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Sodium salt of 4‐hydroxy‐3‐([2‐isonicotinoylhydrazineylidene]methyl)benzenesulfonate ligand (NaH2IH) was prepared, as an example of water‐soluble Schiff base ligands, by the condensation of isonicotinohydrazide with the sodium salt of 3‐formyl‐4‐ hydroxybenzenesulfonate. The chemical structure of the novel water‐soluble ligand and its complexes have been elucidated by analyzing the results of different spectroscopic and magnetic measurements. These structures were supported by the computational studies using density functional theory (DFT) technique. The ligand acts as mono‐negative bi‐dentate (ON) in [Cd(HIH)(H2O)Cl]2 complex, and as a tri‐negative tetra‐dentate (OONO) ligand in [Ce(IH)(H2O)2]2. In the [Cu(NaHIH)Cl]2.2H2O complex, NaH2IH behaves as mono‐negative tri‐dentate (ONN). Another mode of complexation displayed in [Ni(NaHIH)(H2O)Cl].2H2O dimer, whereas NaH2IH acts as a mono‐basic ON bi‐dentate. Based on the spectral data, one can assume a four‐coordinated tetrahedral geometry in case of all isolated complexes except Ce(III) one which has an octahedral geometry. The molecular structures and chemical geometries of the metal complexes were optimized and conformed using computational studies using DFT method. The outcomes of antioxidant activities reveal that the investigated compounds have good radical scavenging activity against ABTS and DPPH• radicals. The DNA binding ability of NaH2IH and its complexes has been examined by agarose gel electrophoresis methods. Wound healing was performed to test the antimetastatic activity of [Cd(HIH)(H2O)Cl]2 complex against MDA‐MB‐231 cancer cell line. Antimicrobial behavior of the compounds under study has been assessed against selected microorganism. [ABSTRACT FROM AUTHOR]

A water‐soluble hydrazone ligand bearing 2‐nicotinoylhydrazineylidene moiety, sodium 4‐hydroxy‐3‐([2‐nicotinoylhydrazineylidene]methyl) benzenesulfonate (NaH2NH), and its complexes with Co(II), Fe(III), and Mn(II) have been synthesized and characterized. The structure of the ligand and its complexes were analyzed using various spectroscopic techniques such as FT‐IR, 1H‐ and 13C‐NMR, EI‐mass, powder X‐ray diffraction, UV–visible spectra, and magnetic measurements. The infrared spectra indicated that the ligand behaves as a negatively charged bidentate ligand (ON) through the deprotonation of the enolic (OH) group and the azomethine (C=N) group in the [Co (NaHNH)2(H2O)4Cl2].3H2O complex. In the [Fe (NaNH)2(H2O)Cl].2H2O complex, the ligand behaves as bi‐negative tetradentate (O2N2) through the protonation of the enolic oxygen and the nitrogen atom of the azomethine group in two nicotinic hydrazone molecules. Another coordination type was observed for [Mn (NaNH)(H2O)3] complex in which NaH2NH acts as bi‐negative tridentate ONO through the nitrogen atom of the azomethine group, the protonated of enolic and phenolic groups. The fluorescence spectrum of the NaH2NH was found to be quenched upon addition of these Co(II) and Mn(II) ions. The antimicrobial results indicated that the Mn(II) complex exhibited the highest antibacterial potency against all targeted organisms. The results of antioxidants demonstrated that the complexes exhibited higher activity compared to the free ligand, indicating an enhancement of antioxidant activity through complexation. The tested substances established strong nuclease‐like activity at a high concentration of 7.5 mM, leading to the complete degradation of DNA as observed in agarose gel electrophoresis. This suggests that these compounds have the potential to serve as antitumor agents in vivo by inhibiting DNA replication in cancer cells and preventing tumor growth. The interaction of the isolated compounds with 1c14 and 6vj3 targets was discussed using molecular docking. [ABSTRACT FROM AUTHOR]

N‐(benzo[d]thiazol‐2‐ylcarbamothioyl)benzamide (H2L2) was synthesized as a novel thiosemicarbazide containing benzothiazole moiety, by the reaction of benzoyl isothiocyanate with 2‐aminobenzothiazole in benzene. The (H2L2) thiosemicarbazide and its isolated Cr(III), Fe(III), and Co(II) complexes were fully analyzed by different spectroscopic techniques. The thermal fragmentation of [Cr (HL2)Cl2(H2O)2].10H2O, [Co (HL2)Cl(H2O)2].6H2O, and [Fe(L2)Cl(H2O)2] were analyzed. We have also calculated the thermal parameters with using two different methods. The ligand undergoes tranamidation in the presence of PdCl2. Crystal structure of the product obtained by tranamidation is measured. Biological activities of those compounds were assessed as antioxidants, anticancer, and antimicrobial. [ABSTRACT FROM AUTHOR]

The measurement of Cd (II) ions in various matrices requires the development of sensors that are selective, sensitive, and simple to produce. The cadmium complex of a ligand prepared by the reaction of 2‐pyridinecarbohydrazide with sodium 3‐formyl‐4‐hydroxybenzenesulfonate, [Cd (NaPH)(H2O)].H2O, was synthesized, analyzed by elemental analysis, and structurally elucidated using various spectroscopic techniques. The infrared spectrum of Cd (II) complex suggests a bi‐negative tri‐dentate ONO behavior for the ligand via deprotonated form of both the enolic oxygen atom (C‐O−) and the hydroxyl group of phenolic ring in addition to the azomethine group. The thermal behavior of this complex was revealed using TGA analysis. Applying Coast–Redfern and Horowitz–Metzger equations, we were able to calculate the kinetic and thermodynamic parameters to support the proposed fragmentation experiment for the Cd (II) complex. Cyclic voltammetry measurement was measured to estimate the electrochemical behavior of the Cd (II) ions as well as the impact of adding various NaH2PH ligand concentrations. The biological applications of [Cd (NaPH)(H2O)].H2O complex were assessed as antioxidant, anticancer, and antimicrobial. Based on the Cd (II) complex, we were able to modify Cd (II) ions carbon paste electrode (modified carbon paste electrode, MCPE) as a Cd (II) selective modifier. The created electrode displays a Nernstian slope in the linear range of 0.0001 to 10 mmol/L of 29.16 ± 0.03 mV decade−1, a quick reaction time of 6 s, and pH independence from 3–7. The suggested MCPE demonstrated strong selectivity to Cd (II) ions relative to many other cations and displayed negligible change in the slope or operating range if the experiment was achieved in a partially non‐aqueous solution. This fabricated MCPE was used to determine Cd (II) ions in diverse water samples. [ABSTRACT FROM AUTHOR]

Sodium4‐hydroxy‐3‐([2‐picolinoylhydrazineylidene]methyl)benzenesulfonate (NaH2PH) was synthesized as a novel water‐soluble ligand, by the condensation of picolinohydrazide with sodium 3‐formyl‐4‐hydroxybenzenesulfonate. The (NaH2PH) ligand and its isolated Co (II), Fe (III), Hg (II), and Pd (II) complexes were analyzed by elemental analysis and characterized by spectroscopic (Fourier transform infrared spectroscopy, UV–visible, powder XRD, 1H NMR,13C NMR, MS) and magnetic measurements. By comparing IR spectra of both ligand and the metal complexes, one can assume that the (NaH2PH) ligand behaves as a bi‐negative tetradentate (ONNO) in [Co (NaPH)(H2O)2].3H2O, and a mono‐negative tridentate (ONO) in [Fe (NaPH)Cl2(H2O)] complex, whereas in [Hg2(NaPH)Cl2(H2O)] complex, (NaH2PH) coordinates as a bi‐negative pentadentate (ONNNO) ligand via deprotonated OH group of phenolic ring (C=N)Py and (C=N*) coordinated to one of Hg (II) ion and the oxygen atom of enolic group and (C=N)az group with the another Hg (II) ion. Moreover, (NaH2PH) acts as bi‐negative tridentate (ONO) ligand in [Pd (NaPH)(H2O)].2H2O complex. The geometries of complexes were suggested based on the UV–visible spectra, magnetic measurements and confirmed by applying discrete Fourier transform (DFT) optimization studies. The thermal fragmentation of both [Pd (NaPH)(H2O)].2H2O and [Co (NaPH)(H2O)2].3H2O complexes was performed, and the kinetic and thermodynamic parameters were computed using the Coats–Redfern and Horowitz–Metzger methods. The redox behavior of divalent ions of cobalt and mercury were discussed by the cyclic voltammetry technique in the presence and absence of (NaH2PH) ligand. Biological potencies of the ligand and its metal complexes were evaluated as antioxidants (ABTS and DPPH), anticancer, DNA, and antimicrobial (Staphylococcus aureus and Bacillus subtilis as Gram (+) bacteria, Escherichia coli and Pseudomonas aeruginosa as Gram (−) bacteria, and Candida albicans as fungi). [ABSTRACT FROM AUTHOR]

We report a new high-yield synthesis of so far not accessible tetraphenylphosphonium methylcarbonate Ph4P[OCO2Me] via solvothermal fluoride-induced demethylation and MeF elimination at Me2CO3 (DMC) by Ph4P–F, structurally characterized as λ5-fluorophosphoran by XRD. The synthetic value of Ph4P[OCO2Me] key compound for preparing nearly all kinds of other Ph4P[anion] salts with perfectly crystallizing (not symmetry frustrated) cation is demonstrated by examples beyond ionic liquid research: a complete set of silylchalcogenide salts Ph4P[ESiMe3] (E = S, Se, and Te) including the first example of a structurally characterized non-coordinating, naked [Te–SiMe3]− anion is presented. With this set of soft Lewis bases and metal organic Lewis acids [Cp3La] at hand, a comprehensive series of crystalline 1 : 1 lanthanate complexes Ph4P[Cp3La–ESiMe3] has been prepared. Their structural features and trends such as complexation induced Si–E bond elongation and a pronounced trend in La–E–Si bond angle contraction with E = S < Se < Te are discussed. Heteronuclear 1H, 13C, 29Si, and 139La NMR studies provide a set of 139La NMR shifts for homologs of heavy chalcogen–lanthanum complexes. [ABSTRACT FROM AUTHOR]

In this work, (Z)‐N‐benzoyl‐N′‐(1H‐1,2,4‐triazol‐3‐yl)carbamimidothioic acid and its Mn(II), Co(II), Cu(II) and Cd(II) complexes were introduced for the first time. This carbonyl thiourea ligand was prepared by the reaction of 1H‐1,2,4‐triazol‐3‐amine with benzoyl isothiocyanate. The structural elucidation of these compounds was performed using elemental analysis and spectral and magnetic measurements. Octahedral structures of all complexes, except Cd(II) complex with a tetrahedral geometry, were confirmed by applying DFT structural optimization. The thermal decomposition behaviour of metal complexes of carbonyl thiourea ligand is discussed. The calculation of kinetic parameters for prepared complexes (Ea, A, ΔH*, ΔS* and ΔG*) of all thermal degradation stages has been evaluated using two comparable approaches. Antimicrobial and ABTS‐antioxidant studies indicated potent activity of Cd(II) complex compared with the other investigated compounds. The cytotoxic activity of the prepared compounds was investigated in vitro. The results indicated potent activity of Mn(II) complex against both HePG2 (liver carcinoma) and MCF‐7 (breast carcinoma) cancer cells. [ABSTRACT FROM AUTHOR]

Zn (II), Cd (II), Hg (II) and U (VI)O22+ complexes of water‐soluble thiosemicarbazone ligand (NaH3PyTSC) have been prepared and characterized using various techniques. Fourier transform‐infrared (FT‐IR) demonstrated that NaH3PyTSC ligand behaves as a binegative NOS tridentate in [Hg(H2PyTSC)(H2O)]2 and [UO2(H2PyTSC)(H2O)]2 complexes via the deprotonated SH, (C=N)az groups from one molecule and SO3− group from another molecule, while it behaves as a binegative NNSO tetradentate in [Cd(H2PyTSC)(H2O)2]2 complex through the deprotonated SH group, the SO3− group and the nitrogen of both the (C=N)az and (C=N)py. Finally, it behaves as a binegative OO bidentate in [Zn(H2PyTSC)(H2O)2]2·2H2O complex by the deprotonated OH group from one molecule and SO3− group from another ligand molecule. The spectral data suggest a tetrahedral coordination around Hg (II) and Zn (II) ions, and an octahedral coordination around Cd (II) and U (VI)O22+ ions. The NaH3PyTSC ligand exhibited maximum luminescent intensity at 501 nm, while Zn (II), Cd (II) and Hg (II) chelates show emission bands at 459, 458 and 358 nm, respectively. Two comparable methods were used to estimate various thermodynamic parameters. Cyclic voltammetry has been studied for Cd (II) complex in solution. Different biological applications of the isolated complexes have been estimated. It was found that [Cd(H2PyTSC)(H2O)2]2 showed the most effective antioxidant and anticancer activity. The antioxidant activity of the Schiff base and its complexes. [ABSTRACT FROM AUTHOR]

New carbohydrazone ligand derived from the condensation of carbohydrazide and ethyl acetoacetate, diethyl 3,3′‐(carbonylbis (hydrazin‐2‐yl‐1‐ylidene))(3E,3′E)‐dibutyrate (H4EBC), and its divalent Co, Ni and Cu chelates have been isolated and characterized utilizing convenient methods. 1H‐NMR spectrum of H4EBC revealed the abundance of the enol isomer in solution, which was the opposite to what was shown by the solid IR. This was supported by comparing the theoretical IR of both keto and enol forms. In [Ni(H4EBC)Cl2(H2O)]·2H2O, H4EBC acts as a neutral NON tridentate ligand via the (C=O)carbonyl oxygen atom besides the two (C=N)azomethine nitrogen atoms, while in [Co(H4EBC)Cl2(2H2O)]·2H2O, H4EBC behaves as a neutral NN bidentate ligand through the two azomethine groups. Magnetic measurements inherent to their electronic spectra show that both Ni (II) and Co (II) chelates have octahedron coordination frameworks. On the other hand, the ligand behaves as a binegative tetradentate in [Cu2(H4EBC)Cl2]·H2O via the deprotonated (C=O)carbonyl groups of the ethyl acetoacetate framework and the two (C=N)azomethine groups. In the latter complex, the carbonyl group of the carbohydrazide moiety is converted to hydroxyl group. Cu (II) complex has a tetrahedral geometry according to ESR and electronic spectral data. The reaction of H4EBC with SmCl3·6H2O or LnCl3·7H2O gave single crystals of abnormal product (C16H16N4O4). The packing diagram of this crystal has a chain structure. The photoluminescence spectra of [Cu2(H4EBC)Cl2]·H2O, [Co(H4EBC)Cl2(H2O)2]·2H2O and [Ni(H4EBC)Cl2(H2O)]·2H2O display emission broad‐bands at 342, 321 and 337 nm, respectively. The microbial behavior of the synthesized moieties was investigated against various bacterial and fungal strains. [Cu2(H4EBC)Cl2]·H2O complex shows the same activity as ampicillin towards Escherichia coli and Staphylococcus aureus with inhibition zones of 26 and 22 mm, respectively. Antioxidant activity is determined using bleomycin‐dependent DNA damage assay besides erythrocyte hemolysis. Finally, in vitro cytotoxic activities against two different cell lines have been examined. H‐bonding connecting C16H16N4O4 molecules. [ABSTRACT FROM AUTHOR]

We report a new high-yield synthesis of so far not accessible tetraphenylphosphonium methylcarbonate Ph 4 P[OCO 2 Me] via solvothermal fluoride-induced demethylation and MeF elimination at Me 2 CO 3 (DMC) by Ph 4 P-F, structurally characterized as λ 5 -fluorophosphoran by XRD. The synthetic value of Ph 4 P[OCO 2 Me] key compound for preparing nearly all kinds of other Ph 4 P[anion] salts with perfectly crystallizing (not symmetry frustrated) cation is demonstrated by examples beyond ionic liquid research: a complete set of silylchalcogenide salts Ph 4 P[ESiMe 3 ] (E = S, Se, and Te) including the first example of a structurally characterized non-coordinating, naked [Te-SiMe 3 ] - anion is presented. With this set of soft Lewis bases and metal organic Lewis acids [Cp 3 La] at hand, a comprehensive series of crystalline 1 : 1 lanthanate complexes Ph 4 P[Cp 3 La-ESiMe 3 ] has been prepared. Their structural features and trends such as complexation induced Si-E bond elongation and a pronounced trend in La-E-Si bond angle contraction with E = S < Se < Te are discussed. Heteronuclear 1 H, 13 C, 29 Si, and 139 La NMR studies provide a set of 139 La NMR shifts for homologs of heavy chalcogen-lanthanum complexes.