Molar Conductance Measurements Research Articles

Synthesis, Structural Studies and Antimicrobial Evaluation of Nickel(II) Bis-Complex of Schiff Base of S-Benzyldithiocarbazate

A tridentate nitrogen-oxygen-sulfur (NOS) S-benzyl(2-oxoindolin-3-ylidene)dithiocarbazate, HSBISA (HL1) ligand was synthesized via a condensation reaction between S-benzylditihocarbazate (SBDTC) and isatin. The produced ligand was reacted with nickel(II) acetate salt in 1:2 (metal:ligand) ratio to yield a brown Ni(SBISA)2 complex (2) (SBISA = monoanionic form of HL1). Characterization of HL1 and its Ni(II) complex was performed via elemental analysis, FT-IR, ICP-AES, UV-Vis spectroscopy and mass spectrometry, along with molar conductivity and magnetic susceptibility measurement. Slow evaporation of 2 from DMSO at room temperature led to a structure crystallizing in the monoclinic P21/a space group with a = 18.6860(3), b = 11.3037(2), c = 19.8993(3), b = 112.1897(10), V = 3891.86(11) Å3, wR2 (all data) = 0.0407 and R1 = 0.0386 for data with I > 2σ(I). The nickel(II) metal center is ligated by doubly-deprotonated NOS monoanionic tridentate HL1 ligands forming a neural distorted octahedral Ni(SBISA)2×2DMSO (2a) complex. The antimicrobial assays of both compounds were performed on selected pathogenic bacteria and fungi strains. HIGHLIGHTS Octahedral Ni(II) complex was synthesized using acetate salt Compound was characterized via physico-chemical analyses Structural studies were resolved via single crystal X-ray diffraction Compound 2a crystallized in a monoclinic system (P21/a space group) with cell parameters a = 18.6860 (3), b = 11.3037 (2), c = 19.8993(3), b = 112.1897 (10), V = 3891.86 (11) Å3, wR2 (all data) = 0.0407 and R1 = 0.0386 for data with I > 2σ(I) Compound was evaluated for its antimicrobial activity GRAPHICAL ABSTRACT

Ancillary-Ligand-Assisted Variation in Nuclearities Leading to the Formation of Di-, Tri-, and Tetranuclear Copper(II) Complexes with Multifaceted Carboxylate Coordination Chemistry

The self-assembly of a carboxylate-based dinucleating ligand, N,N'-bis[2-carboxybenzomethyl]-N,N'-bis[2-pyridylmethyl]-1,3-diaminopropan-2-ol (H3cpdp), and copper(II) ions in the presence of various exogenous ancillary ligands results in the formation of the new dinuclear complex [Cu2(cpdp)(μ-Hisophth)]4·2H2isophth·21H2O (1), trinuclear complex [Cu3(Hcpdp)(Cl)4] (2), and tetranuclear complex [Cu4(cpdp)(μ-Hphth)(μ4-phth)(piconol)(Cl)2]·3H2O (3) (H2phth = phthalic acid; H2isophth = isophthalic acid; piconol = 2-pyridinemethanol; Cl- = chloride). In methanol-water, the reaction of H3cpdp with CuCl2·2H2O at room temperature leads to the formation of 2. On the other hand, 1 and 3 have been obtained by carrying out the reaction of H3cpdp with CuCl2·2H2O/m-C6H4(CO2Na)2 and CuCl2·2H2O/o-C6H4(CO2Na)2/piconol, respectively, in methanol-water in the presence of NaOH at ambient temperature. All three complexes have been characterized by elemental analysis, molar electrical conductivity and magnetic moment measurements, FTIR, UV-vis spectroscopy, and PXRD, including single-crystal X-ray structural analyses. The molecular structure of 1 is based on a μ-alkoxide and μ-isophthalate-bridged dimeric [Cu2] core; the structure of 2 represents a trimeric [Cu3] core in which a μ-alcohol-bridged dinuclear [Cu2] unit is exclusively coupled with a [CuCl2] species by two μ:η1:η1-syn-anti carboxylate groups forming a triangular motif; the structure of 3 embodies a tetrameric [Cu4] core, with two copper(II) ions in a distorted-octahedral coordination environment, one copper(II) ion in a distorted-trigonal-bipyramidal coordination environment, and the other copper(II) ion in a square-planar coordination environment. In fact, 2 and 3 represent rare examples of copper(II)-based multinuclear complexes showing outstanding features of rich coordination chemistry: (i) using a symmetrical dinucleating ligand, trinuclear complex 2 is generated with four- and five-coordination environments around copper(II) ions; (ii) the unsymmetrical tetranuclear complex 3 is obtained by using the same ligand with four-, five- and six-coordination environments around copper(II) ions; (iii) tetracopper(II) complex 3 shows four different bridging modes of carboxylate groups simultaneously such as μ:η2, μ:η1:η1, μ3:η2:η1:η1, and μ4:η1:η1:η1:η1, the μ4:η1:η1:η1:η1 mode of phthalate being unprecedented. The formation of these [Cu2], [Cu3], and [Cu4] complexes can be controlled by changing the exogenous ancillary ligands and pH of the reaction solutions, thus allowing an effective tuning of the self-assembly. The magnetic susceptibility measurements suggest that the copper centers in all three complexes are antiferromagnetically coupled. The thermal properties of 1-3 have been investigated by thermogravimetric and differential thermal analytical (TGA and DTA) techniques, indicating that the decomposition of all three complexes proceeds via multistep processes.

Synthesis, characterization and antimicrobial properties of Cobalt(III), Nickel(III), Copper(II) and Zinc(II) complexes with pyridine and thiocyanate

Mixed-ligand complexes of Co(III), Ni(III), Cu(II) and Zn(II) with pyridine and thiocyanate have been synthesized and characterized using elemental analysis, infrared and UV-Vis spectroscopy, thermal analytical techniques, melting point determination, molar conductivity and room temperature magnetic susceptibility measurements. The results suggest that all complexes are stable and molecular with octahedral coordination geometry for the Co(III) and Ni(III) complexes, square planar or tetrahedral geometry for the Cu(II) complex and a tetrahedral geometry for the Zn(II) complex. Evaluation of the antimicrobial activities of the ligands, metals salts and complexes on four bacterial strains (E. Coli, K.Pneumonia, S.typhi and S. flexneri) and four fungal strains (C. Albicans, C., Parapsilopsis, C. tropicalis and C. neoformans) showed higher activity of the complexes compared to the ligands and metals salts. The Co(III) complex showed higher activity than the reference drugs; doxycycline and Penicillin while the Cu(II) complex showed higher activity than the reference antibiotics; doxycycline and nystatin.

Ligational behavior of a new bis (bidentate NO) donor hydrazone towards Co (II), Ni (II), and Cu (II) ions: Preparation, spectral, thermal, biological, docking, and theoretical studies

Reaction of 4,6‐bis(1‐hydrazonoethyl)benzene‐1,3‐diol with 3‐nitrobenzaldehyde gave the new bis (bidentate) hydrazone ligand; 4,6‐bis(3‐nitrobenzalen‐1‐yl)methylene)hydrazono)ethyl)benzene‐1,3‐diol (H2L; H2BisBD). Binuclear Co (II), Ni (II), and Cu (II) complexes of general formula ([M2BisBD(H2O)x (EtOH)y].nH2O; M = Co, Ni or Cu, x = 4 or 6, y = 2 or 0; n = 1 or 0) have been successfully prepared. The structures of H2BisBD and its complexes have been characterized by means of analytical, spectroscopic (infrared, proton nuclear magnetic resonance, mass, UV–Vis, and electron spin resonance), molar conductivity, and magnetic susceptibility measurements and thermal gravimetric analysis. Octahedral geometrical structures were proposed for all complexes in which the hydrazone ligand behaves as a bis (monoanionic bidentate) via azomethine nitrogen and phenolic oxygen donor atoms. The scanning electron microscopy refers that the copper (II) complex is in the nano scale. The ligand and its complexes showed antitumor activity against Hepatocellular carcinoma. Complexation process improved the antitumor activity, and copper (II) complex showed a promising activity, which agree with docking data. Theoretical studies for the prepared compounds were calculated using Hyperchem program at PM3.

Synthesis and characterization of Phenyl bis- hydrazone complexes with Pd (II), Mn (II), Ni (II) and Fe(III) ions

A new ligand of phenyl bis-hydrazone (V) was been synthesized as a result of a reaction between phenyl-isatin hydrazone and salicyladehyde. The yellow crystals of (V) was been studied using IR, 1H.n.m.r 13C-n.m.r, UV-Vis spectrum and molar conductivity measurements. The complexes of Palladium (II), Nickel (II), Manganese (II) and Iron (III) with phenyl bis-hydrazone have been synthesized and characterized on based on molar conductivity, magnetic susceptibility data, UV-Vis and IR spectral studies. The spectral data referred to that the ligand acts as monobasis tridentate, coordinating through phenolate oxygen, azomethine nitrogen, and carbonyl oxygen of isatin moiety. On the basis on the above results an octahedral geometry has been proposed for the mentioned complexes.

Synthesis and Characterization of Some Metal Complexes Derived from Azo Ligand of 4,4' Methylenedianiline and Resorcinol

The metal complexes of Azo dye; 4,4'-((methylene bis(3,l-phenylen)) bis (diazene-l,2-diyl)) bis(1,3-Benzenediol) are produced from 4,4`- methylenedianiline and Resorcinol were synthesized and characterized by using several analytical and spectral techniques. The ligand and its complexes were characterized by many chemo-physic methods like NMR, IR, UV-Vis, molar conductance measurement, analytical measurement, and melting point. The conditions of optimal reaction (for instance reagent concentration, pH etc) were studied and the analytical figures of merit such as limit of detection, linearity, sensitivity etc) were obtained.

Synthesis and Biological Evaluation, Structural Elucidation, Thermogravimetric Analysis, X-Ray Diffraction Studies of a Schiff Base Derived from 3-formylchromone and 3-aminoquinoline and their Cu(II) and Co(II) Complexes

Introduction: The study of novel Schiff bases and their metal complexes has achieved enormous attention of inorganic as well as medicinal chemists. Objective: The objective of this study is to study the structural elucidation and antimicrobial screening of 3-formylchromone and 3-aminoquinoline-based Schiff base and their metal complexes. Methods: Cu(II) and Co(II) complexes of 3-((quinolino-3-ylimino) methyl)-4H-chromen-4- one ligand were synthesized and characterized by elemental analysis, molar conductivity measurement, infrared, UV-Visible, 1H NMR spectral studies, thermogravimetric analysis, and powder X-ray diffraction studies. Results: Antibacterial activity of synthesized compounds were screened against Klebsiella pneumoniae, Staphylococcus aureus, and Proteus vulgaris, and antifungal activity was screened against fungi Candida albicans and Aspergillus niger. Schiff base ligand and their Cu(II) and Co(II) complexes revealed significant antibacterial and antifungal activity against tested strains. Octahedral geometry of metal complexes was proven by analytical, physical, and spectral data. Conclusion: In this present work, novel Schiff base 3-((quinolino-3-ylimino) methyl)-4Hchromen- 4-one and its Cu(II) and Co(II) complexes revealed promising antibacterial and antifungal activities.

Zinc(II) complexes bearing N,N,S ligands: Synthesis, crystal structure, spectroscopic analysis, molecular docking and biological investigations about its antifungal activity

In the present work, the synthesis, characterization, antifungal activity, molecular docking study and in silico approach of five thiosemicarbazone derivatives and their corresponding zinc(II) complexes are described. The compounds were characterized by elemental analysis, IR, UV–Vis and NMR spectroscopic measurements, molar conductivity measurements, emission spectra, high-resolution mass spectrometry and X ray study. The antifungal activity of the free ligands and synthesized compounds was preliminarily evaluated against Candida albicans (ATCC 90028), Candida tropicalis (ATCC 13803) and Candida glabrata (ATCC 2001), by the minimum inhibitory concentration (MIC) assay. Two complexes, 4 (MIC = 3.18 to 6.37 μM) and 5 (MIC = 25.95 μM for all) showed promising results, being highly active against all strains evaluated. The X-ray analyses shown that the complex 2 crystallizes in the centrosymmetric space group P21/c of the monoclinic system and the coordination sphere around zinc(II) atom is better described as slightly distorted octahedral. The Hirshfeld surface (HS) analysis showed that non-classical H···H and C···H/H···C contacts contribute with 65.9% while the S···H and N···H (21%) and Cl···H and O···H interactions (12%) complete the HS area. The molecular docking results, performed against CYP51 enzyme (sterol 14α-demethylase) of C. albicans and C. glabrata shows that the complexes 4 (ΔG = −10.75 and − 12.90 kcal/ mol) and 5 (ΔG = −11.12 and − 14.53 kcal/ mol) showed the highest binding free energies of all compounds. The ADME-Tox (absorption, distribution, metabolism, excretion and toxicity) in silico parameters evaluated showed promising results for all compounds.

Synthesis, spectral investigation, biological activities and docking stimulation of novel metal complexes of Trifluoro phenylthiazol derivative with computational studies

In this investigation, we prepared the new ligand (HL) of 1,1,1-trifluoro-4-((4-phenylthiazol-2-yl)imino)pent-2-en-2-ol(3), which was obtained from the condensation of 1,1,1-trifluoroacetylacetone(1) with 2-amino-4-Phenylthiazole(2). HL ligand was then reacted with the nitrate salts of Cr(III), Fe(III), Co(II), Ni(II), Cu(II), and Zn(II) to afford the novel metal complexes. The chemical structures were validated through elemental analysis, UV-Visible, IR, ESR, 1H NMR, mass spectra, TGA, magnetic, and molar conductance measurements. The enolic oxygen and azomethine nitrogen were involved in the bidentate binding of the HL ligand and the theoretical studies, utilizing DFT/LANL2DZ, confirmed the binding modes and the stability of the complexes. The thermal stability of all complexes was determined using TGA analysis, and the kinetic parameters were obtained using the Coats-Redfern method. Additionally, the synthesized HL and its metal complexes exhibited antimicrobial activities against Gram-positive, Gram-negative, and fungi strains. These findings were confirmed using molecular docking with a variety of proteins such as PDBID: 3t88, PDBID: 1tgh, PDBID: 2wje and PDBID: 4ynt with least binding energy and different bond lengths. In addition, the synthesized complexes showed excellent in vitro-antitumor activities contra human colon cancer cells HCT-116 which is comparable to the African green monkey kidney's normal cells and showed the selectivity index (S.I.) of Cu(II) and Zn(II) complexes was determined to be 62.46 and 66.70; respectively, indicating superior activity of these complexes compared to methotrexate as a reference compound with a value of S.I. = 20.64., and also this result was confirmed the stability of the complex with PDBID: 2x7fand PDBID: 3x0G through molecular docking studies. Moreover, HL and all metal complexes showed stability when optimized through the DFT/LANL2DZ basis set and also their physical descriptors and HOMO-LUMO, MEP and ESP were determined.

SYNTHESIS, SPECTROSCOPIC, THERMAL AND BIOLOGICAL STUDIES of SOME NOVEL METAL IONS COMPLEXES

In the current study, a novel heterocyclic azo ligand, 4-[6-(p-phenyl phenol)azo] cytosine(PAC), is synthesized through a general diazo coupling reaction with lanthanide ions [La(III), Nd(III), and Eu(III)]. The molecular formulae of the newly synthesized compounds were established using a variety of spectroscopic methods, including [FT-IR, UV-Vis, and HNMR], elemental analysis (C.H.N), thermal gravimetric analysis (TGA), magnetic measurement, molar conductivity measurement, stability constant, and Gibbs free energy. Using the mole ratio method, the complexes stoichiometry was determined using data from spectroscopic analyses of the complexes' solutions for the chosen ions. The metal to ligand mole ratio, however, was (1:2). When the biological effectiveness of each compound was tested against various bacteria and fungi strains, the results showed good activity when compared to the standard medication. additionally possess effective cancer prevention and dyeing performance

Hidrazon Türevi Yeni Fe(II), Co(II), Ni(II) ve Cu(II) Komplekslerinin Sentezi ve Karakterizasyonu

2-hidroksinaftaldehit ile nikotinik hidrazit'in kondenzasyon reaksiyonundan N-((2-hidroksinaftalen-1-il)metilen)nikotinohidrazit ligandı elde edilmiştir. N-((2-hidroksinaftalen-1-il)metilen)nikotinohidrazit ligandı ile Fe(II), Co(II), Ni(II) ve Cu(II) asetat tuzlarının (2:1) reaksiyonundan yeni hidrazon metal L2Fe, L2Ni, L2Co ve L2Cu2 kompleksleri sentezlenmiştir. Sentezlenen bileşikler FT-IR, NMR (sadece ligand), UV-Vis, elementel analiz, molar iletkenlik ölçümü, manyetik duyarlılık gibi tekniklerle karakterize edilmiştir. Manyetik duyarlılık ölçümleri L2Fe, L2Co L2Ni ve L2Cu2 kompleksleri için sırasıyla 5.96 BM, 1.03 BM, 1.08 BM ve 1.61 BM olarak kaydedilmiştir. L2Cu2, L2Ni ve L2Co komplekslerinin antiferromanyetik özellikte olduğu belirlenmiştir. L2Fe, L2Co ve L2Ni kompleksleri oktahedral, L2Cu2 kompleksi ise kare düzlem geometriye sahiptir. Komplekslerin molar iletkenlik değerleri 1.31-2.61 μS/cm arasında olup, iletkenlik özelliği taşımamaktadır.

Novel NO2 semicarbazone ligand and its metal complexes as VEGFR‐2 inhibitors: Synthesis, spectral characterization, density functional theory calculations, molecular docking, and antimicrobial and antitumor evaluation

A novel semicarbazone NO2 ligand, H2L, was synthesized. The ligand reacted with several metal ions such as Cu(II), Ni(II), Co(II), Fe(III), Cr(III), and Mn(II) in a molar ratio 1:1 (M:L). The H2L ligand and its metal complexes were characterized by electronic, infrared, mass, nuclear magnetic resonance, electron spin resonance spectra, as well as elemental analysis, thermal analysis, molar conductance, and magnetic susceptibility measurements. The Coats–Redfern equations were used to calculate the kinetic parameters (Ea, A, ΔH, ΔS, and ΔG) of the thermal decomposition stages. The H2L ligand acts as dianionic NO2 tridentate in all complexes and coordinates through enolate oxygen, azomethine nitrogen, and deprotonated OH group. The geometrical arrangements in all metal complexes were octahedral geometries. Based on density functional theory (DFT) level implemented in the Gaussian 09 program at B3LYP/6‐311G(d,p) level, the molecular structural parameters of the ligand and its metal complexes were calculated, and the theoretical data were connected with the experimental results. The antimicrobial activity of the current compounds was examined against Gram‐positive bacteria (Staphylococcus aureus and Bacillus subtilis), Gram‐negative bacteria (Salmonella typhimurium and Escherichia coli), yeast (Candida albicans), and fungus (Aspergillus fumigatus). The antitumor activity of the ligand and its metal complexes was investigated against HepG2 cell line, which revealed promising IC50 values comparable with that of Cis‐platin. All synthesized compounds were also subjected to molecular docking studies to investigate their binding pattern and affinity for the VEGFR‐2 active site and correlated with antitumor data.

Characterization Studies on Mn(II), Co(II), Ni(II), Cu(II), Zn(II) and Cd(II) Complexes with New Ligands Derived from Anthraquinone Substance

This work involves preparation of new metal complexes via reaction of two anthraquinone ligands with Mn(II), Co(II), Ni(II), Cu(II), Zn(II) and Cd(II) metal ions . The ligands are prepared by treatment of 1- and 2-anthraquinone with acetic anhydride. The complexes are characterized by different physicochemical methods; microelemental analysis, molar conductivity, FT-IR, UV-Vis spectra and magnetic measurements. The discussion of the outcome data of the prepared complexes indicates that all complexes are octahedral. The biological activity properties of the ligands and most of their complexes are studied using gram-positive and gram-negative bacteria, which indicate that only two of the complexes show biological activity.

Spectroscopic and Molecular Docking Studies of Cu(II), Ni(II), Co(II), and Mn(II) Complexes with Anticonvulsant Therapeutic Agent Gabapentin.

New Cu(II), Ni(II), Co(II), and Mn(II) complexes of the gabapentin (Gpn) bidentate drug ligand were synthesized and studied using elemental analyses, melting temperatures, molar conductivity, UV–Vis, magnetic measurements, FTIR, and surface morphology (scanning (SEM) and transmission (TEM) electron microscopes).The gabapentin ligand was shown to form monobasic metal:ligand (1:1) stoichiometry complexes with the metal ions Cu(II), Ni(II), Co(II), and Mn(II). Molar conductance measurements in dimethyl-sulfoxide solvent with a concentration of 10−3 M correlated to a non-electrolytic character for all of the produced complexes. A deformed octahedral environment was proposed for all metal complexes. Through the nitrogen atom of the –NH2 group and the oxygen atom of the carboxylate group, the Gpn drug chelated as a bidentate ligand toward the Mn2+, Co2+, Ni2+, and Cu2+ metal ions. This coordination behavior was validated by spectroscopic, magnetic, and electronic spectra using the formulas of the [M(Gpn)(H2O)3(Cl)]·nH2O complexes (where n = 2–6).Transmission electron microscopy was used to examine the nanostructure of the produced gabapentin complexes. Molecular docking was utilized to investigate the comparative interaction between the Gpn drug and its four metal [Cu(II), Ni(II), Co(II), and Mn(II)] complexes as ligands using serotonin (6BQH) and dopamine (6CM4) receptors. AutoDock Vina results were further refined through molecular dynamics simulation, and molecular processes for receptor–ligand interactions were also studied. The B3LYP level of theory and LanL2DZ basis set was used for DFT (density functional theory) studies. The optimized geometries, along with the MEP map and HOMO → LUMO of the metal complexes, were studied.

Isophthaloylbis (Azanediyl) Dipeptide Ligand and Its Complexes: Structural Study, Spectroscopic, Molecular Orbital, Molecular Docking, and Biological Activity Properties

The ligand 2,2′-(isophthaloylbis(azanediyl))bis(3-phenylpropanoic acid; H2L) was used to build novel metal complexes of Co(II), Ni(II), Fe(III), and Zn(II) metal ions. Elemental analyses, thermal, infrared, mass, electronic spectra, magnetic moments, X-ray diffraction analysis, and conductivity measurements were used to predict the nature of bonding and the stereochemistry of the complexes. The complexes were proposed to have the general formula [M(H2L)(H2O)2]Cl n , where M = Co(II), Ni(II), and Zn(II) (n = 2) and Fe(III) (n = 3), based on the elemental analyses data. All of the complexes were electrolytes, according to the molar conductivity measurements. The FT-IR spectra revealed that the dipeptide ligand is tetradentately coordinated to metal ions, with NNOO donor atoms participating in coordination with metal (II)/(III) ions, resulting in octahedral complexes. Using the recommended programme, the structural formula for the investigated ligand was optimized. Using the density-functional theory (DFT) approach, the energy gaps and other essential theoretical parameters were calculated. The agar diffusion method was used to test the in vitro biological characteristics of the ligand (H2L) and its transition metal complexes against Gram(+) bacteria (Bacillis subtilis and Staphylococcus aureus) and Gram(−) bacteria (Escherichia coli and Pseudomonas aeruginosa). The title compounds were found to be more biologically active than the parent dipeptide ligand. The title compounds have a good interaction with the crystal structures of 3t88-Escherichia coli, 3ty7-S. aureus, 5h67-Bacillus subtilis, and 5i39-Pseudomonasaeruginosa, according to molecular docking study.

New Homo and Heterobinuclear Macrocyclic Complexes Bearing Isatine Structural Characterization, Thermal Study and DFT Calculations

A new metal-free macrocyclic Schiff base ligand bearing two metal cavities incorporated with two sets of N3O2 donor atoms derived from 2, 6-diaminopyridine and isatine was synthesized. The new ligand was used to prepare homo and hetero binuclear macrocyclic Schiff base complexes with Ni (II), Cu (II), ZrO (II) and Ba (II) metal ions. The ligand and metal complexes were characterized using Fourier transform infrared (FT-IR), UV–vis, mass spectroscopy, elemental analysis (CHN), thermo gravimetric analysis (TGA), magnetic susceptibility, and molar conductivity measurements. The DFT calculations using the B3LYP functional method have been applied to obtain the geometry and electronic properties of the ligand and its metal complexes to support the experimental data. To describe the reactivity of the title molecules, the HOMO and LUMO levels and Mulliken atomic charges were determined.

Synthesis, characterization, in-silico, and in-vitro biological studies of Cu(II), Zn(II) complexes of semicarbazone, thiosemicarbazone derivatives of dehydrozingerone

Treatment of multidrug resistance pathogens has been a challenge for several decades. Herein, we report a novel Cu(II) and Zn(II) complexes of dehydrozingerone derivatives of semicarbazone and thiosemicarbazone. The semicarbazone and thiosemicarbazone derivative ligands were prepared by a modified method with better yield using aldol condensation. The prepared ligands and their metal complexes were characterized with spectroscopic methods (UV, IR, 1H-NMR, 13C-NMR, and DEPT-135), molar conductivity measurements, and thermogravimetric analysis (TGA). The compounds were assessed for antibacterial and antioxidant potential by following the disk diffusion and DPPH methods, respectively. The antimicrobial assay results show that ligands (L1 & L2) show lower to medium mean inhibition zones from 3.5 ± 0.00 -10.86 ± 0.82 mm at 100 µg/mL and 200 µg/mL. The complexes exhibited better antibacterial potential (7.44 ± 0.55 -15.44 ± 0.31 mm) as compared to ligands alone. Also, the complexes exhibited better percent antioxidant potential than both ligands. Furthermore, in silico docking data of compounds on Staphylococcus aureus gyrase confirms the prepared compounds are potential molecules with minimum interaction energy from – 7.6 to – 9.1 kcal/mol. The highest result was achieved by [Zn(L1)2(H2O)2] complex (– 9.1 kcal/mol). Therefore, the structural modification of dehydrozingerone to semicarbazone and thiosemicarbazone derivatives, and subsequent complexation with metals can enhance biological potentials.

Synthesis, Characterization, Antioxidant and Antibacterial Studies for New Schiff Base Complexes derived from 4-Bromo-O-toluidine

In this article, new Schiff base ligand LH-prepared Mn(II), Co(II), Ni(II), Cu(II), Zn(II), Cd(II), Hg(II), Pd(II), and Pt(II) materials were analyzed using spectroscopy (1 Metal: 2 LH). The ligand was identified using techniques such as FTIR, UV-vis, 1H-13C-NMR, and mass spectra, and their complexes were identified using CHN microanalysis, UV-vis and FTIR spectral studies, atomic absorption, chloride content, molar conductivity measurements, and magnetic susceptibility. According to the measurements, the ligand was bound to the divalent metal ions as a bidentate through oxygen and nitrogen atoms. The complexes that were created had microbicide activity against two different bacterial species and one type of fungus. DPPH techniques were being used to test the ligand and its complexes for antioxidant activity.

Potency of copper(II) complexes towards drug-sensitive and -resistant Plasmodium falciparum: Structure-activity relationship, ROS-generation and proteasome inhibition

The use of copper in medicine has a long history and copper-containing compounds have multiple applications, such as in treating heart disease, arthritis, cancer, parasitic as well as other inflammatory diseases. Here, we investigate structural factors, structure-activity relationship and two mechanisms of action of a series of copper(II) complexes with 1,10-phenanthroline (phen) and/or amino acid ligands towards Plasmodium falciparum (Pf) 3D7 and artemisinin-resistant Pf5202. To achieve this, the following set of copper(II) complexes, viz. [Cu(phen)Cl2] 1, [Cu(phen)2Cl]Cl·2H2O 2, [Cu(phen)(gly)Cl]·2H2O 3, [Cu(phen)(edda)]·5H2O 4, cis-[Cu(gly)2(H2O)] 5 and [Cu(edda)] 6, (gly = glycine; edda = ethylenediamine-N,N’-diacetic acid) were selected, synthesized and characterized by FTIR, elemental analysis, UV-Visible spectroscopy, molar conductivity measurement and magnetic moment. Herein, we report comparison of aqueous copper(II) species, CuCl2 and ligands in inhibiting proteolytic sites of 20S proteasome, generation of reactive oxygen species, hemolysis and antimalarial property. Factors affecting their antimalarial potency are different from those affecting proteasome inhibition and ROS production. Complexes 1 – 4, with IC50 values of about 3 µM towards Pf3D7, were more effective against artemisinin-resistant strain Pf5202 than chloroquine and artemisinin. Evidence of apoptosis of malaria parasite in red blood cells is also presented.

Synthesis , Antibacterial Activity of Sm(III) Complex With L-phenylalanine

Synthesis , Antibacterial Activity of Sm(III) Complex With L-phenylalanine