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1.
Shahram Khademvatan Neda Adibpour Alborz Eskandari Saeed Rezaee Mahmoud Hashemitabar Fakher Rahim 《Experimental parasitology》2013
This in silico and in vitro comparative study was designed to evaluate the effectiveness of some biurets (K1 to K8) and glucantime against Leishmania major and Leishmania infantum promastigotes. Overall, eight experimental ligands and glucantime were docked using AutoDock 4.3 program into the active sites of Leishmania major and Leishmania infantum pteridine reductase 1, which were modeled using homology modeling programs. The colorimetric MTT assay was used to find L. major and L. infantum promastigotes viability at different concentrations of biuret derivatives in a concentration and time-dependent manner and the obtained results were expressed as 50% and 90% of inhibitory concentration (IC50 and IC90). In silico method showed that out of eight experimental ligands, four compounds were more active on pteridine reductase 1. K3 was the most active against L. major promastigotes with an IC50 of 6.8 μM and an IC90 of 40.2 μM, whereas for L. infantum promastigotes was K8 with IC50 of 7.8 μM. The phenylethyl derivative (K7) showed less toxicity (IC50s > 60 μM) in both Leishmania strains. Glucantime displayed less growth inhibition in concentration of about 20 μM. In silico and especially docking results in a recent study were in accordance with the in vitro activity of these compounds in presented study and compound K3, K2 and K8 showed reasonable levels of selectivity for the Leishmania pteridine reductase 1. 相似文献
2.
Jörg Wagler Erica Brendler Sigrid Goutal Bernhard Kempf Gerhard Roewer 《Inorganica chimica acta》2005,358(14):4270-4286
The reaction between phenyltrichlorosilane and the tetradentate ligands o-HO-C6H4-C(CH3)N-(CH2)n-NC(CH3)-o-C6H4-OH (n = 2, 3, 4), supported by an amine base, yields pentacoordinate silicon complexes (C6H5)Si-[o-O-C6H4-C(CH3)N-(CH2)n-N-C(CH2)-o-C6H4-O] with enamine functionalized ligands. This reaction pattern can be transferred onto various ligands of 2-iminomethylphenolate-type. The resulting pentacoordinate silicon complexes react with a variety of Brønsted acids HY to yield hexacoordinate salen silicon complexes (C6H5)(Y)Si-[o-O-C6H4-C(CH3)N-(CH2)n-NC(CH3)-o-C6H4-O] (Y = benzoate, picrate, 8-oxyquinolinate, 2-oxy-1,4-naphthoquinonate, p-tert-butylphenolate, (5-phenyltetrazol)-2-ide, fluoride, tetrafluoroborate). Hexacoordination of their Si-atoms was confirmed by 29Si NMR spectroscopy and, in some cases, by X-ray crystal structure analysis. Examples for similarities and differences in the coordination behavior of the silicon atom and its heavier congeners (Ge, Sn) in the salen-type coordination sphere as well as data regarding the nucleophilicity of some of these novel enamine complexes are presented. 相似文献
3.
Erica Farnetti Author Vitae 《Inorganica chimica acta》2010,363(3):467-473
The ability of organoiridium derivatives of catalyzing oligomerization and polymerization of terminal alkynes is markedly influenced by the nature of non-participative ligands coordinated to the metal. The dimeric species [Ir(cod)Cl]2 and [Ir(cod)(OMe)]2 (cod = 1,5-cyclooctadiene) as well as the phosphine complexes HIr(cod)(PR3)2 (PR3 = PPh3, P(p-MeOC6H4)3, P(o-MeOC6H4)Ph2, PCyPh2) catalyze the polymerization reaction, whereas the diphosphine derivatives HIr(cod)(P-P) (P-P = Ph2P(CH2)nPPh2 (n = 1-4), o-C6H4(PPh2)2) promote the regioselective formation of 1,2,4-trisubstituted benzenes. On the other hand, the iridium complexes with nitrogen chelating ligands Ir(cod)(N-N)X and Ir(hd)(N-N)X (hd = 1,5-hexadiene; N-N = 1,10-phenanthroline and substituted derivatives; X = halogen) catalyze alkynes polymerization. In most cases one catalytic reaction predominates over the other possible routes, so that polymerization often takes place in the absence of oligomerization side reactions, and conversely cyclotrimerization is rarely accompanied by formation of either polyene or dimers. 相似文献
4.
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
5.
Anupam Singh 《Inorganica chimica acta》2008,361(11):3159-3164
New and improved procedures are reported for the synthesis of [M(DBCOT)(μ-Cl)]2 (M = Rh, Ir; DBCOT = dibenzo[a,e]cyclooctatetraene) from MCl3(H2O)x or [M(COD)(μ-Cl)]2 and DBCOT. Treatment of [M(DBCOT)(μ-Cl)]2 with [(LAu)3(μ-O)]BF4(L = PPh3, PtBu3) yields the mixed-metal oxo complexes [M(DBCOT)(μ4-O)(AuL)2]2(BF4)2. Dimeric [Rh(DBCOT)(μ-OH)]2 is obtained from the reaction of [M(DBCOT)(μ-Cl)]2 with KOH in EtOH/H2O. All complexes except [Rh(DBCOT)(μ-Cl)]2 have been structurally characterized by single crystal X-ray diffraction. 相似文献
6.
Zhaofu Fei 《Inorganica chimica acta》2006,359(9):2635-2643
The reaction of the iminobiphosphines RNPPh2-PPh2, where R = C6H4(p-CN), C6H4(m-CN), C6H4(o-C6H5), C6F5 or C6H4(o-CF3), with one molecular equivalent of M(cod)Cl2 (M = Pd or Pt) results in a rearrangement of the NPP unit to the more commonly encountered P-N-P unit, forming mono-chelating complexes of general formula M{RN(PPh2)2}Cl2. The related reaction of the same range of iminobiphosphines with Pt(cod)Cl2 (but not Pd(cod)Cl2) in 2:1 ratio affords complexes of general formula [Pt{RN(PPh2)2}2]2Cl. All 15 complexes are isolated in moderate to high yield and they have been fully characterised by spectroscopic methods. Six complexes, viz. [M{C6H4(p-CN)N(PPh2)2}Cl2], [M{C6H4(m-CN)N(PPh2)2}Cl2] and [M{C6H4(o-C6H5)N(PPh2)2}Cl2] (M = Pd and Pt), have been characterised in the solid state by single crystal X-ray diffraction analysis. 相似文献
7.
Ten transition metal coordination complexes [Cu2(phen)(p-tpha)(μ-O)]n1, [Cu(m-tpha)(imH)2]n2, [Ni(5-Haipa)2(H2O)2]n3, [Ni(phen)2(H2O)2]·btc·[Ni(H2O)6]0.5·9H2O 4, [Co(2,5-pdc)(H2O)2]n·nH2O 5, [Co2(2,5-pdc)2(H2O)6]n·2nH2O 6, [Fe(2,5-Hpdc)2(H2O)2]·H2O 7, [Co(C6H4NO2)3]·H2O 8, [Fe2(μ2-btec)(μ2-H2btec)(bipy)2(H2O)2]n9, [Mn(phen)(2,5-pdc)(H2O)2]·H2O 10 (H4btec = 1,2,4,5-benzenetetracarboxylic acid, phen = 1,10-phenanthroline, 2,5-H2pdc = 2,5-pyridine-dicarboxylic acid, p-tpha = p-phthalic acid, m-tpha = m-phthalic acid, bipy = 2,2′-bipyridine, 5-H2aipa = 5-aminoisophthalic acid, imH = imidazole, H3btc = 1,3,5-benzenetricarboxylic acid) were synthesized through hydrothermal method. They were characterized by UV-Vis absorption spectra, single-crystal X-ray diffraction and surface photovoltage spectra (SPS). Structural analysis indicated that the complexes 1, 2, 3, 5, 6 and 9 were linked into infinite structures bridged by organic acid ligands. The other four complexes were molecular complexes and further connected to 2D or 3D structures by the hydrogen bonds. The SPS of complexes 1-10 indicate that there are positive response bands in the range of 300-800 nm showing different levels of photo-electric conversion properties. The intensity, position, shape and the number of the response bands in SPS are obviously different since the structure, species, valence, dn electrons configuration and coordinated environment of the center metals are different. There are good relationships between SPS and UV-Vis spectra. 相似文献
8.
Nuzhat Arshad Jamshed Hashim Muhammad Ali Minhas Javeria Aslam Tahira Ashraf Syeda Zehra Hamid Tahseen Iqbal Shumaila Javed 《Bioorganic & medicinal chemistry letters》2018,28(19):3251-3254
Four series of heterocyclic compounds, namely, tetrahydro-2H-1,3,5-thiadiazine thione derivatives were synthesized in good to excellent yields and were screened for their in vitro antileishmanial activities against Leishmania major (promastigotes). Most of the compounds showed significant antileishmanial activity within the range of IC50?=?15.48–39.36?μM when compared with standard pentamidine (IC50?=?14.95?μM). The structure-activity relationship showed that N-3 and N-5 substituents have a key role against leishmanicidal activity. The ester analogues (series B) were found to have a 1.5 to 5-fold reduced activity compared to their acidic counterparts. Cytotoxicity against mammalian mouse fibroblast 3?T3 cells was also evaluated and compared between the acid and its ester analogue. The reduction of antileishmanial activity and loss of toxicity in the newly developed THTT ester derivative indicates that these compounds can be used as a template study for the production of effective antileishmanial ester prodrugs. 相似文献
9.
The crystal structures of the complexes [RuCl(Nap-o-phd)(AsPh3)] and [RuBr(Nap-o-phd)(PPh3)] (where H2-Nap-o-phd = N,N′-bis(2-hydroxy-1-naphthaldehyde) o-phenylenediamine) have been determined by single crystal X-ray diffraction techniques. The antibacterial properties of the complexes have also been examined. 相似文献
10.
Benítez J Becco L Correia I Leal SM Guiset H Pessoa JC Lorenzo J Tanco S Escobar P Moreno V Garat B Gambino D 《Journal of inorganic biochemistry》2011,105(2):303-312
In the search for new therapeutic tools against diseases produced by kinetoplastid parasites five vanadyl complexes, [VIVO(L-2H)(phen)], including 1,10-phenanthroline (phen) and tridentate salicylaldehyde semicarbazone derivatives as ligands have been synthesized and characterized in the solid state and in solution by using different techniques. EPR suggested a distorted octahedral geometry with the tridentate semicarbazone occupying three equatorial positions and phen coordinated in an equatorial/axial mode. The compounds were evaluated in vitro on epimastigotes of Trypanosoma cruzi, causative agent of Chagas disease, Leishmania panamensis and Leishmania chagasi and on tumor cells. The complexes showed higher in vitro anti-trypanosomal activities than the reference drug Nifurtimox (IC50 values in the range 1.6-3.8 μM) and increased activities in respect to the free semicarbazone ligands. In vitro activity on promastigote and amastigote forms of Leishmania showed interesting results. The compounds [VO(L1-2H)(phen)] and [VO(L3-2H)(phen)], where L1 = 2-hydroxybenzaldehyde semicarbazone and L3 = 2-hydroxy-3-methoxybenzaldehyde semicarbazone, resulted active (IC50 2.74 and 2.75 μM, respectively, on promastigotes of L. panamensis; IC50 19.52 and 20.75 μM, respectively, on intracellular amastigotes of L. panamensis) and showed low toxicity on THP-1 mammalian cells (IC50 188.55 and 88.13 μM, respectively). In addition, the complexes showed cytotoxicity on human promyelocytic leukemia HL-60 cells with IC50 values of the same order of magnitude as cisplatin. The interaction of the complexes with DNA was demonstrated by different techniques, suggesting that this biomolecule could be a potential target either in the parasites or in tumor cells. 相似文献
11.
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
12.
Three ternary zinc complexes of the open chain polycarboxylic acid, tricarballylic (1,2,3-propane-tricarboxylic) acid (PTCH3) have been isolated and characterized with crystallographic and physicochemical techniques. [Zn(PTCH)(phen)(H2O)]2 · 4H2O (1) (where phen = 1,10-phenanthroline) has a unique dinuclear structure, while [Zn(PTCH)(bpy)]n · 3nH2O (2) and [Zn(PTCH)(epy)]n · 4nH2O (3) (where bpy = 4,4′-bipyridine and epy = 1,2-bis(4-pyridine)ethane) have 2D polymeric structures. The bis-deprotonated ligand, in all three complexes, uses for coordination only two oxygen atoms, which belong to the same carboxylate in 1, and to two different carboxylates in 2 and 3. 相似文献
13.
Reactions of orthometallated binuclear palladium complexes with NaER, obtained by NaBH4 reduction of R2E2 in methanol, gave complexes, [Pd2(μ-ER)2(C∩Y)2] (HC∩Y = N,N-dimethylbenzylamine (C6H5CH2NMe2), N,N-dimethylnaphthylamine (C10H7NMe2), tri-o-tolylphosphine {P(tol-o)3}; ER=SePh, SeMes, TePh, TeMes (Mes = 2,4,6-Me3C6H2). Similar reactions of [Pd2(μ-Cl)2(C10H6NMe2-C,N)2] with Pb(SMes)2 or MesSH in the presence of NaHCO3 gave chloro/thiolato-bridged complex [Pd2(μ-Cl)(μ-SMes)(C10H6NMe2-C,N)2]. The newly synthesized complexes were characterized by elemental analysis, UV-Vis, IR, NMR (1H, 13C, 31P, 77Se, 125Te) spectroscopy. These complexes crystallized out preferentially in sym-cis configuration. A low energy charge transfer transition has been identified from chalcogenolate centers to an emptyπ∗ orbital of cyclometallated ligand in absorption spectroscopy in these complexes. The structures of [Pd2(μ-Cl)(μ-SMes)(C10H6NMe2-C,N)2] (1) and [Pd2(μ-SePh)2(C10H6NMe2-C,N) 2] (3) have been established by single crystal X-ray diffraction analyses. In the former, the two palladium atoms are held together by chloro and thiolato bridges whereas in the latter, the two phenylselenolato ligands bridge two palladium atoms. The pyrolysis of [Pd(μ-TeMes)(C10H6NMe2-C,N)]2 (10) in a furnace gave Pd7Te3 whereas thermolysis in TOPO afforded primarily PdTe2. 相似文献
14.
Marcelle de L. Ferreira Thatyana R.A. Vasconcelos Maria C.S. Lourenço James L. Wardell Vitor F. Ferreira 《Carbohydrate research》2009,344(15):2042-2047
Six Schiff base derivatives of d-mannitol, 1,6-dideoxy-1,6-bis-{[(E)-arylmethylidene]amino}-d-mannitol (6: aryl = XC6H4: X = o-, m- and p- Cl or NO2), have been synthesized and evaluated for their in vitro antibacterial activity against Mycobacterium tuberculosis H37Rv using the Alamar Blue susceptibility test and the activity expressed as the minimum inhibitory concentration (MIC) in μg/mL. All three nitro derivatives exhibit significant activities: activities of (6d: X = o-NO2), (6e: X = m-NO2) and (6f: X = p-NO2) are 12.5, 25.0 and 25.0 μg/mL, respectively. When compared with first line drugs, such as ethambutol, they can be considered as a good starting point to develop new lead compounds for the treatment of multidrug-resistant tuberculosis. Characterization of the new compounds 6 is generally achieved spectroscopically. The structure of compound 3 has been confirmed by X-ray crystallography. 相似文献
15.
Sudipta Dalai Durga Sankar Chowdhuri Abhinandan Rana Ennio Zangrando 《Inorganica chimica acta》2010,363(14):3700-3705
Two coordination polymers of cadmium with formula [Cd(pyp)2(H2O)2]n (1) and {[Cd2(pyzca)3(atr)(H2O)]·H2O}n (2) [pypH = 3-pyridinepropionic acid, pyzcaH = 2-pyrazinecarboxylic acid and atrH = 5-aminotetrazole] have been synthesized and structurally characterized by X-ray single crystal diffraction analysis. Both complexes display 2D structures that extend into a 3D network by means of hydrogen bonding. The crystal packing of both complexes is reinforced by π-π interactions between adjacent aromatic rings. The fluorescence study indicates intraligand π-π* charge transfer, which is the reason for emission in both the complexes. 相似文献
16.
Sara Fornera 《Analytical biochemistry》2010,407(2):293-295
The assay conditions for the spectrophotometric quantification of horseradish peroxidase (HRP) with the chromogenic substrate o-phenylenediamine (OPD) at 25 °C in the presence of hydrogen peroxide (H2O2) were optimized. With [OPD]0 = 3.14 mM and [H2O2]0 = 80 μM at pH 7.2, the initial formation of only one of the possible reaction products and intermediates, 2,3-diaminophenazine (DAP, λmax = 417 nm), was observed. The rate of DAP formation during the first 30 min of reaction was followed spectrophotometrically and found to linearly depend on the HRP concentration between 5 and 45 pM under the conditions used. 相似文献
17.
Two novel bis(oxo)-bridged dinuclear manganese(IV) complexes with the binucleating ligand o-phenylenebis(oxamate) (opba), formulated as (Me4N)4[Mn2O2(opba)2] (1a) and (Me4N)2(Ph4P)2[Mn2O2(opba)2] · 8H2O (1b), have been synthesized and characterized structurally and magnetically. Like the parent complex (Ph4P)4[Mn2O2(opba)2] · 4H2O (1c), they possess unique Mn2(μ-O)2 bridging cores with two additional o-phenylenediamidate bridges which lead to exceptionally short Mn-Mn distances (2.63-2.67 Å) and fairly bent Mn-O-Mn angles (93.8-95.5°). Complexes 1a-c show a moderate to strong antiferromagnetic coupling between the two high-spin MnIV ions through the bis(oxo)bis(o-phenylenediamidate) quadruple bridge (−J = 70-164 cm−1; H = −JS1 · S2). Along this series, the −J values increase with the shortening of the Mn-Mn distance and/or the lessening of the Mn-O-Mn angle. Electronic structure calculations on model complexes reproduce the observed dependence of −J with the Mn-O-Mn angle at short intermetallic distances, and reveal that the magnetic coupling is dominated by the in-plane 3dx2-y2 type superexchange pathway via the oxo bridges with a small but nonnegligible contribution from direct 3dx2-y2 type Mn-Mn σ-bond. 相似文献
18.
Lei Jia Peng Jiang Zhong-yan Hao Long-hai Chen Ning Tang Qin Wang 《Inorganica chimica acta》2010,363(5):855-6176
Three novel ternary copper(II) complexes, [Cu2(phen)2(l-PDIAla)(H2O)2](ClO4)2·2.5H2O (1), [Cu4(phen)6(d,l-PDIAla)(H2O)2](ClO4)6·3H2O (2) and [Cu2(phen)2(d,l-PDIAla)(H2O)](ClO4)2·0.5H2O (3) (phen = 1,10-phenanthroline, H2PDIAla = N,N’-(p-xylylene)di-alanine acid) have been synthesized and structurally characterized by single-crystal X-ray crystallography and other structural analysis. Spectrometric titrations, ethidium bromide displacement experiments, CD (circular dichroism) spectral analysis and viscosity measurements indicate that the three compounds, especially the complex 3, strongly bind to calf-thymus DNA (CT-DNA). The intrinsic binding constants of the ternary copper(II) complexes with CT-DNA are 0.89 × 105, 1.14 × 105 and 1.72 × 105 M−1, 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 HeLa (Cervical cancer), HepG2 (hepatocarcinoma), HL-60 cells (myeloid leukemia), A-549 cells (pulmonary carcinoma) and L02 (liver cells). Investigations of antioxidation properties show that all the copper(II) complexes have strong scavenging effects for hydroxyl radicals and superoxide radicals. 相似文献
19.
Synthesis of a series of monoorganobismuth dithiocarboxylate complexes, [RBi(S2CAr)2] (R = Me, Ph, tol; Ar = Ph, tol), has been reported. They have been characterized by elemental analyses and spectroscopic methods. Molecular structures of [RBi(S2Ctol)2] (R = Me or Ph) have been established by single crystal X-ray diffraction studies. The bismuth atom in these complexes adopts a square pyramidal configuration with the R group at the apical position. In the solid state, these complexes show supra-molecular association devoid of Bi?S secondary interactions. Thermolysis of [RBi(S2Ctol)2] (R = Me or Ph) in refluxing diphenylether yielded Bi2S3 nanocrystals which were characterized by XRD, EDAX and SEM. The complex [PhBi(S2Ctol)2] has been employed for deposition of thin films of Bi2S3 by AACVD. 相似文献
20.
Claudio Pettinari Fabio Marchetti Paolo Natanti Sergey Semenov Vladislav Zolin 《Inorganica chimica acta》2006,359(12):4063-4070
Synthesis and spectroscopic characterization of new lanthanide complexes [Ln(QAD)3(EtOH)(H2O)], (Ln = Tb, Eu; HQAD = 1-phenyl-3-methyl-4-adamantylcarbonyl-pyrazol-5-one), [H3O][Tb(QAD)4], [Ln(QAD)3(N-N)] (Ln = Tb, Eu; N-N = 1,10-phenanthroline (Phen), 2,2′-bipyridyl (Bipy), 4,4′-dimethyl-2,2′-bipyridyl (4,4′-Me2Bipy)) are reported. The crystal structures of the proligand HQAD and of complexes [H3O][Tb(QAD)4] and [Tb(QAD)3(4,4′-Me2Bipy)] have been determined. In both complexes the lanthanide ions are in a square antiprismatic environment, the H3O+ cation in the former acid complex being stabilized by H-bonding. Luminescence studies have been performed on selected derivatives. 相似文献