Reduced Schiff Base Research Articles

ChemInform Abstract: Anion Recognition by Simple Chromogenic and Chromo‐Fluorogenic Salicylidene Schiff Base or Reduced‐Schiff Base Receptors

AbstractReview: 41 refs.

Bis(quinolin-2-ylcarbon-yl)amido-κ(3) N,N',N'']bromido-(N,N-di-methyl-formamide-κO)copper(II).

In the mononuclear title complex, [CuBr(C20H12N3O2)(C3H7NO)], synthesized from the quinoline-derived reduced Schiff base 4-(quinolin-2-ylmeth­yl)amino­phenol, the coordination geometry around Cu2+ is distorted square-pyramidal, comprising a bromide anion at the apex [Cu—Br = 2.4671 (5) Å]. The base of the pyramid is built up from one di­methyl­formamide O-atom donor [Cu—O = 2.078 (2) Å] and three N-atom donors from the monoanionic, tridentate bis­(quinolin-2-ylcarbon­yl)di­imide ligand [Cu—Ndi­imide = 1.941 (3) Å, and Cu—Nquinol­yl = 2.060 (3) and 2.049 (3) Å]. An intra­molecular C—H⋯O occurs. In the crystal, weak methyl and aromatic C—H⋯Br and formyl C—H⋯Ocarbon­yl hydrogen-bonding inter­actions generate an overall layered structure lying parallel to (001).

Design and synthesis of enantiomeric (R)- and (S)-copper(II) and diorganotin(IV)-based antitumor agents: Their in vitro DNA binding profile, cleavage efficiency and cytotoxicity studies

New chiral reduced Schiff base ligands (R)/(S)-2-(2-hydroxy-1-phenylethylaminomethyl)phenol (L), (R)/(S)-2-(benzylamino)-2-phenylethanol (L′) and their Cu(II)/organotin(IV) complexes (1–4) were synthesized and thoroughly characterized. Preliminary in vitro DNA binding studies of (R)- and (S)-enantiomeric pairs of ligands L, L′ and complexes 1–4 were carried out employing UV–vis, fluorescence and circular dichroic techniques to evaluate their enantioselective DNA binding potential, thereby to act as antitumor chemotherapeutic drug entities. The observations demonstrated that S-enantiomer of Cu(II) complex, 1 binds more avidly to DNA in comparison to its R-enantiomeric form and organotin(IV) complex 2. This was further established by Kb and Ksv values of ligands L and L′ and (S)-/(R)-1–4 complexes, which demonstrated multifold increase in case of S-enantiomer of copper complex 1 in comparison to its R-enantiomeric form. This clearly demonstrates the chiral preference of S-enantiomer over R-enantiomer and its potency to act as a chemotherapeutic agent. Cleavage studies of 1–4 with pBR322 plasmid DNA were carried out, noticeably, S-enantiomer of complex 1 exhibited effective DNA cleavage efficiency in absence of external agents. The cytotoxicity of ligands L and L′ and (S)-/(R)-1–4 complexes was examined on a panel of 19 human tumor cell lines of different histological origins by SRB assay. In the both the cases, the S-enantiomer of complex 1 and 3 revealed remarkably good cytotoxic activity (GI50 values <10) against T24 (Urinary Bladder), DU145 (Prostate), U373MG (Astrocytoma) and HCT15, SW620 (Colon) clearly underlining the influence of enantiomeric discrimination. Interestingly, ligands L, L′ and rest of the complexes demonstrated moderate cytotoxic activity (GI50 values <40).

Carbonic anhydrase inhibitors. Inhibition of human cytosolic isoforms I and II with (reduced) Schiff’s bases incorporating sulfonamide, carboxylate and carboxymethyl moieties

A library of Schiff bases was synthesized by condensation of aromatic amines incorporating sulfonamide, carboxylic acid or carboxymethyl functionalities as Zn2+-binding groups, with aromatic aldehydes incorporating tert-butyl, hydroxy and/or methoxy groups. The corresponding amines were thereafter obtained by reduction of the imines. These compounds were assayed for the inhibition of two cytosolic human carbonic anhydrase (hCA, EC 4.2.1.1) isoenzymes, hCA I and II. The Ki values of the Schiff bases were in the range of 7.0–21,400nM against hCA II and of 52–8600nM against hCA I, respectively. The corresponding amines showed Ki values in the range of 8.6nM–5.3μM against hCA II, and of 18.7–251nM against hCA I, respectively. Unlike the imines, the reduced Schiff bases are stable to hydrolysis and several low-nanomolar inhibitors were detected, most of them incorporating sulfonamide groups. Some carboxylates also showed interesting CA inhibitory properties. Such hydrosoluble derivatives may show pharmacologic applications.

Synthesis, crystal structures and characterizations of two homochiral coordination polymers based on a chiral reduced Schiff base ligand

Two homochiral coordination polymers based on a chiral reduced Schiff base ligand, namely poly[(μ5-4-{[(NR,1S)-(1-carboxylato-2-phenylethyl)amino]methyl}benzoato)zinc(II)], [Zn(C17H15NO4)]n, (1), and poly[(μ5-4-{[(NR,1S)-(1-carboxylato-2-phenylethyl)amino]methyl}benzoato)cobalt(II)], [Co(C17H15NO4)]n, (2), have been obtained by hydrothermal methods and studied by single-crystal X-ray diffraction, elemental analyses, powder X-ray diffraction, thermogravimetric analysis, IR spectroscopy and fluorescence spectroscopy. Compounds (1) and (2) are isostructural and crystallize in the P2(1)2(1)2(1) space group. Both display a three-dimensional network structure with a one-dimensional channel, with the benzyl group of the ligand directed towards the channel. An investigation of photoluminescence properties shows that compound (1) displays a strong emission in the purple region.

Synthesis, crystal structures, spectroscopic and electrochemical studies on Cu(II) and Ni(II) complexes with compartmental nitrogen–oxygen mixed donor ligands

The synthesis and characterization of two new N2O4 donor type ligands, 2-{[(2-{3-[2-({[(2-hydroxyphenyl)methylidene]amino}methyl)phenoxy]propoxy}benzyl)imino]methyl}phenol (H2L1) and 2-[({2-[3-(2-{[(2-hydroxybenzyl)amino]methyl}phenoxy)propoxy]benzyl}amino)methyl]phenol (H2L2), and their metal complexes with Cu(II) and Ni(II) metal ions are reported. The ligands and complexes have been characterized by 1H NMR, FT-IR, UV–Vis absorption spectroscopy, single-crystal X-ray diffraction, CHN elemental analysis and cyclic voltammetry (CV). The redox behavior of the two complexes has been studied by CV. Copper and nickel complexes of Schiff base (H2L1) and reduced Schiff base (H2L2) showed different behaviors because the structure of the complexes depends of the ligand. The complex [Cu2L12]·2CH3OH (1) is dinuclear with the two metal centers bridged exclusively by the ligands, consisting of two distorted square planar CuN2O2 chromophors with large intermetallic separation (8.879Å). Complex [Ni4L22(CH3COO)4]·4CH3OH (2) consists of tetranuclear Ni4 unit of two symmetry related hexacoordinated nickel atoms having distorted octahedral NiN2O4 and NiO6 environments, and contains two types of acetate coordination modes, namely, bridging bidentate (μ2-η1, η1), and asymmetric chelating bridging (μ2-η2, η1).

Influence of inductive effects and steric encumbrance on the catecholase activities of copper(ii) complexes of reduced Schiff base ligands

A series of copper(ii) complexes derived from reduced Schiff base ligands has been synthesized and characterized by single-crystal X-ray diffraction and spectroscopic analyses. With the exception of [Cu(Ala5NO2)(H2O)] (), which crystallized as a mononuclear repeating unit, [Cu2L2(H2O)x(DMSO)y]·solvent (L = Ala5H (), Ala5OMe (), Ala5Cl (), Ala5Br (), Gly5Br (), Val5Br () and Leu5Br (), x = 1 or 2, y = 0 or 1, solvent = MeOH or DMSO and H2O) crystallized as phenoxo-bridged dinuclear building units containing Cu2O2 cores. In , , , and , the axial positions are occupied by solvent ligands and carboxylate oxygen atoms from adjacent dimers, resulting in the formation of 1D helical coordination polymers. In , a 2D network is constructed by utilizing weak CuO interactions (∼2.7 Å) with carboxylate groups. All complexes have been investigated for their catecholase activities with 3,5-DTBC, and they show significant catalytic activities except for . The catalytic activities are also observed to increase with increasing +I effects, as well as increase with increasing steric bulkiness on the α-carbon of the carboxylate group.

A trinuclear Cu2Eu complex catalyzed asymmetric Friedel–Crafts alkylations of indoles with nitroalkenes

Catalytic enantioselective Friedel–Crafts alkylations of indoles and nitroalkenes were carried out by using a new heterotrimetallic Cu/Eu/Cu complex catalyst based on the simple chiral ligand, reduced Schiff base 1, to give the Friedel–Crafts adducts with up to 88% yield and 80% ee. The trimetallic catalyst is air-stable and can be formed in-situ by a facile solution self-assembly during the catalytic reaction.

Ten complexes constructed by two reduced Schiff base tetraazamacrocycle ligands: syntheses, structures, magnetic and luminescent properties

Ten new complexes, [Cu2(L1)(NO3)2]·2H2O (1), [Cu4(L1)2]·4ClO4·H2O (2), [Cu2(L1)(H2O)2]·(adipate) (3), [Cu6(L1)2(m-bdc)4]·2DMF·5H2O (4), [Cu2(L1)(Hbtc)]·5H2O (5), [Cu2(L1)(H2O)2]·(ntc)·3H2O (6), [Co2(L2)]·[Co(MeOH)4(H2O)2] (7), [Co3(L2)(EtOH)(H2O)] (8), [Ni6(L2)2(H2O)4]·H2O (9) and [Zn4(L2)(OAc)2]·0.5H2O (10), have been synthesized. 1 displays a [Cu2(L1)(NO3)2] monomolecular structure. 2 shows a supramolecular chain including [Cu2L1]2+. In 3, two Cu(II) ions are connected by L1 to form a [Cu2(L1)(H2O)2]2+ cation. In 4, the m-bdc anions bridge Cu(II) ions and L1 anions to form a layer. Both 5 and 6 display 3-D supramolecular structures. 7 consists of both [Co2L2]2− and [Co(MeOH)4(H2O)2]2+ units. 8 and 9 show infinite chain structures. In 10, Zn(II) dimers are linked by L2 to generate a 3-D framework. The magnetic properties for 4 and 8 and the luminescent property for 10 have been studied.

Interaction of anticancer reduced Schiff base coumarin derivatives with human serum albumin investigated by fluorescence quenching and molecular modeling

The specific binding of five reduced Schiff base derived 7-amino-coumarin compounds with antitumor activity to human serum albumin, the principal binding protein of blood, was studied by fluorescence spectroscopy. Their conditional binding constants were computed and the reversible binding at the Sudlow’s site I was found to be strong (KD∼0.03–2.09μM). Based on the data albumin can provide a depot for the compounds and is responsible for their biodistribution and transport processes. The experimental data is complemented by protein–ligand docking calculations for two representatives which support the observations. The proton dissociation constants of the compounds were also determined by UV–Vis spectrophotometric and fluorometric titrations to obtain the actual charges and distribution of the species in the various protonation states at physiological pH.

MOFs with 5-aminoisophthalate and 4,4′-bipy or a reduced Schiff base dicarboxylate

MOFs with 5-aminoisophthalate and 4,4′-bipy or a reduced Schiff base dicarboxylate

Cytotoxic, cell apoptosis and DNA binding properties of some ternary Cu(II) complexes with a reduced Schiff base ligand and heterocyclic bases

Abstract Three mononuclear mixed ligand Cu(II) complexes of the type [Cu(L)(DTHA)]H2O⋅CH3OH, where H2DTHA is 2-(3,5-di-tert-butyl-2-hydroxybenzylamino) acetic acid and the co-ligand L is 1,10-phenanthroline (phen, 1), dipyrido[3,2-d:2′,3′-f]quinoxaline (dpq, 2) dipyrido [3,2-a:2′,3′-c]phenazine (dppz, 3) have been isolated and characterized. Absorption and emission spectral studies and viscosity measurements indicated that 3 interacts with DNA more strongly than all of the other complexes through intercalation mode. Furthermore, cytotoxicity studies on the tested four cell line indicated that they can efficiently inhibit the cell proliferation in a time-dependent manner, and the Hoechst 33258 staining assays have also been employed in finding the extent of DNA damage.

Eight coordination compounds based on a reduced Schiff base tetraaminodiphenol macrocyclic ligand

Eight new compounds, namely, [Cu2(L)]·2NO3·H2O (1), [Cu(ox)2]·0.5(H6L)·3H2O (2), [Zn(L)0.5(nds)0.5] (3), [Zn4(L)2(m-bdc)2]·0.5H2O (4), [Cd(L)0.5(ox)0.5(H2O)]·MeOH·1.25H2O (5), [Cd(L)0.5(H2O)3]·0.5(p-bdc)·1.5H2O (6), [Cd2(L)(btec)0.5(H2O)4]·2.5MeOH·H2O (7) and [Ni2(L)(btec)0.5(H2O)]·MeOH·1.5H2O (8) (H2L=10,21-dimethyl-3,6,14,17-tetraazatricyclo [17.3.18,12]tetracosa-1(23),8,10,12(24),19,21-hexaene-23,24-diolate, ox=oxalate, nds=1,5-naphthalenedisulfonate, m-bdc=1,3-benzenedicarboxylate, p-bdc=1,4-benzenedicarboxylate and btec=1,2,4,5-benzenetetracarboxylate), have been synthesized. In compound 1, the L ligand coordinates with two Cu(II) atoms to form a [Cu2L]2+ unit. In compound 2, two ox anions chelate to one Cu(II) atom to form a [Cu(ox)2]2− unit. The (H6L)4+ acts as a counter ion. The whole structures of 1 and 2 feature three-dimensional (3D) supramolecular architectures connected by weak Cu⋯O and hydrogen-bonding interactions, respectively. In compounds 3–5, the [M2L]2+ cations are bridged by nds, m-bdc and ox anions to form chains, respectively. The chains of 3 and 4 are further linked by hydrogen-bonding interactions into 2D and 3D supramolecular architectures, respectively. In compound 6, the macrocyclic L anion coordinates to two Cd(II) atoms to form a [Cd2L]2+ cation. The final structure of 6 exhibits a 3D supramolecular architecture linked by hydrogen bonds. In compound 7, Cd(II) atoms are linked by L anions to form two types of [Cd2L]2+ cations. One type of [Cd2L]2+ cations are bridged by btec anions to generate a polymeric anion chain, whereas the other [Cd2L]2+ cations are free. Further, the polymeric anion chains and the [Cd2L]2+ cations are linked by hydrogen bonds to generate a 2D supramolecular layer. In compound 8, btec anion bridges the [Ni2L]2+ cations to yield a 2D layer. Thermogravimetric analyses (TGA) for the compounds 1–8 have been investigated. In addition, the magnetic property for 1 and the luminescent properties for compounds 3–7 have also been studied.

Syntheses, crystal structures, and characterization of four homochiral coordination polymers based on two chiral reduced Schiff base ligands

Four homochiral coordination polymers incorporating two chiral reduced Schiff base ligands, namely, [Cu(L1)(H2O)]·H2O (1), [Zn2(L2)2] (2), [Co(L2)(H2O)] (3), and [Ni(L2)(H2O)] (4) (H2L1 = N-(4-carboxyl)benzyl-l-alanine, H2L2 = N-(4-carboxyl)benzyl-l-leucine) have been obtained by hydrothermal methods and characterized by physico-chemical and spectroscopic methods. X-ray crystallographic analysis reveals that complex 1 exhibits a chain structure with 1D channels. Complexes 2–4 all are 3D network structures with 1D channels in which the isobutyl group of the ligand points toward to the channel. Complex 2 displays strong photoluminescent emission in the purple region.

Retention of Cs–Cl bond induces coordination polymer formation over trinuclear chiral assembly of copper(ii) complexes of l-leucine derived ligand

The use of caesium is a less trodden path in terms of the synthesis of coordination polymers. The chemical similarity and mild toxic nature of caesium salts does not provide much impetus to work with these compounds compared to their potassium analogues. However, are the potassium and caesium salts really close in terms of coordination polymer formation? The result presented in this manuscript shows that while neither potassium halides or potassium nitrate inhibit the formation of a trinuclear chiral assembly of a copper(II) complex from a mononuclear Cu(II) complex, caesium chloride preferentially forms a coordination polymer while keeping the Cs–Cl bond intact. Under the same conditions, caesium nitrate does not inhibit the assembly formation. Structural characterization of {[CsCl{Cu(HLL-leu)2}(H2O)]}n (2) showed it to be a two-dimensional coordination polymer in the ab plane, where penta-coordinated Cu(HLL-leu)2 complex units (HLL-leu = reduced Schiff base of L-leucine and the salicylaldehyde condensation product) were interconnected through the formation of Cu–Cl–Cs bonds. Multitudes of intermolecular H-bonds were observed as well. The use of KCl, KBr, KI or CsNO3 in lieu of CsCl to the [Cu(HLL-leu)2(CH3CN)] (1) facilitated the formation of the trinuclear assembly, [M{Cu(HLL-leu)2}3]X, where M = K+ or Cs+ and X = Cl, Br, I or NO3 depending on the salt used. The Cu(HLL-leu)2 units in these assemblies are hexacoordinated Cu(II) complexes.

Zinc(II) and cadmium(II) coordination polymers with a tricarboxylate containing reduced Schiff base ligand: Structural characterization and luminescent property

Three new coordination polymers, [Cd(HL)(phen)]·2H2O (1), [Zn2(L)(HCOO)(bpy)2]·H2O (2) and [Zn2(L)(μ3-OH)(bpy)]·1.5H2O (3) [H3L=5-(4-carboxybenzylamino)isophthalic acid, phen=1,10-phenanthroline and bpy=2,2′-bipyridine], have been prepared and characterized by single crystal and powder X-ray diffraction, IR, elemental and thermogravimetric analyses. Complex 1 displays a 1D neutral double-stranded chain structure. Complex 2 shows the uninodal 3-connected 2D (4.82) fes network with in-situ generated [Zn2(COO)2(bpy)2] as the secondary building unit (SBU). Complex 3 exhibits the 2-nodal (3,6)-connected 2D (43)2(46.66.83) kgd net architecture containing in-situ generated [Zn4(COO)4(μ3-OH)2(bpy)2] (SBU). Significantly, concrete hexanuclear clusters (Zn4O2) exist in 3. Taking hydrogen bonding interactions into account, extended 3D supramolecular frameworks of 1–3 can be built. The influences of the coordination modes of the ligand, coordination geometries of the metal centers, steric hindrance as well as reaction temperature on the structures of the resultant complexes are discussed. Furthermore, the luminescent properties of 1–3 were preliminarily investigated.

Amino Alcohol-Derived Reduced Schiff Base VIVO and VV Compounds as Catalysts for Asymmetric Sulfoxidation of Thioanisole with Hydrogen Peroxide

We report the synthesis and characterization of several amino alcohol-derived reduced Schiff base ligands (AORSB) and the corresponding V(IV)O and V(V) complexes. Some of the related Schiff base variants (amino alcohol derived Schiff base = AOSB) were also prepared and characterized. With some exceptions, all compounds are formulated as dinuclear compounds {V(IV)O(L)}(2) in the solid state. Suitable crystals for X-ray diffraction were obtained for two of the AORSB compounds, as well as a rare X-ray structure of a chiral V(IV)O compound, which revealed a dinuclear {V(IV)O(AOSB)}(2) structure with a rather short V-V distance of 3.053(9) Å. Electron paramagnetic resonance (EPR), (51)V NMR, and density functional theory (DFT) studies were carried out to identify the intervenient species prior to and during catalytic reactions. The quantum-chemical DFT calculations were important to determine the more stable isomers in solution, to explain the EPR data, and to assign the (51)V NMR chemical shifts. The V(AORSB) and V(AOSB) complexes were tested as catalysts in the oxidation of thioanisole, with H(2)O(2) as the oxidant in organic solvents. In general, high conversions of sulfoxide were obtained. The V(AOSB) systems exhibited greater activity and enantioselectivity than their V(AORSB) counterparts. Computational and spectroscopic studies were carried out to assist in the understanding of the mechanistic aspects and the reasons behind such marked differences in activity and enantioselectivity. The quantum-chemical calculations are consistent with experimental data in the assessment of the differences in catalytic activity between V(AOSB) and V(AORSB) peroxido variants because the V(AORSB) peroxido transition states correspond to ca. 22 kJ/mol higher energy activation barriers than their V(AOSB) counterparts.

Insertion of a Hydroxido Bridge into a Diphenoxido Dinuclear Copper(II) Complex: Drastic Change of the Magnetic Property from Strong Antiferromagnetic to Ferromagnetic and Enhancement in the Catecholase Activity

A diphenoxido-bridged dinuclear copper(II) complex, [Cu(2)L(2)(ClO(4))(2)] (1), has been synthesized using a tridentate reduced Schiff base ligand, 2-[[2-(diethylamino)ethylamino]methyl]phenol (HL). The addition of triethylamine to the methanolic solution of this complex produced a novel triple bridged (double phenoxido and single hydroxido) dinuclear copper(II) complex, [Cu(2)L(2)(OH)]ClO(4) (2). Both complexes 1 and 2 were characterized by X-ray structural analyses, variable-temperature magnetic susceptibility measurements, and spectroscopic methods. In 1, the two phenoxido bridges are equatorial-equatorial and the species shows strong antiferromagnetic coupling with J = -615.6(6.1) cm(-1). The inclusion of the equatorial-equatorial hydroxido bridge in 2 changes the Cu···Cu distance from 3.018 Å (avg.) to 2.798 Å (avg.), the positions of the phenoxido bridges to axial-equatorial, and the magnetic coupling to ferromagnetic with J = 50.1(1.4) cm(-1). Using 3,5-di-tert-butylcatechol as the substrate, the catecholase activity of the complexes has been studied in a methanol solution; compound 2 shows higher catecholase activity (k(cat) = 233.4 h(-1)) than compound 1 (k(cat) = 93.6 h(-1)). Both complexes generate identical species in solution, and they are interconvertible simply by changing the pH of their solutions. The higher catecholase activity of 2 seems to be due to the presence of the OH group, which increases the pH of its solution.

Photocytotoxic ferrocene-appended (l-tyrosine)copper(II) complexes of phenanthroline bases

Copper(II) complexes of ferrocene(Fc)-conjugated reduced Schiff base of l-tyrosine (Fc-TyrH), viz., [Cu(Fc-Tyr)(L)](ClO4), where L is 1,10-phenanthroline (phen, 1), dipyrido[3,2-d:2′,3′-f]quinoxaline (dpq, 2), dipyrido[3,2-a:2′,3′-c]phenazine (dppz, 3) and 2-(naphthalen-1-yl)-1H-imidazo[4,5-f][1,10]phenanthroline (nip, 4), were prepared and tested for their photocytotoxicity in cancer cells. [Cu(Fc-Phe)(phen)](ClO4) (5) of l-phenylalanine and [Cu(Ph-Tyr)(L)(ClO4)] of the reduced Schiff base Ph-TyrH derived from benzaldehyde and l-tyrosine having phen (6) and dppz (7), and [Cu(Ph-Phe)(phen)(ClO4)] (8) using l-phenylalanine were prepared and used as controls. Complexes 5 and 6 were structurally characterized by X-ray crystallography. A copper(II)-based d–d band near 600nm and a ferrocenyl band at ∼450nm were observed in DMF–Tris–HCl buffer (1:4v/v) in respective complexes. The complexes are photocleavers of pUC19 DNA in visible light forming •OH radicals. They are cytotoxic in HeLa (human cervical cancer) and MCF-7 (human breast cancer) cells showing an enhancement of cytotoxicity in visible light. Fluorescence imaging shows nuclear localization of the complexes.

Synthesis, crystal structure, DNA-binding properties, cytotoxic and antioxidation activities of several ternary copper(II) complexes with a new reduced Schiff base ligand

Three new ternary copper(II) complexes, [Cu2(phen)2(PDIMAla)(H2O)2](ClO4)2·CH3OH (1), [Cu2(dpq)2(PDIMAla)(H2O)2](ClO4)2·CH3OH (2) and [Cu2(dppq)2(PDIMAla)(H2O)2](ClO4)2·CH3OH (3) (phen=1,10-phenanthroline, dpq=dipyrido[3,2:2′,3′-f]quinoxaline, dppz=dipyrido[3,2-a:2′,3′-c]phenazine, H2PDIMAla=N,N′-(p-xylylene)di-alanine acid) have been synthesized and the complex 1 has been structurally characterized by single-crystal X-ray crystallography, spectrometric titrations, ethidium bromide displacement experiments, CD (circular dichroism) spectral analysis and viscosity measurements. The results indicate that the three compounds, especially the complex 3, can strongly bind to calf-thymus DNA (CT–DNA). The intrinsic binding constants Kb of the ternary copper(II) complexes with CT–DNA are 0.38×105, 1.4×105 and 7.8×105 for 1, 2 and 3, respectively. Comparative cytotoxic activities of the copper(II) complexes are also determined by acid phosphatase assay. The results show that the ternary copper(II) complexes have significant cytotoxic activity against the human hepatic (HepG2), human promyelocytic leukemia (HL60) and human prostate (PC3) cell lines. Investigation of antioxidation property show that all the copper(II) complexes have strong scavenging effects for hydroxyl radicals.