Synthesis,crystal structure,and antibacterial activity of mononuclear nickel(II) and cobalt(III) Schiff-base complexes

Four new mononuclear complexes, [Ni(L¹)(NCS)₂] (1), [Ni(L²)(NCS)₂] (2), [Co(L¹)(N₃)₂]ClO₄ (3), and [Co(L²)(N₃)₂]ClO₄ (4), where L¹ and L² are N,N′-bis[(pyridin-2-yl)methylidene]butane-1,4-diamine and N,N′-bis[(pyridin-2-yl)benzylidene]butane-1,4-diamine, respectively, have been prepared. The syntheses have been achieved by reaction of the respective metal perchlorate with the tetradentate Schiff bases, L¹ and L², in presence of thiocyanate (for 1 and 2) or azide (for 3 and 4). The complexes have been characterized by microanalytical, spectroscopic, single crystal X-ray diffraction and other physicochemical studies. Structural studies reveal that 1–4 are distorted octahedral geometries. The antibacterial activity of all the complexes and their constituent Schiff bases have been tested against Gram-positive and Gram-negative bacteria.     

Synthesis,crystal structure and antibacterial activity of manganese(III) and cobalt(III) complexes containing pentadentate Schiff bases of a common amine and thiocyanate

Abstract

Four new mononuclear Schiff base manganese(III) and cobalt(III) complexes viz. [Mn(L¹)(NCS)] (1), [Mn(L²)(NCS)] (2), [Co(L³)(NCS)] (3), and [Co(L⁴)(NCS)]·0.5CH₃OH·0.5H₂O (4), containing thiocyanate as a common pseudohalide ion are reported. The pentadentate Schiff base ligands H₂L¹, H₂L², H₂L³, and H₂L⁴ were obtained by the condensation of substituted salicylaldehydes with N-(3-aminopropyl)-N-methylpropane-1,3-diamine. The syntheses of the complexes have been achieved by the reaction of manganese(II) perchlorate or cobalt(II) perchlorate with the respective Schiff bases in the presence of thiocyanate in methanol medium. Complexes 1–4 have been characterized by microanalytical, spectroscopic, single-crystal X-ray diffraction and other physicochemical studies. Structural studies reveal that 1–4 adopt nearly similar structures containing the MN₄O₂ (M?=?Mn, Co) chromophore in which each central M(III) ion adopts a distorted octahedral geometry. Weak intermolecular H-bonding interactions are operative in these complexes to bind the molecular units. The antibacterial activity of 1–4 and their constituent Schiff bases has been tested against some common bacteria.     

Copper complexes with a flexible piperazinyl arm: nuclearity driven catecholase activity and interactions with biomolecules

Three new Cu(II) complexes, [Cu(HL¹)(pyridine)(H₂O)](ClO₄)₂·2MeOH (1), [Cu₂(HL¹)₂(NO₃)₂](NO₃)₂·3H₂O (2) and [Cu(HL₂)(NO₃)₂]·MeCN (3), have been synthesized from two Schiff base ligands [HL¹ = 1-phenyl-3-((2-(piperazin-4-yl)ethyl)imino)but-1-en-1-ol and HL² = 4-((2-(piperazin-1-yl)ethyl)imino)pent-2-en-2-ol] using the chair conformer of a flexible piperazinyl moiety. Structural analysis reveals that 1 and 3 are monomeric Cu(II) complexes consisting of five- and six-coordinate Cu(II), respectively, whereas 2 is a dinuclear Cu(II) complex consisting of two different Cu(II) centers, one square planar with the other distorted octahedral. Screening tests were conducted to quantify the binding of 1–3 towards DNA and BSA as well as the DNA cleavage activity of these complexes using gel electrophoresis. Enzyme kinetic studies were also performed for the complexes mimicking catecholase-like activities. Antibacterial activities of these complexes were also examined towards Methicillin-Resistant Staphylococcus aureus bacteria. The results reflect that 2 is more active than the monomeric complexes, which is further corroborated by density functional theory study.     

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.     

Cu(II) complexes with 4-amino-3,5-dimethyl isoxazole and substituted aromatic aldehyde Schiff bases: synthesis,crystal structure,antimicrobial activity,DNA binding and cleavage studies

Three isoxazole Schiff bases 2-((E)-(3,5-dimethylisoxazol-4-ylimino)methyl)-6-methoxyphenol (L¹), 2-((E)-(3,5-dimethylisoxazol-4-ylimino)methyl)-4,6-diiodophenol (L²), 2-((E)-(3,5-dimethylisoxazol-4-ylimino)methyl)-6-bromo-4-chlorophenol (L³), and their Cu(II) complexes [Cu(L¹)₂] (1), [Cu(L²)₂] (2) and [Cu(L³)₂] (3) were synthesized. All the complexes have been characterized by elemental analysis, FT-IR, ESI mass, UV-Visible, ESR, TGA, magnetic moments, and single-crystal X-ray diffraction analysis. Based on analytical data, a square planar geometry is assigned to the Cu(II) complexes with N₂O₂ donors from the Schiff base ligands. The single-crystal X-ray diffraction measurements of 1 and 2 confirmed the square planar geometry. DNA binding studies from electronic absorption titrations, viscosity measurements, and fluorescence quenching studies indicated an intercalation mode of binding of Cu(II) complexes with CT-DNA. DNA cleavage experiments of Cu(II) complexes with supercoiled plasmid pBR322 DNA have also been investigated by agarose gel electrophoresis in the presence of H₂O₂ (oxidative cleavage) and UV light (photolytic cleavage). The synthesized compounds were screened for antibacterial (Escherichia coli, Pseudomonas putida, Klebsiella pneumoniae, Bacillus subtillis and Staphylococcus aureus) and antifungal (Candida albicans and Aspergillus niger) activities by the paper disk method. The Cu(II) complexes showed better activity than corresponding Schiff bases.     

Synthesis,crystal structure,and urease inhibition studies of copper(II) and cobalt(III) complexes with bi(2-fluorobenzylaminoethyl)amine

Three new mononuclear Cu(II) and Co(III) complexes [Cu(L)Cl]ClO₄ (1), [Cu(L)Cl(SCN)] (2), and [Co(L)(N₃)₃] (3), where L is a reduced Schiff-base ligand bi(2-fluorobenzylaminoethyl)amine, were synthesized and characterized. X-ray crystallographical analysis reveals that the Cu(II) atom adopts a square-planar environment in complex 1, while the geometry in 2 can be described as distorted square-pyramidal. The Co(III) atom in 3 is in a distorted octahedral geometry. Three complexes were investigated for their inhibitory activities in vitro against jack bean urease. The Cu(II) complexes 1 and 2 were found to have excellent inhibitory activities. The Co(III) complex 3 was also shown to have activity comparable to that of acetohydroxamic acid.     

Two 2-D copper(II) azido compounds: catena -poly[ di -μ1,1- azido,di -μN,O-(quinolinecarboxylato)(aqua)copper(II)] and 1-D catena -poly[ di -μN,N′-(quinoxaline)copper(II)nitrate]

We synthesized three copper(II) complexes with two structurally related polydentate ligands, quinoline-4-carboxylic acid (quCOOH) and quinoxaline (qux). The structures of these complexes were determined using X-ray single crystal crystallography. Complex 1, [Cu(quCOO)(N₃)(H₂O)] _n , has a 2-D polymeric structure through di-μ_1,1 azido groups forming (Cu₂N₂) dimeric units and di-μ_N,O quinoline carboxylate bridging the binuclear copper units. [Cu(quCOO)(N₃)(H₂O)] _n · 0.87MeOH, (2), has the same structure as 1 in addition to MeOH molecules separating the 2-D sheets of [Cu(quCOO)(N₃)(H₂O)] _n . [Cu(qux)(NO₃)₂] _n , (3), has no coordinated azido groups, but the quinoxaline is a bidentate bridging ligand giving a 1-D chain, while the μ_O,O′ chelating nitrato groups stabilize the chain structure by forming a square planar coordination sphere around copper. IR and UV–Vis spectra of the complexes are in agreement with the crystal structures.     

以螺吡喃衍生物原位合成的席夫碱配体的铜配合物的制备及表征

在Cu2+存在条件下,利用N-羟乙基-3,3-二甲基-6-硝基吲哚啉螺吡喃分别与乙二胺分子或1,3-丙二胺分子(1,3-diamino-propane,1,3-DAP)发生原位反应,得到了席夫碱配体双-((2-(甲基亚胺甲基)-4-硝基苯酚))阴离子(L1)或2-((3-胺基丙基亚胺)-甲基)-4-硝基苯酚阴离子(L2...     

Binary and ternary oxorhenium(V) complexes: synthesis,characterization, and crystal structure

A series of anionic five-coordinate binary oxorhenium(V) complexes with dithiolato ligands, Bu₄N[ReO(L¹)₂] (1a), Bu₄N[ReO(L²)₂] (1b), and Bu₄N[ReO(L³)₂] (1c), and a series of neutral octahedral ternary oxorhenium(V) complexes of mixed dithiolato and bipyridine ligands, [ReO(L¹)(bpy)Cl] (2a), [ReO(L²)(bpy)Cl] (2b), and [ReO(L³)(bpy)Cl] (2c) (where L¹H₂ = ethane-1,2-dithiol, L²H₂ = propane-1,3-dithiol, L³H₂ = toluene-3,4-dithiol, and bpy = 2,2′-bipyridine), were isolated and characterized by physicochemical and spectroscopic methods. The solid state structure of 1c was established by X-ray crystallography. All the mononuclear oxorhenium(V) complexes are diamagnetic. The redox behavior of all the complexes has been studied voltammetrically.     

Copper(I) and copper(II) complexes with pyrazine-containing pyridylalkylamide ligands N-(pyridin-2-ylmethyl)pyrazine-2-carboxamide and N-(2-(pyridin-2-yl)ethyl)pyrazine-2-carboxamide

Four copper(II) complexes and one copper(I) complex with pyridine-containing pyridylalkylamide ligands N-(pyridin-2-ylmethyl)pyrazine-2-carboxamide (HL^pz) and N-(2-(pyridin-2-yl)ethyl)pyrazine-2-carboxamide (HL^pz?) were synthesized and characterized. The X-ray crystal structures of [Cu₂(L^pz)₂(4,4?-bipy)(OTf)₂] (1, OTf?=?trifluoromethanesulfonate, 4,4?-bipy?=?4,4?-bipyridine) and [Cu(L^pz)(py)₂]OTf·H₂O (2, py?=?pyridine) revealed binuclear and mononuclear molecular species, respectively, while [Cu(L^pz)(μ₂-1,1-N₃)]_n (3), [Cu(L^pz?)(μ₂-1,3-N₃)]_n (4), and [Cu(HL^pz)Cl]_n (5) are coordination polymer 1-D chains in the solid state.     

Macrocyclic effects upon isomeric CuIIMII and MIICuII cores. Formation with unsymmetric phenol-based macrocyclic ligands

This paper discusses coordination-position isomeric M^IICu^II and Cu^IIM^II complexes, using unsymmetric dinucleating macrocycles (L^m;n)²⁻ ((L^2;2)²⁻, (L^2;3)²⁻ and (L^2;4)²⁻) that comprise two 2-(N-methyl)-aminomethyl-6-iminomethyl-4-bromo-phenonate entities, combined through the ethylene chain (m = 2) between the two amine nitrogens and through the ethylene, trimethylene or tetramethylene chain(n = 2, 3 or 4) between the two imine nitrogens. The macrocycles have dissimilar N(amine)₂O₂ and N(imine)₂O₂ metal-binding sites sharing the phenolic oxygens. The reaction of the mononuclear Cu^II precursors, [Cu(L^2;2)], [Cu(L^2;2)] and [Cu(L^2;2)], with a M^II perchlorate and a M^II acetate salt formed (acetato)M^IICu^II complexes: [CoCu(L^2;2)(AcO)]ClO⁴·0.5H₂O] (1), [NiCu(L^2;2) (AcO)]ClO₄ (2), [ZnCu(L^2;2) (AcO)]ClO₄ (3), [CoCu(L^2;3)(AcO)]ClO₄·0.5H₂O (4), [NiCu(L^2;3)(AcO)]ClO₄ (5), [ZnCu(L^2;3)(AcO)]ClO₄·0.5H₂O (6), [CoCu(L^2;4)(AcO)(DMF)]ClO₄ (7), [NiCu(L^2;4) (AcO)]ClO₄·2DMF (8) and [ZnCu(L^2;4)(AcO)]ClO₄ (9) (the formulation [M_aM_b (L^m;n)]²⁺ means that M_a resides in the aminic site and M_b in the iminic site). The site selectivity of the metal ions is demonstrated by X-ray crystallographic studies for 2·MeOH,3,5,7, and9. An (acetato)Cu^IIZn^II complex, [CuZn(L^2;3)(AcO)]ClO₄ (10), was obtained by the reaction of [PbCu(L^2;3)]-(ClO₄)₂ with ZnSO₄·4H₂O, in the presence of sodium acetate. Other complexes of the Cu^IIM^II type were thermodynamically unstable to cause a scrambling of metal ions. The Cu migration from the iminic site to the aminic site in the synthesis of10 is explained by the ‘kinetic macrocyclic effect’. The coordination-position isomers,6 and10, are differentiated by physicochemical properties.     

Crystal structures,electrochemical properties,antioxidant screening and in vitro cytotoxic studies on four novel Cu(II) complexes of bidentate Schiff base ligands derived from 2-methoxyethylamine

Four novel Schiff base ligands and their copper(II) complexes, [Cu(L¹)₂] (1), [Cu(L²)₂] (2), [Cu(L³)₂] (3), and [Cu(L⁴)₂] (4), were synthesized and characterized by elemental analyses, FT-IR, and UV–Vis spectroscopy. The ligands were synthesized from the condensation of 2-methoxyethylamine with various salicylaldehyde derivatives (x-salicylaldehyde for HLⁿ, x = H (n = 1), 5-Br (n = 2), 3-OMe (n = 3), and 4-OMe (n = 4)). The molecular structures of 1, 2, and 3 were determined by the single crystal X-ray diffraction technique. The redox behavior studies of the complexes in acetonitrile display the electronic effects of the groups on the redox potential. The antioxidant activity of the Schiff base ligands and their Cu(II) complexes was evaluated using the 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging method and FRAP assay. Furthermore, the in vitro anticancer activity of compounds was screened, including MTT and migration assays against gastric cancer cell line (MKN-45). The results show that all ligands and complexes have antioxidant and anticancer activity in a concentration-dependent way.     

Dinuclear Schiff-base copper(II) complexes with various bridging groups

Three new centrosymmetric dinuclear copper(II) complexes, [Cu₂Cl₂(L¹)₂] (1), [Cu₂(μ _1,3-NCS)₂(L²)₂] (2), and [Cu₂(μ _1,1-N₃)₂(L³)₂] (3), where L¹, L², and L³ are the deprotonated forms of the Schiff bases 1-[(2-propylaminoethylimino)methyl]naphthalen-2-ol (HL¹), 1-[(3-methylaminopropylimino)methyl]naphthalen-2-ol (HL²), and 2-[(2-isopropylaminoethylimino)methyl]phenol (HL³), respectively, have been prepared and characterized by elemental analysis, IR spectra, and single-crystal X-ray crystallography. Each Cu is coordinated by the three donors of the Schiff bases and by two bridging groups, forming a square-pyramidal geometry.     

Variation in crystalline architectures through supramolecular interactions in copper(II) complexes with tridentate N2O donor Schiff bases

Three copper(II) complexes, [Cu(L¹)(H₂O)(ClO₄)]·0.5H₂O (1), [Cu(L²)(H₂O)(ClO₄)]·0.5H₂O (2), and [Cu(L²)(NCNC(OCH₃)NH₂)]ClO₄ (3), where HL¹ = 4-bromo-2-(-(quinolin-8-ylimino)methyl)phenol and HL² = 1-(-(quinolin-8-ylimino)methyl)naphthalen-2-ol, have been prepared and characterized by elemental analysis, IR, UV–vis and fluorescence spectroscopy and single-crystal X-ray diffraction studies. The copper(II) centers assume five-coordinate square-pyramidal geometries in 1 and 2, whereas square planar copper(II) is present in 3. A methanol molecule has been inserted in the pendant end of the ligated dicyanamide in 3. Various supramolecular architectures are formed by hydrogen bonding, π?π, C–H?π, and lp?π interactions.     

Three new coordination complexes of cobalt(III), manganese(II), and copper(II) with N,N,O-donor hydrazone ligands: syntheses and structural characterizations

Three new coordination complexes, 2{[Co(L¹)₂]ClO₄} · 0.5CH₃OH (1), [Mn(L²)₂] (2), and [Cu(HL²)(L²)]ClO₄ · 2H₂O (3) have been synthesized from two tridentate N,N,O-donor hydrazone ligands HL¹, 2-acetylpyridine-salicyloylhydrazone, and HL², 2-benzoylpyridine-salicyloylhydrazone, respectively and thoroughly characterized by elemental analysis, FT-IR, UV–Vis, electrochemical, and room temperature magnetic susceptibility measurements. Structures of the complexes have been unequivocally established by single crystal X-ray diffraction technique. Structural analysis reveals that 1 consists of two chemically similar but crystallographically independent cationic [Co(L¹)₂]⁺ units and 2 consists of a neutral [Mn(L²)₂] molecule while 3 consists of a cationic [Cu(HL²)(L²)]⁺ unit. Metal ions display distorted octahedral geometry in 1 and 2 while in 3 it shows a distorted square pyramidal geometry. Ligand conformations around the metal ions are stabilized by the presence of intra-ligand hydrogen bonding in all the complexes. Structure of 3 reveals that a perchlorate ion linked to the complex by hydrogen bonding via a water molecule.     

Heteronuclear complexes of oxorhenium(V) with Fe(III), Co(II), Ni(II), Cu(II), Cd(II) and UO2(VI) and their biological activities

Heteronuclear complexes containing oxorhenium(V), with Fe(III), Co(II), Ni(II), Cu(II), Cd(II) and UO₂(VI) ions were prepared by the reaction of the complex ligands [ReO(HL¹)(PPh₃)(OH₂)Cl]Cl (a) and/or [ReO(H₂L²)(PPh₃)(OH₂)Cl]Cl (b), where H₂L¹?=?1-(2-hydroxyphenyl)butane-1,3-dione-3-(5,6-diphenyl-1,2,4-triazine-3-ylhydrazone) and H₃L²?=?1-(2-hydroxyphenyl)butane-1,3-dione-3-(1H-benzimidazol-2-ylhydrazone), with transition and actinide salts. Heterodinuclear complexes of ReO(V) with Fe(III), Co(II), Ni(II), Cu(II) and Cd(II) were obtained using a 1?:?1 mole ratio of the complex ligand and the metal salt. Heterotrinuclear complexes were obtained containing ReO(V) with UO₂(VI) and Cu(II) using 2?:?1 mole ratios of the complex ligand and the metal salts. The complex ligands a and b coordinate with the heterometal ion via a nitrogen of the heterocyclic ring and the nitrogen atom of the C=N⁷ group. All transition metal cations in the heteronuclear complexes have octahedral configurations, while UO₂(VI)?complexes have distorted dodecahedral geometry. The structures of the complexes were elucidated by IR, ESR, electronic and ¹H NMR spectra, magnetic moments, conductance and TG-DSC measurements. The antifungal activities of the complex ligands and their heteronuclear complexes towards Alternaria alternata and Aspergillus niger showed comparable behavior with some well-known antibiotics.     

Copper(II) complexes of thiazolylazo dye with triphenylphosphine and or NCS− as coligands: synthesis,spectral characterization,electrochemistry and luminescence properties

A series of copper(II) complexes [Cu(L₁ or L₂ or L₃)(PPh₃)₂(N₃)₂] (1a–3a) and [Cu(L₁ or L₂ or L₃)(PPh₃)₂(NCS)₂] (1b–3b) (where L₁ = 4-(4′-phenyl,2′-thiazolylazo)chlorobenzene, L₂ = 4-(4′-phenyl,2′-thiazolylazo)bromobenzene, and L₃ = 4-(4′-phenyl,2′-thiazolylazo)iodobenzene) have been prepared and characterized on the basis of microanalytical data, molar conductances, magnetic moments, UV-Vis, infrared, and ESR spectra. On the basis of electronic spectra and magnetic susceptibility octahedral geometry has been proposed for the complexes. The ESR spectral data provide information about their structures on the basis of Hamiltonian parameters and degree of covalancy. The electrochemical behavior of the complexes showed that the redox responses of Cu(II) complexes shifted to more negative potential with decrease in electron-withdrawing substituents on the azo ligands. Complexes exhibit blue-green emission with high-quantum yield.     

Synthesis,crystal structures and biological evaluation of three ternary copper(II) complexes with fluorinated anthranilic acid derivatives

Three ternary copper(II) complexes [Cu(L¹)(phen)] (1), [Cu(L²)(phen)] (2), and [Cu(L³)(phen)]·2H₂O (3) (L¹ = 4-fluoro-2-(picolinamido)benzoic acid, L² = 4,5-difluoro-2-(picolinamido)benzoic acid, L³ = 4,5-difluoro-2-((2-hydroxybenzylidene)amino)benzoic acid, phen = 1,10-phenanthroline) have been synthesized and characterized by physicochemical and spectroscopic methods. In addition, X-ray crystallography showed that the Cu atoms in each of the complexes are five-coordinate, adopting distorted square pyramidal or trigonal bipyramidal geometries. The interactions of the complexes with calf-thymus DNA were investigated by UV absorption, fluorescence spectroscopy and viscosity measurements. In addition, the complexes were screened for in vitro cytotoxicity against A549 (human pulmonary carcinoma cells), Jurkat (human T lymphocyte cell line) and HepG-2 (human liver hepatocellular carcinoma cells); these experiments showed that complex 3 exhibited the most effective cytotoxicities (IC₅₀ = 1.224–7.099 µM). Antibacterial studies revealed that complex 3 also exhibited highest activity, consistent with the DNA binding affinities.     

Synthesis,crystal structures,spectroscopic studies and antibacterial properties of a series of mononuclear cobalt(III) Schiff base complexes

New complexes of cobalt(III) with the tridentate and tetradentate Schiff base ligands: 3-methoxy-2-{(Z)[(2-hydroxyphenyl)imino]methyl}phenol (H₂L¹), 4-[(2-hydroxyphenyl)imino]-2-pentanone (H₂L²); and 2-((E)-1-(2-((E)-1-(2-hydroxy-4,5-dimethylphenyl)ethylideneamino)ethylimino)ethyl)-4,5 dimethylphenol (H₂L³), namely [Co^III(L¹)(N-MeIm)₃]PF₆ (1), [Co^III(L¹)(py)₃]ClO₄ (2), [Co(L¹)(py)₃][Co(L¹)₂] (3) and [Co^III(L²)(N-MeIm)₃]PF₆ (4) and [Co(L³)(N-MeIm)₂]PF₆ (5), were synthesized and characterized by physico-chemical and spectroscopic methods. The crystal structures of the complexes were determined by X-ray crystallography. In each of these complexes, the cobalt(III) centre has a slightly distorted octahedral environment, utilizing all available coordination centres of the ligands. The complexes were also screened for in vitro antibacterial activities against four human pathogenic bacteria, and their minimum inhibitory concentrations indicated good antibacterial activities.