共查询到20条相似文献,搜索用时 46 毫秒
1.
J.-Pablo Salvador Francisco Sánchez-Baeza M.-Pilar Marco 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2010,878(2):243-252
A high-throughput immunosorbent solid-phase extraction (HTS-IS-SPE) procedure coupled to enzyme-linked immunosorbent assay (ELISA) has been established for the analysis of stanozolol (St) and its main metabolite in cattle, 16β-hydroxy-stanozolol (16βOH-St), in cow urine samples. The chemical structure of the immunizing hapten 2′H-androst-2-eno[3,2-c]-pyrazol-17-hemiglutarate 5 (hapten A) has been designed to accomplish simultaneous detection of St and 16βOH-St. The antibodies obtained have been used to establish a microplate ELISA method able to detect these metabolites with IC50 values of 0.57 μg L−1 and 1.46 μg L−1, respectively in PBST. Immunosorbents prepared by covalently attaching the antibodies to Sepharose, efficiently removed the matrix interferences caused by the cattle urine samples. Moreover, St and 16βOH-St were efficiently extracted from urine samples as demonstrated by LC–MS/MS analysis. The immunosorbents are filled on small mini-columns arranges on a 96-SPE-setup compatible with the microplate based ELISA methods. Samples and standards can be run in parallel which increment considerably the speed of the screening method. The recovery values of the whole HTS-IS-SPE-ELISA procedure has found to be 112 ± 10% and St can be detected in hydrolyzed urine samples with LOD of 1.26 ± 0.46 μg L−1 using just 1 mL of sample. As proof-of-concept the urinary excretion profile of St treated animals has been investigated by analyzing individual sampling points. Results from pooled urine samples have also been compared with the results obtained by GC–MS analysis demonstrating the StIR equiv. measured with the HTS-IS-SPE-ELISA protocol are in accordance with the St and 16βOH-St levels found with the chromatographic method. The analytical procedure is rapid, effective and the detectability achieved is below the MPRL (minimum performance required levels) recommended by CRL (Community Reference Laboratory) to the European Community. 相似文献
2.
Rongqing Li Pusu Zhao Yulan Zhu Weiguang Zhang Hongyan Wang 《Inorganica chimica acta》2009,362(11):4081-3393
Oxalate- or 4,4′-bipyridine-bridged dimeric copper(II) complexes, [Cu2L2(μ-ox)] (1) and [Cu2L2(μ-bipy)](BF4)2 (2) [where ox = oxalate, bipy = 4,4′-bipyridine, HL = N-(1H-pyrrol-2-ylmethylene)-2-pyridineethanamine, L− = HL−H+], have been synthesised and characterised by elemental analysis, IR, UV-Vis and single crystal X-ray diffraction. Crystal structure determinations carried out on 1 and 2 reveal that 1 is an oxalate-bridged centrosymmetrical square pyramidal dimeric copper(II) complex while 2 is a 4,4′-bipyridine-bridged non-centrosymmetric square planar dinuclear copper(II) complex. Comparison of the optimised geometries with the corresponding crystal structures suggests that the B3LYP/LANL2DZ level can reproduce the structures of 1 and 2 on the whole. The electronic spectra of 1 and 2 predicted by B3LYP/LANL2DZ method show some blue shifts compared with their experimental data. Thermal analysis carried out on 1 shows that there is only one exothermal peak at about 260 °C and the residue is presumably Cu2O4N6. 相似文献
3.
Six new transition metal complexes (M = Cu(II), Ni(II) and Mn(III)) of tridentate (H2L1, HL2) and/or bidentate (HL3, HL4) Schiff-base ligands, obtained from the condensation of salicylaldehyde with glycine, N-(2-aminoethyl)morpholine, 4-(2-aminoethyl)phenylic acid and 4-(2-aminoethyl)benzsulfamide, respectively, were synthesized and structurally determined by single-crystal X-ray analysis. Complexes 1-6 were evaluated for their effect on the jack bean urease and xanthine oxidase (XO). Copper(II) complexes 1-3 (IC50 = 0.43-2.25 μM) showed potent inhibitory activity against jack bean urease, comparable with acetohydroxamicacid (IC50 = 42.12 μM), which is a positive reference. And these copper(II) complexes (IC50 = 10.26-15.82 μM) also exhibited strong ability to inhibit activity of XO, comparable to allopurinol (IC50 = 10.37 μM), which was used as a positive reference. Nickel(II) and manganese(III) complexes 4-6 showed weak inhibitory activity to jack bean urease (IC50 = 4.36-8.25 μM) and no ability to inhibit XO (IC50 > 100 μM). 相似文献
4.
Lahiri D Majumdar R Mallick D Goswami TK Dighe RR Chakravarty AR 《Journal of inorganic biochemistry》2011,105(8):1086-1094
Copper(II) complexes [Cu(satp)(L)] (1-3) of a Schiff base thiolate (salicylidene-2-aminothiophenol, H2satp) and phenanthroline bases (L), viz. 1,10-phenanthroline (phen in 1), dipyrido[3,2-d:2′,3′-f]quinoxaline (dpq in 2) and dipyrido[3,2-a:2′,3′-c]phenazine (dppz in 3), were prepared, characterized and their anaerobic DNA photocleavage activity and hypoxic photocytotoxicity studied. The redox active complexes show the Cu(II)-Cu(I) couple near − 0.5 V for 1 and near 0.0 V vs. SCE (saturated calomel electrode) for 2 and 3. The one-electron paramagnetic complexes (~ 1.85 μB) are avid DNA binders giving Kb values within 1.0 × 105 − 8.0 × 105 M− 1. Thermal melting and viscosity data along with molecular docking calculations suggest DNA groove and/or partial intercalative binding of the complexes. The complexes show anaerobic DNA cleavage activity in red light under argon via type-I pathway, while DNA photocleavage in air proceeds via hydroxyl radical pathway. The DFT (density functional theory) calculations reveal a thyil radical pathway for the anaerobic DNA photocleavage activity and suggest the possibility of generation of a transient copper(I) species due to bond breakage between the copper and sulfur to generate the thyil radical. An oxidation of the copper(I) species is likely by oxygen in an aerobic medium or by the buffer medium in an anaerobic condition. Complex 3 exhibits significant photocytotoxicity in HeLa cells (IC50 = 8.3(± 1.0) μM) in visible light, while showing lower dark toxicity (IC50 = 17.2(± 1.0) μM). A significant reduction in the dark toxicity is observed under hypoxic cellular conditions (IC50 = 30.0(± 1.0) μM in dark), while retaining its photocytotoxicity (IC50 = 8.0(± 1.0) μM). 相似文献
5.
Katerina N. Lazarou 《Inorganica chimica acta》2011,370(1):50-58
The reactions of salicylaldehyde oxime (H2salox) with CuII precursors yielded the known complexes [Cu(Hsalox)2] (1) and [Cu(Hsalox)2]n (2), as well as complexes [Cu3(salox)(L1)(L2)]·MeCN (3·MeCN), [CuCl(L1)] (4) and [Cu2Na(O2CMe)5(HO2CMe)]n (5), where L1− = o-O-C6H4-CHNO-C(CH3)NH and L23− = o-O-C6H4-CHNO-C(o-O-C6H4)N. L1− was formed in situ via the nucleophilic addition of the oximato O-atom of salox2− to the unsaturated nitrile group of the MeCN reaction solvent. L23− is also formed in situ probably through the nucleophilic attack of the oximato O-atom to the unsaturated nitrile group of salicylnitrile; the latter, although not directly added to the reaction mixture, can be produced via the dehydration of salox2−. Compounds 1 and 2 contain Hsalox− bound to the metal center in two different coordination modes; they both contain the same mononuclear unit, however a 2D network is generated in 2 due to a relatively long Cu-Ooximato bond. Compound 3 contains three different ligands, i.e. salox2−, L1− and L23−, which act as μ3-κ2O:κO′:κN, κO:κN:κN′ and μ3-κ2O:κ2N:κO′:κN′, respectively, whereas 4 consists of a square planar CuII atom bound to a κO:κN:κN′ L1− and a chloride ion. Compound 5 consists of dinuclear [Cu2(O2CMe)5(HO2CMe)]− units and Na+ ions assembled into an overall 3D network structure. Magnetic susceptibility measurements from polycrystalline samples of 2 and 5 gave best-fit parameters J = +0.36 cm−1 (H = −J?i?j) and J = −360 cm−1, zj = +20 cm−1 (H = −J?i?j − zJ〈Sz〉?z), respectively. 相似文献
6.
Shyamapada Shit Corrado Rizzoli Guillaume Pilet Samiran Mitra 《Inorganica chimica acta》2011,370(1):18-26
Three new Cu(II) complexes of formula [Cu(L1)(pyz)(CH3OH)]ClO4 (1), [Cu(L1)(4,4′-bpy)(ClO4)]·0.5H2O (2) and [{Cu(L2)(ClO4)}2(μ-4,4′-bpy)] (3) have been synthesised by using pyrazine (pyz) and 4,4′-bipyridine (4,4′-bpy) and tridentate O,N,O-donor hydrazone ligands, L1H and L2H, obtained by the condensation of 1,1,1-trifluoro-2,4-pentanedione with salicyloylhydrazide and benzhydrazide, respectively. The ligands and their complexes have been characterized by elemental analyses, FT-IR, and UV-Vis spectroscopies. Single crystal X-ray structure analysis evidences the metal ion in a slightly deformed square pyramidal geometry in all the complexes. However complexes 1 and 2 are mononuclear with pyz and 4,4′-bpy, respectively, showing an unusual monodentate behavior, while complex 3 is dinuclear with 4,4′-bpy adopting the typical bridging coordination mode. Self assembly of the complex units by hydrogen bonding interactions produces one-dimensional arrangement in each crystal packing. The magnetic characterization of complex 3 indicates a weak antiferromagnetic exchange interaction between the Cu(II) ions (J = −0.96 cm−1) mediated through the long 4,4′-bpy bridge. Electrochemical behavior of the complexes is also discussed. 相似文献
7.
Three kinds of copper(II) azide complexes have been synthesised in excellent yields by reacting Cu(ClO4)2 · 6H2O with N,N-bis(2-pyridylmethyl)amine (L1); N-(2-pyridylmethyl)-N′,N′-dimethylethylenediamine (L2); and N-(2-pyridylmethyl)-N′,N′-diethylethylenediamine (L3), respectively, in the presence of slight excess of sodium azide. They are the monomeric Cu(L1)(N3)(ClO4) (1), the end-to-end diazido-bridged Cu2(L2)2(μ-1,3-N3)2(ClO4)2 (2) and the single azido-bridged (μ-1,3-) 1D chain [Cu(L3)(μ-1,3-N3)]n(ClO4)n (3). The crystal and molecular structures of these complexes have been solved. The variable temperature magnetic moments of type 2 and type 3 complexes were studied. Temperature dependent susceptibility for 2 was fitted using the Bleaney-Bowers expression which led to the parameters J = −3.43 cm−1 and R = 1 × 10−5. The magnetic data for 3 were fitted to Baker’s expression for S = 1/2 and the parameters obtained were J = 1.6 cm−1 and R = 3.2 × 10−4. Crystal data are as follows. Cu(L1)(N3)(ClO4): Chemical formula, C12H13ClN6O4Cu; crystal system, monoclinic; space group, P21/c; a = 8.788(12), b = 13.045(15), c = 14.213(15) Å; β = 102.960(10)°; Z = 4. Cu(L2)(μ-N3)(ClO4): Chemical formula, C10H17ClN6O4Cu: crystal system, monoclinic; space group, P21/c; a = 10.790(12), b = 8.568(9), c = 16.651(17) Å; β = 102.360(10)°; Z = 4. [Cu(L3)(μ-N3)](ClO4): Chemical formula, C12H21ClN6O4Cu; crystal system, monoclinic; space group, P21/c; a = 12.331(14), b = 7.804(9), c = 18.64(2) Å; β = 103.405(10)°; Z = 4. 相似文献
8.
Zdeněk Trávní?ek Igor Popa Radek Zbo?il Ji?í Mikulík 《Journal of inorganic biochemistry》2010,104(4):405-11728
The first FeIII complexes 1-6 with cyclin-dependent kinase (CDK) inhibitors of the type [Fe(Ln)Cl3]·nH2O (n = 0 for 1, 1 for 2, 2 for 3-6; L1-L6 = C2- and phenyl-substituted CDK inhibitors derived from 6-benzylamino-9-isopropylpurine), have been synthesized and characterized by elemental analysis, IR, 57Fe Mössbauer, 1H and 13C NMR, and ES+ mass spectroscopies, conductivity and magnetic susceptibility measurements, and thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). The study revealed that the compounds are mononuclear, tetrahedral high-spin (S = 5/2) FeIII complexes with an admixture of an S = 3/2 spin state originating probably from five-coordinated FeIII ions either connecting with a bidentate coordination mode of the CDK inhibitor ligand or relating to the possibility that one crystal water molecule enters the coordination sphere of the central atom in a portion of molecules of the appropriate complex. Nearly spin-only value of the effective magnetic moment (5.82 μeff/μB) was determined for compound 1 due to absence of crystal water molecule(s) in the structure of the complex. Based on NMR data and DFT calculations, we assume that the appropriate organic ligand is coordinated to the FeIII ion through the N7 atom of a purine moiety. The cytotoxicity of the complexes was tested in vitro against selected human cancer cell lines (G-361, HOS, K-562 and MCF-7) along with the ability to inhibit the CDK2/cyclinE kinase. The best cytotoxicity (IC50: 4-23 μM) and inhibition activity (IC50: 0.02-0.09 μM) results have been achieved in the case of complexes 2-4, and complexes 3, 4 and 6, respectively. In addition, the X-ray structure of 2-chloro-6-benzylamino-9-isopropylpurine, i.e. a precursor for the preparation of L1, L4 and L5, is also described. 相似文献
9.
Oxovanadium(IV) complexes [VO(L)(B)] (1-3), where H2L is a Schiff base ligand 2-(2-hydroxybenzylideneamino)phenol and B is 1,10-phenanthroline (phen for 1), dipyrido[3,2-d:2′,3′-f]quinoxaline (dpq for 2) or dipyrido[3,2-a:2′,3′-c]phenazine (dppz for 3), have been prepared, characterized and their DNA binding property and photo-induced DNA cleavage activity studied. Complex 3 which is structurally characterized by X-ray crystallography shows the presence of an oxovanadium(IV) moiety in a six coordinate VO3N3 coordination geometry. The complexes show a d-d band within 800-850 nm in DMF. The complexes display an oxidative response near 0.7 V versus SCE for V(V)-V(IV) and a reductive response within −1.1 to −1.3 V due to V(IV)-V(III) couple in DMF-0.1 M TBAP. The complexes are avid binders to calf thymus DNA giving binding constant values of 4.2 × 104 to 1.2 × 105 M−1. The complexes do not show any “chemical nuclease” activity in dark. The dpq and dppz complexes are photocleavers of plasmid DNA in UV-A light of 365 nm via 1O2 pathway and in near-IR light (752.5 to 799.3 nm IR optics) by HO• pathway. Complex 3 exhibits significant photocytotoxicity in visible light in HeLa cells giving IC50 value of 13 μM, while it is less toxic in dark (IC50 = 97 μM). 相似文献
10.
The DNA binding and in vitro cytotoxicity of the dinuclear Ir(III) polypyridyl complexes [{(η5-C5Me5)Ir(dppz)}2(μ-pyz)](CF3SO3)41 and [{(η5-C5Me5)Ir(pp)}2(μ-4,4′-bpy)](CF3SO3)42-4 (pp = dipyrido[3,2-d:2′,3′-f]quinoxaline (dpq), dipyrido[2,3-a:2′,3′-c]phenazine (dppz), benzo[i]dipyrido[3,2-a:2′,3′-c]phenazine (dppn)) with the rigid bridging ligands pyrazine (pyz) or 4,4′-bipyridine (4,4′-bpy) have been studied. Stable intercalative binding into CT DNA (calf thymus DNA) is indicated for the dppz complexes 1 and 3 by induced negative CD bands at about 300 nm and large viscosity increases, with the individual measurements being in accordance with intrastrand bis-intercalation for 3 and mono-intercalation for 1. The observed interruption of specific interresidue NOE cross peaks from the relevant nucleobase H6/H8 protons to the sugar H2′/H2″ protons of the preceding nucleotide is in accordance with bis-intercalation of complex 3 between the C3G18 and G4C17 base pairs and the T5A16 and A6T15 base pairs of the decanucleotide d(5′-CGCGTAGGCC-3′). Complexes 1 and 3 exhibit a greatly improved uptake by HT-29 (colon carcinoma) cells and significantly improved in vitro IC50 values of 1.8 ± 0.1 and 3.8 ± 0.1 μM towards this cell line in comparison to the mononuclear complex [(η5-C5Me5)IrCl(dppz)](CF3SO3) (IC50 = 7.4 ± 0.9 μM). 相似文献
11.
M. Carla Aragoni Francesco Demartin Alessandra Garau Vito Lippolis Silvia Rizzato 《Inorganica chimica acta》2004,357(12):3803-3809
The compounds [Ni(L)(MeCN)]I8 (1) and [Ni(L)(MeCN)]I12 (2) have been obtained from the reactions of the complexes [Ni(L)(L′)][BF4](2 + n) {L=2,5,8-trithia[9](2,9)-1,10-phenanthrolinophane; L′=MeCN, Cl−, Br−, I−; n=charge of L′} with an excess of I2 (molar ratios of 6, 10 and 20 have been used), in the presence of the stoichiometric amount of I− (as Bu4nNI) necessary to balance the charge of the complex cation [Ni(L)(L′)](2 + n)+. An X-ray diffraction analysis shows that, independently of the nature of L′, both 1 and 2 contain the complex cation [Ni(L)(MeCN)]2+, which is therefore capable of templating two different polyiodide networks based on interacting I3−/I5− and I5−/I7 units, respectively. The solid state FT-Raman spectra of 1 and 2 are discussed based on their structural features. 相似文献
12.
A dicyanamide bridged 2D polynuclear complex of copper(II) having molecular formula [Cu2(L)(μ1,5-dca)2]n (1) has been synthesized using the Schiff base ligand N,N′-bis(salicylidene)-1,3-diaminopentane, (H2L) and sodium dicyanamide (dca). The complex presents a 2D hexagonal structure formed by 1,5-dca singly bridged helical chains connected through double 1,5-dca bridges. The chelating characteristics of the H2L Schiff base ligand results in the formation of copper(II) dimer with a double phenoxo bridge presenting a very strong antiferromagnetic coupling in the copper(II) derivative (1) (J = −510 cm−1). The dimeric asymmetric unit of 1 is very similar to the active site of the catechol oxidase and, as expected, also presents catalytic activity for the oxidation of 3,5-di-tert-butylcatechol to 3,5-di-tert-butylquinone in presence of O2, as demonstrated by kinetic studies of this oxidation reaction monitored by absorption spectroscopy resulting in high turnover number (Kcat = 259 h−1). 相似文献
13.
Michael W. Cooke 《Inorganica chimica acta》2008,361(8):2259-2269
We herein describe the synthesis and characterization of a series of homoleptic, Ru(II) complexes bearing peripheral carboxylic acid functionality based upon the novel ligand 4′-(4-carboxyphenyl)-4,4″-di-(tert-butyl)tpy (L1), as well as 4′-(4-carboxyphenyl)tpy (L2) and 4′-(carboxy)tpy (L3) (where tpy = 2,2′: 6′,2″-terpyridine). Inspection of the metal-based oxidations (E1/2 = 1.22-1.42 V) indicates an anodic shift (∼0.2 V) for (L3)2Ru2+ (3b) (E1/2 = 1.40 V) relative to (L2)2Ru2+ (2b) (E1/2 = 1.22 V). The metal-based oxidation (E1/2 = 1.22 V) and ligand-based reductions (E1/2 = −1.25 to −1.52 V) of (L1)2Ru2+ (1) are essentially invariant relative to those of the structural analogue 2b (PF6)2, which suggests no significant electronic effect caused by the tert-butyl groups. This is supported by invariance in the metal-to-ligand charge transfer bands in both the electronic absorption (494-489 nm) and emission spectra (654-652 nm). However, contrary to 2b, complex 1 is both very soluble and exhibits a highly porous solid-state structure with internal cavity dimensions of 15 Å × 14 Å due to the preclusion of inter-annular interactions by the bulky tert-butyl substituents. 相似文献
14.
Gabriella Tamasi Agnese Magnani Luisa Chiasserini Chiara Gabbiani Michael A. Jakupec Michael B. Hursthouse 《Journal of inorganic biochemistry》2010,104(8):799-313
The reaction of aqueous cis-[Pt(NH3)2(H2O)2](NO3)2 with Na+HMEL− (H2MEL, meloxicam, 4-hydroxy-2-methyl-N-(5-methyl-1,3-thiazol-2-yl)-2H-1,2-benzothiazine-3-carboxamide-1,1-dioxide), and Na+HISO− (H2ISO, isoxicam, 4-hydroxy-2-methyl-N-(5-methylisoxazol-3-yl)-2H-1,2-benzothiazine-3-carboxamide-1,1-dioxide) at pH 7 produced micro-crystalline cis-[Pt(NH3)2(N1′-HMEL)2], 5 and cis-[Pt(NH3)2(N1′-HISO)2], 6. The X-ray diffraction structure of 5 shows two HMEL− anions donating through the thiazole nitrogen atoms and adopting a head-to-tail (HT) conformation. The 1H NMR spectrum for 5 from DMSO-d6 shows inertness of the complex up to at least 24 h. Delivery studies for 5 and 6 from vinyl hydrogel based on l-phenylalanine (pH 6.5, 25 °C) show that concentrations of complexes ranging between 2.5 and 5 μM can be reached after a day. Compounds 5 and 6 show strong anti-proliferative effects on CH1 cells (ovarian carcinoma, human) in vitro, IC50 values being 0.60 and 0.37 μM, respectively (0.16 μM for reference, cis-diamminodichloridoplatinum(II), cisplatin). ESI-MS measurements clearly documented that both 5 and 6 form adducts with the three model proteins ubiquitin (UBI), cytochrome c (CYT C) and superoxide dismutase (SOD), the HISO− complex being significantly more effective than the HMEL− one. Density functional methods help in finding rationale for the easiest dissociation of Pt-H2ISO/HISO bonds when compared to the Pt-N1′-H2MEL/N1′-HMEL linkages. 相似文献
15.
The first [Pd(Ln)2(ox)] xH2O oxalato(ox) complexes involving 2-chloro-N6-(benzyl)-9-isopropyladenine (L1; complex 1), 2-chloro-N6-(4-methoxybenzyl)-9-isopropyladenine (L2; 2), 2-chloro-N6-(2,3-dimethoxybenzyl)-9-isopropyladenine (L3; 3), 2-chloro-N6-(2,4-dimethoxybenzyl)-9-isopropyladenine (L4; 4), and 2-chloro-N6-(4-methylbenzyl)-9-isopropyladenine (L5; 5) have been synthesized by the reactions of potassium bis(oxalato)palladate(II) dihydrate, [K2Pd(ox)2]·2H2O, with the mentioned organic compounds (H2ox = oxalic acid; x = 0 for 1-3 and 5 or 2 for 4). Elemental analyses (C, H, N), FTIR, Raman and NMR (1H, 13C, 15N) spectroscopies, conductivity measurements and thermal studies (thermogravimetric and differential thermal analyses, TG/DTA) have been used to characterize the prepared complexes. The molecular structures of [Pd(L2)2(ox)] (2) and [Pd(L5)2(ox)]·L5·Me2CO (5·L5·Me2CO) have been determined by a single crystal X-ray analysis. The geometry of these complexes is slightly distorted square-planar with two appropriate Ln (n = 2 or 5) molecules mutually arranged in the head-to-head (2) or head-to-tail (5) orientation. The Ln ligands are coordinated to the central Pd(II) ion via the N7 atoms. The same conclusions regarding the binding properties of L1-L5 ligands can be made based on multinuclear NMR spectra. In vitro cytotoxicity of the complexes 1-5 has been evaluated against human chronic myelogenous leukaemia (K562) and human breast adenocarcinoma (MCF7) cancer cell lines. Significant cytotoxicity has been determined for the complexes 3 (IC50 = 6.2 μM) and 5 (IC50 = 6.8 μM) on the MCF7 cell line, which is even better than that found for the well-known and widely-used platinum-bearing antineoplastic drugs, i.e. oxaliplatin and cisplatin. 相似文献
16.
Katsoulakou E Tiliakos M Papaefstathiou G Terzis A Raptopoulou C Geromichalos G Papazisis K Papi R Pantazaki A Kyriakidis D Cordopatis P Manessi-Zoupa E 《Journal of inorganic biochemistry》2008,102(7):1397-1405
Two new organotin(IV) complexes with dianionic dipeptides containing the α-aminoisobutyryl residue (Aib) as ligands are described. The solid complexes [(n-Bu)2Sn(H−1LA)] · 2MeOH (1 · 2MeOH) (LAH = H-Aib-L-Leu-OH) and [(n-Bu)2Sn(H−1LB)] · MeOH (2 · MeOH) (LBH = H-Aib-L-Ala-OH) have been isolated and characterized by single-crystal X-ray crystallography and spectroscopic techniques (H−1L2− is the dianionic form of the corresponding dipeptide). Complexes 1 · 2MeOH and 2 · MeOH are monomeric with similar molecular structures. The doubly deprotonated dipeptide behaves as a N(amino), N(peptide), O(carboxylate) ligand and binds to the SnIV atom. The five-coordinate metal ion has a distorted trigonal bipyramidal geometry. A different network of intermolecular hydrogen bonds in each compound results in very dissimilar supramolecular features. The IR, far-IR, Raman and 119Sn NMR data are discussed in terms of the nature of bonding and known structures. The antibacterial and antiproliferative activities as well as the effect of the new compounds on pDNA were examined. Complexes 1 and 2 are active against the gram-positive bacteria Bacillus subtilis and Bacillus cereus. The IC50 values reveal that the two compounds express promising cytotoxic activity in vitro against a series of cell lines. 相似文献
17.
Leaves and flowers of Artemisia gorgonum (Asteraceae) collected in Fogo, Cape Verde islands, were phytochemically investigated and resulted in isolation and characterization of three guaianolides 1, 2, 5, and a secoguainolide 4, in addition to eight known guaianolides 6-11 and two known germacranolides 12, 13. Structures were elucidated by 1D and 2D NMR experiments. Careful examination of the 13C NMR spectrum led to revision of the structure of a previously described guaianolide from 2 to 3. Most compounds exhibited mild antiplasmodial activities, ridentin (13) being the most interesting with an IC50 of 3.8 ± 0.7 μg ml−1 against Plasmodium falciparum FcB1 and weak cytotoxicity in a vero cell line (IC50 71.0 ± 3.9 μg ml−1). 相似文献
18.
Hiroshi Sakiyama Tetsuya Suzuki Rie Ito Mikio Yamasaki 《Inorganica chimica acta》2005,358(6):1897-1903
Dinuclear nickel(II) complexes [Ni2(bomp)(MeCO2)2]BPh4 (1) and [Ni2(bomp)(PhCO2)2]BPh4 (2) were synthesized with the dinucleating ligand 2,6-bis[bis(2-methoxyethyl)aminomethyl]-4-methylphenol [H(bomp)]. X-Ray analysis revealed that the complex 1 · 0.5CHCl3 contains two nickel(II) ions bridged by phenolic oxygen and two acetate groups, forming a μ-phenoxo-bis(μ-acetato)dinickel(II) core. Electronic spectra were investigated for 1 and 2 in the range of 400-1800 nm, and the data were typical for the octahedral high-spin nickel(II) complexes. Obtained spectral components were well simulated based on the angular overlap model assuming the trigonally distorted octahedral geometry. Magnetic susceptibility was measured for 1 and 2 over a temperature range of 4.5-300 K. The optimized magnetic data were J = 1.75 cm−1, zJ′ = −0.234 cm−1, g = 2.21, D = 15.1 cm−1, and TIP = 370 × 10−6 cm−1 for complex 1 and J = 3.55 cm−1, zJ′ = −0.238 cm−1, g = 2.23, D = 21.8 cm−1, and TIP = 470 × 10−6 cm−1 for complex 2. The data revealed ferromagnetic interactions between the two nickel(II) ions. 相似文献
19.
The Rh(III) polypyridyl complexes of the type [RhCl(pp)([9]aneS3)]2+ [(pp) = 2,2′-bipyridine (bpy), 2,2′-bipyrimidine (bpm),1,10-phenanthroline (phen), pyrazino[2,3-f]quinoxaline (tap), dipyrido[3,2-d:2′,3′-f]quinoxaline (dpq), dipyrido[2,3-a:2′,3′-c]phenazine (dppz)] 2-7 have been prepared in a stepwise manner by treatment of RhCl3 · 3H2O with the appropriate polypyridyl ligand (pp) followed by 1,4,7-trithiacyclononane. Interactions of the polypyridyl complexes with DNA were investigated by CD and UV/visible spectroscopy and by gel electrophoresis. The dpq complex 6 cleaves DNA exiguously in the dark, but UV irradiation is required to induce nuclease activity for the bpy complex 2. Whereas 2 [IC50 values: 12.8 (±0.2) and 4.4 (±0.1) μM] exhibits significantly higher cytotoxicities towards MCF-7 and HT-29 cells than 4 [IC50 values: 36.3 (±6.0) and 72.2 (±8.0)], the activity of complexes in the series 4/6/7 correlates directly with the size of the polypyridyl ligand, as documented by their respective IC50 values of 72.2 (±8.0), 20.9 (±2.8) and 7.4 (±2.2) towards HT-29 cells. Complexes of the nitrogen-rich ligands bpm (3) [IC50 values: 1.7 (±0.5) and 1.9 (±0.1) μM] and tap (5) [IC50 values: 11.5 (±0.6) and 7.6 (±4.8) μM] are considerably more potent than their bpy and phen counterparts 2 and 4. Measurement of the lactate dehydrogenase release for lymphoma (BJAB) cells after 1 h incubation demonstrates that unspecific necrosis is negligible for the most active compounds 3 and 7. Specific cell death apoptosis via DNA fragmentation was detected for BJAB cells after 72 h incubation and significant loss of the mitochondrial membrane potential in lymphoma cells indicates that the intrinsic pathway is involved. 相似文献
20.
R.N. Patel 《Inorganica chimica acta》2010,363(14):3838-3846
Two new binuclear end-on bis(μ-acetato/μ-nitrato) bridged complexes with two NNO donor ligands, viz., [(L1)Cu(μ-CH3COO)2Cu(L1)]·4,4-bipy 1 and [(L2)Cu(μ-NO3)2Cu(L2)] 2 where [L1 = N′-[phenyl(pyridin-2-yl)methylidene]furan-2-carbohydrazide, L2 = (2E,4Z)-N,2-dimethylhepta-2,4,6-trienamide-1-phenyl-1-pyridin-2-ylmethanimine (1:1) μ-CH3COO− = μ-acetato and μ-NO3− = μ-nitrato) have been prepared and physiochemically characterized. These complexes are structurally characterized by X-ray crystallography. In both complexes, the two copper centers are linked by two acetate or two nitrate groups in end-on bonding fashion. The copper-copper separation is 3.279 Å for 1 and 3.459 Å for 2. The copper ions are pentacoordinated in both complexes. The coordination geometry may be described as close to square pyramidal (SP) stereochemistry with slight distortion to trigonal bipyramidal (TBP) stereochemistry. The polycrystalline epr spectra of these two complexes exhibit the properties commensurate with S = 1 systems. The magnetic moment (μeff) for these complexes are below the theoretical value suggesting antiferromagnetic exchange between the copper(II) ions. The cyclic voltammograms (CV) of the two complexes have been investigated. Superoxide dismutase (SOD) activity of these complexes has also been measured. These complexes can catalyze the dismutation of superoxide. 相似文献