Electronic Spectral Studies Research Articles

Salicylaldehyde salicyloyl hydrazone and its copper(II) complex: synthesis, characterization, DFT, optical band gap, antibacterial activity, and molecular docking analysis

A complex of Cu(II) with a bidentate Schiff base, salicylaldehyde salicyloyl hydrazone (SSH), was synthesized by refluxing copper(II) chloride with this ligand. The formation of the complex, the nature of bonding, and the geometry of the complex were established via physicochemical and spectroscopic techniques. The composition of the complex was found to be a 1:2 metal-ligand ratio as Cu(SSH)2. Electronic absorption spectral studies revealed that the copper adopts a distorted tetrahedral geometry upon complexation with SSH. The optical band energy for the complex was determined from absorption spectroscopy. The obtained band gap of 2.66 eV characterizes the complex as a semiconductor. The most stable conformations of the Schiff base (SSH) and Cu(SSH)2 complex have been computed, shedding light on their structural and electronic properties, and highlighting their potential reactivity and stability. The ligand exhibits a higher reactivity towards electrophiles, while the complex displays a greater affinity for nucleophiles. The in vitro antibacterial analysis with agar cup well method and in silico molecular docking analysis indicate that both the ligand and its complex with copper have potency to inhibit bacterial infections. Based on their growth inhibition, minimum inhibitory concentration (MIC) values, and robust interaction with studied proteins of the pathogens, these compounds hold a prospective avenue for the advancement of antibiotics.

Synthesis, Spectroscopic, Computational, and Biological Evaluation of Pyrazole mono azo dyes

In the present work, a series of new dispersed mono azo dyes (3) were synthesized through conventional diazo-coupling reaction between 4-hydroxy-phenylacetamide with pyrazole derivatives at low temperature. All the synthesized mono azo compounds were characterized by various spectroscopic methods like IR, NMR, electronic spectral, LC-MS, and fluorescence spectral studies. The experimental IR data was compared with that of the theoretical data and it has been observed that, the experimental IR spectral values are found to be lower than that of the theoretical values. The quantum chemical calculations were also carried out to understand the chemical reactivity of the compounds by using B3LYP method in conjugation with 6-311++G (d, p) basis set. The compounds were screened for anti-tuberculosis properties against M. tuberculosis and the compound 7 was found to exhibit a significant inhibitory effect with MIC value of 12.5μg/mL. The anti-microbial studies were carried for synthesized mono azo compounds. Further, the in silico molecular docking study was carried out to know the significant interaction of the synthesized compounds against VEGFR2 target protein.

Chitosan polymers randomly labeled with pyrene: synthesis, photophysics, and selective quenching by metal cations and anions

The synthesis together with a comprehensive electronic spectral and photophysical study of two chitosan polymers randomly labeled with different degrees of pyrene were here undertaken. The polymers, denoted as ChiNPy-A and ChiNPy-B, have different degrees of substitution with pyrene (%DSPy), with values of 0.5 and 4.5, respectively. The resulting polymers consist in four distinct units, including the deacetylated and acetylated units and the grafted imine and amine pyrene units, obtained by a Schiff base formation reaction and subsequent reduction, respectively. Time-resolved fluorescence measurements in aqueous solution revealed triple exponential decay fits that characterizes the fluorescence properties of the amine- and imine-pyrene-linked units, as well as self-quenching of pyrene units. The ChiNPy polymer showed fluorescence quenching of its pyrene amine units, with lead (II) and mercury (II) exhibiting the highest degree of fluorescence quenching. From Stern-Volmer type plots, two distinct populations of fluorophores were observed. These findings emphasize the potential of chitosan pyrene-labeled polymers as sensitive fluorescent probes, particularly for detecting metal cations.

One-pot domino synthesis of 1,2,4-triazolo [3,4-b][1,3,4] 6-amino thiadiazines and their CT-DNA binding study

A facile one-pot three component domino protocol has been successfully developed for the combinatorial synthesis of novel Schiff bases of 3-(2-(6-amino-7H- [1,2,4]-triazolo[3,4-b] [1,3,4]thiadiazin-3-yl)hydrazineylidene)indolin-2-ones 4, 5. This protocol utilizes readily available starting materials, leads to produce high yields (79–92 %).This domino reaction involves the formation of three new bonds (two CN and one C–S bond) and one heterocyclic ring in a single step. Notably, this reaction shows several remarkable features, such as short reaction time, eliminating the requirement for extensive workup and column chromatographic purification. In addition to this, the reaction demonstrates good scalability, producing satisfactory yields even on a gram -scale. Further, all the compounds were screened for their electronic absorption and fluorescence emission spectral studies by using CT-DNA. Compounds 5l, 5m, 5r, 5o, 5s have shown greater binding affinity with CT-DNA. In fluorescence emission spectra 5l, 5o, 5s demonstrate good quenching constant values with CT-DNA. And also, molecular docking studies were carried out for all the synthesized compounds.

Synthesis, Characterization, Biological Properties, ADMET and Drug-likeness Analysis of Mn (II) complexes with Schiff Bases Derived from Sulphathiazole and 4-diethylaminosalicyaldehyde/Salicyaldehyde

Mn (II) complexes were synthesized with the Schiff base ligand obtained by the condensation of sulfathiazole with 4-diethylaminosalicyaldehyde/Salicyaldehyde. Their characterization was performed by elemental analysis, molar conductance, melting points, magnetic susceptibility, infrared, and UV–Vis spectral analysis. The results suggest that the Schiff bases and their complex are synthesized in excellent yield, molar conductance studies on the complexes indicated they were non-electrolytic. The IR data indicated that the Schiff base ligand is tridentate coordinated to the metallic ion with two N atoms from the azomethine group and thiazole ring and one O atom from the phenolic group. The electronic spectral study showed octahedral geometry for all the complexes which are further supported by magnetic moment values. The ligand and its complexes were screened against four bacterial and two fungal strains using the disk diffusion method. The antimicrobial evaluation results revealed that the metal (II) complexes exhibited higher antimicrobial activity than the free Schiff base ligand. The ADMET and drug-likeness studies of the synthesized ligands indicated that the Schiff base ligands fulfill Lipinski’s, Ghoose, Veber, Egan, and Mugge rules but the complexes showed some deviations. They also displayed low toxicity levels.

Trivalent Metal Complexes of Rich-Hyrdoxy Schiff base Ligand: Synthesis, Characterization, DFT Calculations and Antimicrobial Activity

The design of trivalent metal complexes involves choosing suitable ligands that can bind to the metal and confer the desired properties. In this study, novel trivalent metal complexes (TVMCs) of Ru, Fe, and Cr were synthesized from a newly developed hydroxy-rich Schiff base ligand (LH2) derived from 4,4'-oxydianiline with 2, 4-dihydroxybenzaldehyde, which is referred to as N, N`-bis [ 2,4-dihydroxyphenyl-methylidene] 4,4'-oxydianiline (LH2). The ligand synthesis was performed using reflux without a catalyst in ethanol. The products underwent thorough characterization experimentally by various techniques such as: FT-IR, 1H-NMR, 13C-NMR, Powder XRD, elemental analysis, UV-Visible, conductivity, magnetic susceptibility, and thermal gravimetric analysis. The molar conductance measurements suggest that the complexes are non-electrolytes and do not contain conductive species outside the coordination sphere. Thus they can be formulated as [MLCl(H2O)].nH2O. Magnetic moment and electronic spectral studies confirmed that all complexes exhibit octahedral geometry around the metal ion. Furthermore, density functional theory (DFT) calculations were performed theoretically to investigate the structures, frontier molecular orbitals (HOMO and LUMO), molecular electrostatic potential (MEP), and electron localization function (ELF) for all complexes, utilizing the Gaussian09 software and the B3LYP/6-311+G(d, p) level. In vitro experiments were conducted to evaluate the antibacterial activity of the compounds against both Gram-negative (Escherichia coli) and Gram-positive (Staphylococcus aureus) bacterial species, using the agar diffusion method. The results indicate that the Fe(III)-complex exhibits noteworthy inhibitory effects on both Gram-positive and Gram-negative bacteria, with a maximum inhibition zone.

Experimental and theoretical studies on structural aspects of transition metal complexes of isonicotinoyl N‐oxide hydrazone: Their DNA‐binding interaction and cytotoxicity

Equilibrium studies of isonicotinoyl N‐oxide hydrazone [4‐(2‐(4‐(diethylamino)‐2‐hydroxybenzylidene) hydrazine carbonyl) pyridine1‐oxide] were carried out by employing pH‐metric titrations in 40% DMF‐H2O medium at 303 K and 0.1 M ionic strength, to investigate its ligation properties. Quantitative structure activity relationship (QSAR) and molecular orbital properties were evaluated by applying HyperChem 7.5 tools. The title compound and its Cu (II), Ni (II), and Zn (II) complexes were characterized by various spectro analytical tools, namely, Fourier‐transform infrared spectroscopy, 1H‐nuclear magnetic resonance, liquid chromatography‐mass spectrometry, UV‐Vis, thermogravimetric analysis–differential thermal analysis, scanning electron microscope (SEM)–energy‐dispersive X‐ray, electron spin resonance, and X‐ray diffraction (XRD) studies. Infrared data provided information about the chelating properties of ligand and coordination sites in metal complexes. The electronic spectral studies of complexes inferred the symmetry‐based spin allowed electronic transitions and charge transfer (CT) transitions. Mass spectral studies, elemental analysis, and thermal studies of complexes confirmed the composition of the metal complexes. The surface texture and nanocrystalline nature of solid compounds were studied by SEM and XRD methods. The antioxidant activities of all the compounds were determined by DPPH radical scavenging method. DNA‐binding interactions of the synthesized compounds with calf thymus (CT)‐DNA were studied by absorption and fluorescence methods. Antioxidant and antimicrobial studies indicated their potentiality as active agents. Cytotoxicity measurements of title compounds for IC50 values on MCF‐7 cell line, and docking scores of these compounds with chosen target, computed by employing AutoDock software indicated their potential for anticancer properties.

Electronic Absorption, Emission Spectral, and Electrochemical Studies of [Cu(OBTTAP)] Linked (bpy)2RuII, (phen)2RuII, and (PPh3)CpRuII Complexes

Electronic Absorption, Emission Spectral, and Electrochemical Studies of [Cu(OBTTAP)] Linked (bpy)2RuII, (phen)2RuII, and (PPh3)CpRuII Complexes

Synthesis, characterization, and in vitro antibacterial and cytotoxic study of Co(II), Ni(II), Cu(II), and Zn(II) complexes of N-(4-methoxybenzyl) N-(phenylethyl) dithiocarbamate ligand

Four new homoleptic complexes of Co(II) [C-1], Ni(II) [C-2], Cu(II) [C-3], and Zn(II) [C-4] derived from N-(4-methoxybenzyl) N-(phenylethyl) dithiocarbamate ligand (KL) with general formula ML2 were synthesized with good yield and characterized by elemental analysis and different spectroscopic techniques like FTIR, 1H and 13C NMR, HRMS, UV–vis and fluorescence spectroscopy. The crystal structure of the complex C-4 was determined by the single crystal X-ray diffraction technique (SC-XRD), which shows a distorted square pyramidal geometry around the Zn(II) ion. Thermogravimetric studies of all four complexes were performed and found that decomposition occurred in three steps and the final product of the thermal decomposition was metal sulfides. The magnetic properties of cobalt, nickel, and copper complexes were analyzed by a vibrating sample magnetometer (VSM) and the hysteresis of magnetization showed the paramagnetic nature of cobalt and copper complexes while the diamagnetic nature of the nickel complex. Electronic spectral studies of the ligand and all four complexes were recorded in methanolic solution and the spectra show the absorption for the ligand at 301 nm and the absorption band for complexes was observed in the range 265-275 nm which is due to intra-ligand charge transfer (ILCT) transitions. Complexes C-1, C-2, and C-3 showed transitions in the range of 325-445 nm due to ligand-to-metal charge transfer (LMCT) transitions. Anti-bacterial studies of all compounds were performed against Bacillus subtilis, Staphylococcus aureus, Clostridium sporogenes, and Escherichia coli and the result showed that complexes C-2 and C-4 have significant anti-bacterial properties. The cytotoxicity study of all compounds against breast cancer cell line MCF-7 shows that complex C-2 has a potential anti-cancerous property with the least IC50 value against normal cell line HEK-293.

Material of oxo-peroxo-molybdenum (VI) complex involving 4-Furoyl-3-methyl-1-phenyl-2-pyrazoline-5- one: experimental cum theoretical observations

We report here the experimental and theoretical investigation of the bis(4-furoyl-3-methyl-1-phenyl-2-pyrazolin-5-one)oxoperoxomolybdenum(VI) complex molecule. It was prepared by the reaction of (2:1) 4-furoyl-3-methyl-1-phenyl-2-pyrazolin-5-one and [MoO(O)2]2+ in an aqueous ethanol medium. Characterization was performed by elemental analysis, molar conductivity, magnetic measurements, electrochemical analysis, and infrared and electronic spectral studies. Theoretical validation was performed by density functional theory calculations using B3LYP as the LANL2DZ function. The molecular geometry results show a distorted pseudo-pentagonal bipyramidal geometry together with the O7 coordination mode around the Mo(VI) center. The FMO energies allow the determination of the atomic and molecular parameters and also represent the charge transfer across the molecule.

Molecular docking analysis and spectroscopic (FT-IR and UV–Vis) investigation of 2-(Trifluoromethyl) phenothiazine

For the current study, the electronic absorption spectrum of 2-(Trifluoromethyl) phenothiazine (2-TFMPTZ) is obtained experimentally and computationally from 200 to 400 nm in three solvents. The observed and theoretical FT-IR spectrum is obtained from 400 to 4000 cm−1 and thus various frequencies and vibrational modes are analyzed. The theoretical calculations are computed with density functional theory (DFT) employing B3LYP/6–311++G(d,p) basis set. The different vibrational modes are assigned by VEDA program. In the electronic spectral study, the wavelength maxima, excitation energy, oscillator strength, HOMO and LUMO energies are computed for the 2-TFMPTZ molecule. The thermodynamic parameters at different temperature range are computed using the vibrational frequencies. The electric dipole moment (µ), polarizability (α) and non–linear optical (NLO) first hyperpolarizability (β) have been computed to analyze the effect of the electric field. Molecular docking analysis has been performed to check the pharmacological usage of the 2-TFMPTZ ligand.

Synthesis and characterization of heterobinuclear Schiff base nickel(II) complexes involving nitrogen and oxygen donor ligand

This study reports the synthesis of five novel Schiff base heterobinuclear nickel(II) and tin(II) complexes. The heterobinuclear complexes were synthesized by the interaction of N,N′-ethylenebis(2-hydroxyacetophenoniminato) nickel(II) with tin(II) salts of 2,4,6-trinitrophenol, 1-nitroso-2-naphthol, o-nitrophenol, 8-hydroxyquinoline and 2,4-dinitrophenol. Characterization of these complexes was carried by physico-chemical techniques such as elemental analyses, conductivity measurements, magnetic measurements, infrared spectra and electronic spectral studies. The molar conductance data reveals that the complexes are non-electrolytic in nature. The magnetic susceptibility data and the spectral studies propose square planar geometry of the complexes around nickel(II) and coordination to the metal centre via azomethine nitrogen and deprotonated phenolic oxygen atoms.

Growth and physical property studies of a BioMOF: silver mandelate crystals for optical and dielectric applications

ABSTRACT Biological metal-organic frameworks (BioMOF) formed by coordinating metal ions with biologically derived organic ligands have rising scientific stature owing to their superior functionalities. In the current work silver mandelate crystals (Ag(C8H7O3)), a silver-based bio-MOF are grown in hydrosilica gel medium activated with mandelate anions. XRD pattern of the powdered crystal confirmed the crystallinity of the crystals and the diffraction pattern is matched with the reported card data. Raman and FTIR spectra analyses confirmed the formation of the compound and ensured the presence of various functional groups in the crystal. Thermogravimetric analysis (TGA) revealed the chemical formula of the grown crystal and Differential Thermal analysis (DTA) stated that the compound is thermally stable. The single-stage thermal degradation over the temperature range of 160–350°C shows the- final degraded product is crystalline silver. The electronic spectral studies of the grown crystals show that the optical band gap energy is 4.36 eV. The dielectric behaviour is examined by studying the variation of dielectric constant, conductivity, and dielectric loss with the frequency of the applied field.

Synthesis, Characterization and Biological Activity of Metal Chelates Based On 8-Hydroxyquinoline and 1, 2, 4-Triazol

The present study aims to synthesize a novel ligand namely, 5-((3-(trifluoromethyl)-1H-1,2,4-triazol-1-yl)methyl)-8-Hydroxyquinoline (TFMTHQ) by reacting 5-chloromethyl-8-hydroxyquinoline (CMQ) hydrochloride, a versatile derivative of 8-hydroxyquinoline with 3-trifluoromethyl-1-H-1,2,4-triazole. The co-ordinate metal chelates of the ligand TFMTHQ were prepared using divalent metal ions viz., Cu2+, Co2+, Ni2+, Mn2+, Zn2+ and Cd2+ by a simple method. The ligand TFMTHQ and its all metal chelates were duly characterized for elemental content, spectral features, M: L (metal: ligand) ratio, and magnetic moment. The results of electronic spectral studies and magnetic properties indicated octahedral geometry for all the metal chelates. All the synthesized compounds were tested for antibacterial activity against gram positive and gram negative bacteria. Antifungal activity of all the samples was tested against plant pathogens such as Aspergillus Niger (AN), Botrydepladia Thiobromine (BT), Nigrospora Sp. (NS), and Fusarium Oxyporium (FO). The results showed good antimicrobial activity of all the metal chelates.

Synthesis, Characterization and Antifungal Activity of Metal Chelates Based on 8-Hydroxyquinoline and Metronidazole

In the present study, 5-chloromethyl-8-hydroxyquinoline (CMQ) hydrochloride, a versatile derivative of 8-hydroxyquinoline is reacted with a potent antibiotic drug metronidazole in order to yield a novel ligand namely 5-((2-(2-methyl-5-nitro-1H-imidazol-1-yl) ethoxy) methyl)-8-hydroxyquinoline (NIHQ). The co-ordinate metal chelates of the ligand NIHQ were prepared using divalent metal ions viz., Cu2+, Co2+, Ni2+, Mn2+, Zn2+ and Cd2+ by simple method. The ligand NIHQ and its all metal chelates were duly characterized for elemental content, spectral features, M: L (metal: ligand) ratio, and magnetic moment. The results of electronic spectral studies and magnetic properties indicated octahedral geometry for all the metal chelates. Antifungal activity of all the samples was tested against plant pathogens such as Aspergillus niger, Botrydepladia thiobromine, Nigrospora Sp., and Fusarium oxyporium. The results showed promising antifungal activity of all the metal chelates.

Synthesis, Characterisation and Microbial Activity of 2-(1H-benzothiazol-2-yl) Thioacetic acid with some Bivalent Metal Ions

The complexes of the potassium salt of 2-mercaptobenzthiazole with potassium salt of 2-chloroacetic acid in aqueous dioxane at reflux temperatures result in the formation of potassium salt of 2-(1H- benzolthiazol-2-yl) thioacetic acid (K C9 H6 NO2 S2 =KL). The Ligand KL forms stable complexes with bivalent metal chloride in aqueous ethanol to form bisligated complexes [ML2 ]nH2 O [(M=Co(II), Ni(II), Mn(II), Cu(I), Zn(II), or Cd(II) and n=o, 2 or 4)]. The Magnetic susceptibility and electronic spectral studies of Co(II), Mn(II), Ni(II), and Cu(II) complexes resemble their octahedral or distorted octahedral structure of these metal ions. The i. r spectral bands positions of complexes indicated that benzothiazole part of the ligand is not involved in coordination. The antifungal activity of ligand and its complexes were examined by cup and disc method. The results do not show appreciable antifungal activity examined by cup and disc method. The results do not show appreciable antifungal activity examined on fungi. The thermal stability of complexes indicated that two water molecules in Co(II), Ni(II) Cu (II) and Mn(II) Complexes [ML2 (H2 O)2]2H2 O are present in coordination sphere.

Synthesis, Characterization and Biological Studies of Bimetallic Complexes Containing Co(II), Cd(II) and Hg(II) and {N, N’,-Bis (Benzylidene)-1,3,-Diamine} Schiff Base in 1:2 Ratio

A new series of bimetallic complexes of Co(II), Cd(II) and Hg(II) with Schiff base ligand (N,N',-Bis(Benzylidene)-1,3-Phenylenediamine, {BENDAMB (1,3)} have been synthesized and characterized by elemental analysis, molar conductance, magnetic moment measurements, IR, Electronic and 1H NMR spectral studies. The softness parameter TEn of complexes have also been calculated to derive the binding side of the thiocyanate ligand. The spectral data shows that the Schiff base ligand is linked with comparatively harder metal Co2+ whereas SCN present as terminal. Magnetic susceptibility measurements indicate tetrahedral geometry around Cobalt ion. The softness parameter, suggest cationic-anionic structure for these complexes. Newly synthesized bimetallic complexes have been screened, for their antimicrobial and antifungal activities and was compared with solvent and Schiff base, screening results indicates that, the metal complexes are moderately active compared with those of pure Schiff base, BENDAMB (1,3).

Syntheses, spectral, thermal and pH-metric studies on bivalent metal ion complexes of N,N’-bis(3-carboxy-1-oxo-z-prop-2-elenyl)ethylenediamine

A novel carboxyamide ligand has been synthesized using maleic anhydride and ethylenediamine. Co(II), Ni(II), Cu(II) and Pd(II) complexes of the ligand, i.e., N,N’-bis(3-carboxy-1-oxo-z-prop-2-elenyl)ethylenediamine [H2L] have been prepared and characterized by elemental analyses, IR, electronic, 1H NMR, EPR spectral and thermal studies. It is revealed by IR and 1H NMR spectral studies that the ligand coordinated to the metal ions through deprotonated carboxylate oxygen and non-deprotonated amide nitrogen in all the complexes. It is suggested by electronic spectral and magnetic moment studies that N2O2 coordination is around each metal center with a strong field square planar chromophore. All the complexes have been studied by TGA and DTA studies done simultaneously. The complex formation between ligand and metal ions [Mn(II), Co(II), Ni(II), Cu(II) and Zn(II)] has also been studied pH metrically in 75% aqueous DMF solution at 298 K in 0.1 M NaClO4. The probable structures of the complexes have also been proposed.

Coordination Chemistry, Antibacterial Screening, and In Silico ADME Study of Mononuclear NiII and CuII Complexes of Asymmetric Schiff Base of Streptomycin and Aniline

Two novel metal complexes, that is, Ni (StmAn)2(4) and Cu (StmAn)2(5), were synthesized from unsymmetrical Schiff base ligand StmAn (3). The ligand was prepared by refluxing streptomycin (2) and aniline (1). They were characterized by elemental microanalysis, conductivity measurements, and spectroscopic techniques such as 1H NMR, FT-IR, ESI-mass, and electronic absorption spectral study. Interestingly, the study revealed metal coordination through azomethine nitrogen and N-atom of NH-CH3 of N-methyl-L-glucosamine unit of streptomycin. The electronic absorption spectral study supported an octahedral geometry for complex 4 and a tetrahedral geometry for complex 5. Particle size calculation by Scherrer’s formula indicated their nanocrystalline nature. The geometry optimization of the complexes was achieved by running an MM2 job in Gaussian supported Cs-ChemOffice ultra-12.0.1 and ArgusLab 4.0.1 version software. Based on SwissADME predictions, a theoretical drug profile was generated by analyzing absorption, distribution, metabolism, excretion, and toxicity (ADMET) scores of the compounds. They were screened for in vitro antibacterial activity study against four clinical pathogens such as E. coli, S. pneumoniae, P. vulgaris, and S. aureus. Minimum inhibitory concentration (MIC) study demonstrated greater inhibitory potency of complex (4) (0.024 g/L) for S. aureus relative to ligand (3) and complex (5). Studies show that metal complexes are more toxic to bacteria.

Nickel (II), Copper (II), and Zinc (II) Complexes of N-bis (4-methoxybenzyl) Dithiocarbamate: Synthesis, Characterization Studies, and Evaluation of Antitumor Activity

Three new complexes with the general formula [M(L)2] (L=N-bis(4-methoxybenzyl) dithiocarbamate; M= Ni(II) 1, Cu(II) 2, and Zn(II) 3 ), have been synthesized, and characterized by elemental analysis, IR, UV–visible, 1H, 13C NMR and mass spectrometry. The magnetic behavior of nickel and copper complexes was measured and found to be diamagnetic and paramagnetic, respectively. Complex 3 crystallized in the monoclinic space group P21/c and possessed a centrosymmetric dimeric structure stabilized by weak C-H···S, C-H···π, and C-H…O intermolecular interactions. Electronic absorption spectral studies of the complexes show the absorption band in the range of 270-331 nm, which is due to intraligand charge transfer transitions. Complexes 1 and 2 also show transitions in the range of 325-475 nm due to ligand to metal charge transfer transition. The antitumor activities of the complexes have been screened, and the results obtained show that the metal complexes have significant antitumor activity against Dalton's lymphoma cells in a concentration-dependent manner, and the metal complexes were relatively tolerant to normal human cells with low or marginal toxicity against both lymphocytes and monocytes.