroscopy indicated Stern-Volmer constants between 1.49 × 10 4 and 5.36 × 10 4 M -1 , whereas the corresponding quenching constants were calculated to be between 6.46 × 10 11 and 2.33 × 10 12 M -1 s -1 . All the above initial experiments show that these compounds may have possible medical applications for DNA-related diseases.

Four erbium(III) complexes with the fluoroquinolones enrofloxacin, levofloxacin, flumequine and sparfloxacin as ligands were synthesized and characterized by a wide range of physicochemical and spectroscopic techniques as well as single-crystal X-ray crystallography. The compounds were evaluated for their activity against the bacterial strains Staphylococcus aureus, Bacillus subtilis, Escherichia coli and Xanthomonas campestris, which was higher than that of the corresponding free quinolones. The interaction mode of the complexes with calf-thymus DNA is via intercalation, as suggested by diverse studies such as UV-vis spectroscopy, DNA-viscosity measurements and competitive studies with ethidium bromide. Fluorescence emission spectroscopy revealed the high affinity of the complexes for bovine and human serum albumin and the determined binding constants suggested a tight and reversible binding of the compounds with both albumins., Competing Interests: Declaration of competing interest There are no conflicts to declare., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Copper(II) complexes with an α-diimine show a wide variety of biological activities, such as antibacterial, antifungal, antioxidant and anticancer. In this work, we synthesized and structurally characterized two novel Cu(II) complexes with methyl 3-formyl-4-hydroxybenzoate (HL) and α-diimines: 2,2'-bipyridine (bipy) and 1,10-phenanthroline (phen). Crystal structure analysis shows that the formulas of the compounds are [Cu(bipy)(L)(BF 4 )] (1) and [Cu(phen)(L)(H 2 O)](BF 4 )·H 2 O (2), with BF 4 - as a ligand in complex 1, which is rarely coordinated to metals. Both complexes have a square pyramidal geometry, while DFT calculations showed that the most stable structures of complexes 1 and 2 in a water/DMSO mixture are square-planar derivatives [Cu(bipy)(L)] + and [Cu(phen)(L)] + . The antibacterial activity of compounds was evaluated in vitro on four Gram-negative and four Gram-positive bacterial strains. Complex 2 showed greater antibacterial activity towards all bacterial strains comparable to the control compound Amikacin. Complex 2 exerted a strong cytotoxic effect against the tested cancer cell lines (IC 50 values ranging from 0.32 to 0.44 μM). Both complexes caused apoptotic cell death in HeLa cells and a noticeable in vitro antiangiogenic effect. In the concentration range of 5 to 100 μM, the complexes showed the absence of a genotoxic effect and displayed a protective effect against oxidative DNA damage induced by H 2 O 2 in human peripheral blood cells. The interaction between the compounds and calf-thymus DNA was evaluated by diverse techniques suggesting a tight binding, which was also confirmed by molecular docking. In addition, it was found that the complexes bind tightly and reversibly to bovine and human serum albumin.

Four neutral and six cationic nickel(II) complexes of the substituted salicylaldehydes (X-diCl-saloH), namely 3,5-dichloro-salicylaldehyde (3,5-diCl-saloH) and 5-fluoro-salicylaldehyde (5-F-saloH), were synthesized in the absence or presence of the N,N'-donors 1,10-phenanthroline (phen), 2,9-dimethyl-1,10-phenanthroline (neoc), or 2,2'-bipyridylamine (bipyam) as co-ligands and were characterized by various techniques. The obtained complexes bear the general formulas [Ni(X-salo) 2 (H 2 O) 2 ], [Ni(3,5-diCl-salo) 2 (neoc/phen)] and [Ni(X-salo)(N,N'-donor) 2 ](PF 6 ). The crystal structures of three complexes were determined by single-crystal X-ray crystallography revealing a bidentate coordination of the salicylaldehydes. The interaction of the compounds with calf-thymus DNA was studied by diverse techniques which revealed an intercalative interaction for the neutral complexes [Ni(X-salo) 2 (H 2 O) 2 ] and [Ni(3,5-diCl-salo) 2 (neoc/phen)]and the co-existence of electrostatic interactions for the cationic complexes [Ni(X-salo)(N,N'-donor) 2 ](PF 6 ). The compounds bind tightly and reversibly to serum albumins. The antibacterial activity of the compounds was investigated against Staphylococcus aureus ATCC 6538, Bacillus subtilis ATCC 6633, Escherichia coli NCTC 29,212 and Xanthomonas campestris ATCC 1395 and the complexes bearing neoc as co-ligand proved the most potent., Competing Interests: Declaration of Competing Interest There are no conflicts to declare., (Copyright © 2023 Elsevier Inc. All rights reserved.)

A series of copper(II), nickel(II) and cobalt(II) complexes with the non-steroidal anti-inflammatory drug oxaprozin (Hoxa) have been synthesized and characterized by diverse techniques. The crystal structures of two copper(II) complexes, namely the dinuclear complex [Cu 2 (oxa) 4 (DMF) 2 ] (1) and the polymeric complex {[Cu 2 (oxa) 4 ]·2MeOH·0.5MeOH} 2 (12) were determined by single-crystal X-ray diffraction studies. In order to evaluate in vitro the antioxidant activity of the resultant complexes, their scavenging ability towards 1,1-diphenyl-picrylhydrazyl (DPPH), hydroxyl and 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) radicals was investigated revealing their high effectiveness against these radicals. The binding of the complexes to bovine serum albumin and human serum albumin was examined and the corresponding determined albumin-binding constants showed a tight and reversible interaction. The interaction of the complexes with calf-thymus DNA was monitored by diverse techniques including UV-vis spectroscopy, cyclic voltammetry, DNA-viscosity measurements and competitive studies with ethidium bromide. Intercalation may be proposed as the most possible DNA-interaction mode of the complexes., Competing Interests: Declaration of Competing Interest There are no conflicts to declare., (Copyright © 2023 Elsevier Inc. All rights reserved.)

Five erbium(III) complexes with salicylaldehyde (saloH for 1), and mono- (5-X-saloH; X = NO 2 and Me for 2 and 3, respectively) or di-substituted salicylaldehydes (3,5-diX-saloH; X = Cl and Br for 4 and 5, respectively) were synthesized and characterized by physicochemical and spectroscopic techniques and single-crystal X-ray crystallography. All five complexes have the general formula [Er(deprotonated salicylaldehyde) 3 (MeOH)(H 2 O)]. The structure of complexes [Er(3,5-diCl-salo) 3 (MeOH)(H 2 O)]·1.5MeOH (complex 4) and [Er(3,5-diBr-salo) 3 (MeOH)(H 2 O)]·1.75MeOH (complex 5) were verified by single-crystal X-ray crystallography. The evaluation of antioxidant activity of the complexes was focused on their ability to scavenge 1,1-diphenyl-picrylhydrazyl and 2,2'-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid) free radicals and to reduce H 2 O 2 . The interaction of the complexes with calf-thymus DNA was investigated by UV-vis spectroscopy, viscosity measurements and via competitive studies with ethidium bromide in order to evaluate the possible DNA-binding mode and to determine the corresponding DNA-binding constants. The affinity of the complexes for bovine and human serum albumins was explored by fluorescence emission spectroscopy and the corresponding binding constants were determined., Competing Interests: Declaration of Competing Interest There are no conflicts to declare., (Copyright © 2023 Elsevier Inc. All rights reserved.)

A facile experimental protocol for the synthesis of poly(ethylene glycol)-modified (PEGylated) gold nanorods (AuNRs@PEG) is presented as well as an effective drug loading procedure using the non-steroidal anti-inflammatory drug (NSAID) naproxen (NAP). The interaction of AuNRs@PEG and drug-loaded AuNRs (AuNRs@PEG@NAP) with calf-thymus DNA was studied at a diverse temperature revealing different interaction modes; AuNRs@PEG may interact via groove-binding and AuNRs@PEG@NAP may intercalate to DNA-bases. The cleavage activity of the gold nanoparticles for supercoiled circular pBR322 plasmid DNA was studied by gel electrophoresis while their affinity for human and bovine serum albumins was also evaluated. Drug-release studies revealed a pH-sensitive behavior with a release up to a maximum of 24% and 33% NAP within the first 180 min at pH = 4.2 and 6.8, respectively. The cytotoxicity of AuNRs@PEG and AuNRs@PEG@NAP was evaluated against MCF-7 and MDA-MB-231 breast cancer cell lines. The development of AuNRs as an efficient non-steroidal anti-inflammatory drugs (NSAIDs) delivery system for chemotherapy is still in its infancy. The present work can shed light and inspire other research groups to work in this direction., Competing Interests: The authors declare no conflict of interest.

One the main research goals of bioinorganic chemists is the synthesis of novel coordination compounds possessing biological potency. Within this context, three novel iron(III) complexes with the non-steroidal anti-inflammatory drugs diflunisal and diclofenac in the presence or absence of the nitrogen donors 1,10-phenanthroline or pyridine were isolated and characterized by diverse techniques. The complexes were evaluated for their ability to scavenge in vitro free radicals such as hydroxyl, 1,1-diphenyl-2-picrylhydrazyl and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) radicals, revealing their selective potency towards hydroxyl radicals. The in vitro inhibitory activity of the complexes towards the enzymes acetylcholinesterase and butyrylcholinesterase was evaluated, and their potential to achieve neuroprotection appeared promising. The interaction of the complexes with calf-thymus DNA was examined in vitro, revealing their ability to intercalate in-between DNA nucleobases. The affinity of the complexes for serum albumins was evaluated in vitro and revealed their tight and reversible binding.

Naproxen (6-methoxy-α-methyl-2-naphthaleneacetic acid), 1-naphthylacetic acid, 2-naphthylacetic acid and 1-pyreneacetic acid are derivatives of acetic acid bearing a naphthalene-based ring. In the present review, the coordination compounds of naproxen, 1- or 2-naphthylacetato and 1-pyreneacetato ligands are discussed in regard to their structural features (nature and nuclearity of metal ions and coordination mode of ligands), their spectroscopic and physicochemical properties and their biological activities.

A set of arylazo sulfones, known to undergo N-S bond cleavage upon light exposure, has been synthesized, and their activity in the dark and upon irradiation towards DNA has been investigated. Their interaction with calf-thymus DNA has been examined, and the significant affinity observed (most probably due to DNA intercalation) was analyzed by means of molecular docking "in silico" calculations that pointed out polar contacts, mainly via the sulfonyl moiety. Incubation with plasmid pBluescript KS II revealed DNA cleavage that has been studied over time and concentration. UV-A irradiation considerably improved DNA damage for most of the compounds, whereas under visible light the effect was slightly lower. Moving to in vitro experiments, irradiation was found to slightly enhance the death of the cells in the majority of the compounds. Naphthylazosulfone 1 showed photo-disruptive effect under UV-A irradiation (IC 50 ~13 μΜ) followed by derivatives 14 and 17 (IC 50 ~100 μΜ). Those compounds were irradiated in the presence of two non-cancer cell lines and were found equally toxic only upon irradiation and not in the dark. The temporal and spatial control of light, therefore, might provide a chance for these novel scaffolds to be useful for the development of phototoxic pharmaceuticals.

Ag(I) coordination compounds have recently attracted much attention as antiproliferative and antibacterial agents against a wide range of cancer cell lines and pathogens. The bioactivity potential of these complexes depends on their structural characteristics and the nature of their ligands. Herein, we present a series of four Ag(I) coordination compounds bearing as ligands the CH 3 -substituted thiadiazole-based thioamide 5-methyl-1,3,4-thiadiazole-2-thiol (mtdztH) and phosphines, i.e., [AgCl(mtdztH)(PPh 3 ) 2 ] ( 1 ), [Ag(mtdzt)(PPh 3 ) 3 ] ( 2 ), [AgCl(mtdztH)(xantphos)] ( 3 ), and [AgmtdztH)(dppe)(NO 3 )] n ( 4 ), where xantphos = 4,5-bis(diphenylphosphino)-9,9-dimethylxanthene and dppe = 1,2-bis(diphenylphosphino)ethane, and the assessment of their in vitro antibacterial and anti-cancer efficiency. Among them, diphosphine-containing compounds 3 and 4 were found to exhibit broad-spectrum antibacterial activity characteristics against both Gram-(+) and Gram-(-) bacterial strains, showing high in vitro bioactivity with IC 50 values as low as 4.6 μΜ. In vitro cytotoxicity studies against human ovarian, pancreatic, lung, and prostate cancer cell lines revealed the strong cytotoxic potential of 2 and 4 , with IC 50 values in the range of 3.1-24.0 μΜ, while 3 and 4 maintained the normal fibroblast cells' viability at relatively higher levels. Assessment of these results, in combination with those obtained for analogous Ag(I) complexes bearing similar heterocyclic thioamides, suggest the pivotal role of the substituent groups of the thioamide heterocyclic ring in the antibacterial and anti-cancer efficacy of the respective Ag(I) complexes. Compounds 1 - 4 exhibited moderate in vitro antioxidant capacity for free radicals scavenging, as well as reasonably strong ability to interact with calf-thymus DNA, suggesting the likely implication of these properties in their bioactivity mechanisms. Complementary insights into the possible mechanism of their anti-cancer activity were provided by molecular docking calculations, exploring their ability to bind to the overexpressed fibroblast growth factor receptor 1 (FGFR1), affecting cancer cells' functionalities.

Eight copper(II) complexes of 3,5-dichloro-salicyladehyde or 3,5-dibromo-salicyladehyde (3,5-diX-saloH, X = Br or Cl) were synthesized in the absence or presence of a N,N'-donor co-ligand such as 2,2'-bipyridylamine, 1,10-phenanthroline, or 2,2'-bipyridine. The resultant compounds were formulated as [Cu(3,5-diX-salo) 2 (MeOH) 2 ] (1-2) and [Cu(3,5-diX-salo)(N,N'-donor)Cl] (3-8) and were characterized by diverse techniques. The crystal structures of three complexes were determined by single-crystal X-ray crystallography. Diverse techniques were employed in order to investigate the interaction of the complexes with calf-thymus DNA which showed intercalation as the most possible mode of their interaction. The affinity of the complexes for bovine serum albumin and human serum albumin was evaluated by fluorescence emission spectroscopy in order to calculate the binding constants which suggested a tight and reversible binding. SYNOPSIS: A series of copper(II) complexes with 3,5-dihalogen-substituted salicylaldehydes as ligands were isolated and characterized. In vitro biological studies showed the intercalation of the compounds with calf-thymus DNA and their tight and reversible binding with serum albumins., Competing Interests: Declaration of Competing Interest There are no conflicts to declare., (Copyright © 2022 Elsevier Inc. All rights reserved.)

The synthesis, characterization and biological profile (antioxidant capacity, interaction with calf-thymus DNA and serum albumins) of five neutral copper(II) complexes of 5-fluoro-salicylaldehyde in the absence or presence of the N , N' -donor co-ligands 2,2'-bipyridylamine, 2,9-dimethyl-1,10-phenanthroline, 1,10-phenanthroline and 2,2'-bipyridine are presented herein. The compounds were characterized by physicochemical and spectroscopic techniques. The crystal structures of four complexes were determined by single-crystal X-ray crystallography. The ability of the complexes to scavenge 1,1-diphenyl-picrylhydrazyl and 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) radicals and to reduce H 2 O 2 was investigated in order to evaluate their antioxidant activity. The interaction of the compounds with calf-thymus DNA possibly takes place via intercalation as suggested by UV-vis spectroscopy and DNA-viscosity titration studies and via competitive studies with ethidium bromide. The affinity of the complexes with bovine and human serum albumins was examined by fluorescence emission spectroscopy revealing the tight and reversible binding of the complexes with the albumins.

Five neutral zinc(II) complexes of 3-bromo-5-chloro-salicylaldehyde (3-Br-5-Cl-saloH) were synthesized in the absence or presence of the nitrogen-donor co-ligands 2,2'-bipyridine (bipy), 1,10-phenanthroline (phen), 2,9-dimethyl-1,10-phenanthroline (neoc), or 2,2'-bipyridylamine (bipyam) and were characterized by various techniques. The obtained complexes were [Zn(3-Br-5-Cl-salo) 2 (H 2 O) 2 ] (1), [Zn(3-Br-5-Cl-salo) 2 (bipy)] (2), [Zn(3-Br-5-Cl-salo) 2 (phen)] (3), [Zn(3-Br-5-Cl-salo) 2 (neoc)] (4) and [Zn(3-Br-5-Cl-salo) 2 (bipyam)] (5). The crystal structures of complexes 1 and 3 were determined by single-crystal X-ray crystallography. The interaction of the compounds with calf-thymus DNA takes place via intercalation. The compounds may moderately cleave pBR322 plasmid DNA at a concentration of 500 μM. The compounds may bind tightly and reversibly to serum albumins. The antioxidant activity of the compounds was examined towards 1,1-diphenyl-picrylhydrazyl and 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) radicals and H 2 O 2 . The antimicrobial potency of the compounds was investigated against Staphylococcus aureus ATCC 6538, Bacillus subtilis ATCC 6633, Escherichia coli NCTC 29212 and Xanthomonas campestris ATCC 1395.

Two novel halogenated (Br- and F-) quinazoline derivatives, namely [( E )-4-(2-((6-bromopyridin-2-yl)methylene)hydrazinyl)quinazoline] (L1) and [( E )-4-(2-((3-fluoropyridin-2-yl)methylene)hydrazinyl) quinazoline] (L2), were synthesized and characterized. Their interaction with a series of metal(II) ions (= Mn(II), Ni(II), Cu(II), Zn(II) and Cd(II)) resulted in the formation of six mononuclear complexes characterized by spectroscopic techniques and single-crystal X-ray crystallography. The complexes bear the formulae [Ni(L 1 ) 2 ](NO 3 ) 2 (1), [Zn(L 2 ) 2 ](NO 3 )(PF 6 ) (2), [Cd(L 2 )(H 2 O)(CH 3 OH)(NO 3 )](NO 3 ) (3), [Cu(L 2 )Cl 2 ] (4), [Ni(L 2 ) 2 ](NO 3 ) 2 (5) and [Mn(L 2 )(CH 3 OH)(Cl) 2 ] (6). The biological activity of the compounds was further evaluated in vitro regarding their interaction with calf-thymus DNA, their cleavage ability towards supercoiled circular pBR322 plasmid DNA in the absence or presence of irradiation at various wavelengths (UVA, UVB and visible light), their affinity to bovine serum albumin and their ability to scavenge 1,1-diphenyl-picrylhydrazyl and 2,2'-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid) radicals and to reduce H 2 O 2 . In silico molecular docking calculations were employed to study the behavior of the complexes towards calf-thymus DNA and bovine serum albumin.

A series of Mn(II) complexes of 5-nitro-salicyladehyde or substituted 2-hydroxy-phenones (HL) were synthesized in the absence or presence of a N,N'-donor co-ligand such as 2,2'-bipyridine, 1,10-phenanthroline, or 2,2'-bipyridylamine. The resultant coordination compounds were formulated as [Mn(L) 2 (CH 3 OH) 2 ] (1-3) and [Mn(L) 2 (N,N'-donor)] (4-14), respectively, and characterized by diverse techniques. The crystal structures of three complexes were determined by single-crystal X-ray crystallography. Diverse techniques were employed to study the interaction of the complexes with calf-thymus DNA and showed intercalation as the most possible mode of their tight interaction. The affinity of the complexes for bovine serum albumin was investigated by fluorescence emission spectroscopy in order to calculate the binding constants which suggested a tight and reversible binding., (Copyright © 2022 Elsevier Inc. All rights reserved.)

In this article, cytotoxicity, the mechanisms of cytotoxic activity, genotoxicity, and interaction with DNA and proteins, of two Cu(II) complexes with a salicylaldehyde derivative (4-(diethylamino)salicylaldehyde) and α-diimine (2,2'-bipyridine (bipy) and 1,10-phenanthroline (phen)) are reported. Both Cu(II) complexes performed cytotoxic effects against all tested malignant cell lines. Complexes exerted highest cytotoxicity against HeLa and A375 malignant cell lines. The cytotoxic activity of Cu(II) complex with phen as a α-diimine co-ligand was significantly higher in comparison with cytotoxic activity of Cu(II) complex with bipy. Pretreatment with specific inhibitors of caspase-3, caspase-8 or caspase-9, in order to clear up the mode of cell death triggered by two Cu(II) complexes in HeLa cells, indicated the ability of these complexes to induce apoptosis through activation of target caspases. Cu(II)-phen complex exhibited significant antioxidant activity compared with Cu(II)-bipy complex, and showed a better effect on reducing intracellular ROS levels in HeLa cells. Tested complexes did not display genotoxic potential in human peripheral blood leucocytes, but exhibited an antigenotoxic effect in post-treatment, after H 2 O 2 exposure. The study of the in vitro biological properties regarding their affinity towards CT (calf-thymus) DNA and serum albumins showed that the compounds can intercalate to CT DNA, and bind reversibly and tightly to the albumins. Molecular docking studies of the ability of compounds to bind to biomacromolecules are consistent with in vitro studies., (Copyright © 2022 Elsevier Inc. All rights reserved.)

Aminated silica hybrid, spin-crossover (SCO) nanoparticles (AmNPs) coupled with ( S )-naproxen (NAP) were proposed for potential drug nanocarriers through drug release experiments at various pH values. DNA- and albumin-binding studies were also carried out using diverse techniques in order to investigate the interaction of the nanoparticles with calf-thymus DNA and serum albumins and to determine the corresponding binding constants.

Five palladium(II) complexes of substituted salicylaldehydes (X-saloH, X = 4-Et 2 N (for 1 ), 3,5-diBr (for 2 ), 3,5-diCl (for 3 ), 5-F (for 4 ) or 4-OMe (for 5 )) bearing the general formula [Pd(X-salo) 2 ] were synthesized and structurally characterized. The crystal structure of complex [Pd(4-Et 2 N-salo) 2 ] was determined by single-crystal X-ray crystallography. The complexes can scavenge 1,1-diphenyl-picrylhydrazyl and 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) radicals and reduce H 2 O 2 . They are active against two Gram-positive ( Staphylococcus aureus and Bacillus subtilis ) and two Gram-negative ( Escherichia coli and Xanthomonas campestris ) bacterial strains. The complexes interact strongly with calf-thymus DNA via intercalation, as deduced by diverse techniques and via the determination of their binding constants. Complexes interact reversibly with bovine and human serum albumin. Complementary insights into their possible mechanisms of bioactivity at the molecular level were provided by molecular docking calculations, exploring in silico their ability to bind to calf-thymus DNA, Escherichia coli and Staphylococcus aureus DNA-gyrase, 5-lipoxygenase, and membrane transport lipid protein 5-lipoxygenase-activating protein, contributing to the understanding of the role complexes 1 - 5 can play both as antioxidant and antibacterial agents. Furthermore, in silico predictive tools have been employed to study the chemical reactivity, molecular properties and drug-likeness of the complexes, and also the drug-induced changes of gene expression profile (as protein- and mRNA-based prediction results), the sites of metabolism, the substrate/metabolite specificity, the cytotoxicity for cancer and non-cancer cell lines, the acute rat toxicity, the rodent organ-specific carcinogenicity, the anti-target interaction profiles, the environmental ecotoxicity, and finally the activity spectra profile of the compounds.

In recent years, there has been an increasing interest in the study of Ag(I) coordination compounds as potent antibacterial and anticancer agents. Herein, a series of Ag(I) complexes bearing phosphines and heterocyclic thioamide ligands with highly electronegative NH 2 - and CF 3 -group substituents, i.e. [AgCl(atdztH)(xantphos)] (1), [Ag(μ-atdztH)(DPEphos)] 2 (NO 3 ) 2 (2), [Ag(atdzt)(PPh 3 ) 3 ] (3), [Ag(μ-atdzt)(DPEphos)] 2 (4), and [Ag(μ-mtft)(DPEphos)] 2 (5), where atdztH = 5-amino-1,3,4-thiadiazole-2-thiol, mtftH = 4-methyl-5-(trifluoromethyl)-1,2,4-triazol-3-thiol, xantphos = 4,5-bis(diphenylphosphino)-9,9-dimethylxanthene, and DPEphos = bis(2-diphenylphosphino-phenyl)ether, were synthesized, and their in vitro antibacterial and anticancer properties were evaluated. Complexes 1-4 bearing the NH 2 -substituted thioamide exhibited moderate-to-high activity against S. aureus , B. subtilis , B. cereus and E. coli bacterial strains. A high antiproliferative activity was also observed for 1-3 against SKOV-3, Hup-T3, DMS114 and PC3 cancer cell lines (IC 50 = 4.0-11.7 μM), as well as some degree of selectivity against MRC-5 normal cells. Interestingly, 5 bearing the CF 3 -substituted thioamide is completely inactive in all bioactivity studies. Binding of 1-3 to drug-carrier proteins BSA and HSA is reasonably strong for their uptake and subsequent release to possible target sites. The three complexes show a significant in vitro antioxidant ability for scavenging free radicals, suggesting likely implication of this property in the mechanism of their bioactivity, but a low potential to destroy the double-strand structure of CT-DNA by intercalation. Complementary insights into possible bioactivity mechanisms were provided by molecular docking calculations, exploring the ability of complexes to bind to bacterial DNA gyrase, and to the overexpressed in the aforementioned cancer cells Fibroblast Growth Factor Receptor 1, affecting their functionalities.

In silico molecular docking studies, in vitro toxicity and in silico predictions on the biological activity profile, pharmacokinetic properties, drug-likeness, ADMET (absorption, distribution, metabolism, excretion, and toxicity) physicochemical pharmacokinetic data, and target proteins and toxicity predictions were performed on six copper(II) complexes with the non-steroidal anti-inflammatory drugs ibuprofen, loxoprofen, fenoprofen and clonixin as ligands, in order to investigate the ability of these complexes to interact with the key therapeutic target proteins of SARS-CoV-2 (Severe Acute Respiratory Syndrome Coronavirus 2) 3C-like cysteine main protease (3CLpro/M pro ), viral papain-like protease (PLpro), RNA-dependent RNA polymerase (RdRp), and non-structural proteins (Nsps) Nsp16-Nsp10 2'-O-methyltransferase complex, and their capacity to act as antiviral agents, contributing thus to understanding the role they can play in the context of coronavirus 2019 (COVID-19) pandemic. Cytotoxic activity against five human cancer and normal cell lines were also evaluated., (Copyright © 2022 Elsevier Inc. All rights reserved.)

A series of complexes of divalent transition metals (Cu(II), Mn(II), Zn(II), Co(II) and Ni(II)) with the quinolone antibacterial agent fleroxacin, in the absence or presence of an α -diimine such as 2,2'-bipyridine, 1,10-phenanthroline or 2,2'-bipyridylamine, were prepared and characterized. The complexes were characterized by various physicochemical and spectroscopic techniques and by single-crystal X-ray crystallography. The in vitro antibacterial activity of the complexes was studied against the bacterial strains Staphylococcus aureus , Bacillus subtilis and Xanthomonas campestris and was higher than that of free quinolone. The affinity of the complexes for bovine and human serum albumin was studied by fluorescence emission spectroscopy and the determined binding constants showed tight and reversible binding to the albumins. The interaction of the complexes with calf-thymus DNA was studied by various techniques, which showed that intercalation was the most plausible mode of interaction.

Five Zn(II) complexes with 3,5-dichloro-salicylaldehyde (3,5-diCl-saloH) in the absence or presence of N,N'-donor co-ligands (2,2'-bipyridine, 1,10-phenanthroline, 2,9-dimethyl-1,10-phenanthroline, or 2,2'-bipyridylamine) were synthesized and formulated as [Zn(3,5-diCl-salo) 2 (CH 3 OH) 2 ] (1) and [Zn(3,5-diCl-salo) 2 (N,N'-donor)] (2-5), respectively, and characterized by diverse techniques. The crystal structures of four complexes were determined by single-crystal X-ray crystallography. The ability of the compounds to scavenge 1,1-diphenyl-picrylhydrazyl and 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) radicals and to reduce H 2 O 2 was investigated. In addition, their antimicrobial profile against two Gram-positive and two Gram-negative bacterial strains were investigated. The affinity of the complexes for calf-thymus DNA was examined by diverse techniques, and the DNA-binding constants of the complexes were determined. The cleavage ability of the complexes towards supercoiled circular pBR322 plasmid DNA was examined by agarose gel electrophoretic experiments. The binding of the complexes with bovine and human serum albumins was investigated in order to determine the corresponding binding constants and the binding subdomain. In order to explain the described in vitro activity of the compounds and possibly establish a rational approach in the mechanism of action, molecular docking studies were adopted on the crystal structure of E. coli and S. aureus DNA-gyrase, 5-lipoxygenase, and 5-lipoxygenase-activating protein., (Copyright © 2022 Elsevier Inc. All rights reserved.)

Through the reaction of copper(II) acetate with nicotinamide (pyridine-3-carboxylic acid amide, niacinamide) and some derivatives of N-phenylanthranilic acid (fenamates), seven new mixed-ligand copper(II) compounds were isolated: [Cu(tolf-O)(tolf-O,O')nia-N) 2 (EtOH)] (1), [Cu(tolf-O)(tolf-O,O')(nia-N) 2 (MeOH)] (2), [Cu(meclf-O)(meclf-O,O')(nia-N) 2 (EtOH)] (3), [Cu(meclf-O)(meclf-O,O')(nia-N) 2 (MeOH)] (4), [Cu(meclf-O)(meclf-O,O')(nia-N) 2 (ACN)] (5), [Cu(mef-O)(mef-O,O')(nia-N) 2 (EtOH)] (6) and [Cu(mef-O)(mef-O,O')(nia-N) 2 (ACN)] (7) containing a molecule of relevant solvent as ligand in their primary crystal structure (tolf = tolfenamate, meclf = meclofenamate, mef = mefenamate, nia = nicotinamide, EtOH = ethanol, MeOH = methanol, ACN = acetonitrile). The structures of the complexes were determined by single-crystal X-ray analysis. The intermolecular interactions were studied by Hirshfeld surface analysis. The complexes were characterized by IR, UV-vis and EPR spectroscopy and their redox properties were determined by cyclic voltammetry. The interaction of the complexes with bovine serum albumin was studied by fluorescence emission spectroscopy and the albumin-binding constants of the compounds were calculated. The interaction of the complexes with calf-thymus DNA was monitored by diverse techniques (UV-vis spectroscopy, cyclic voltammetry, viscosity measurements) suggesting intercalation as the most possible mode of binding. DNA-competitive studies of the complexes with ethidium bromide were monitored by fluorescence emission spectroscopy. The cytotoxic effects of copper(II) complexes on lung carcinoma cells and healthy cells were determined by the MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] colorimetric technique., (Copyright © 2021 Elsevier Inc. All rights reserved.)