共查询到20条相似文献,搜索用时 31 毫秒
1.
I. Tsivikas M. Alexiou A. A. Pantazaki C. Dendrinou-Samara D. A. Kyriakidis D. P. Kessissoglou 《Bioinorganic Chemistry and Applications》2003,1(1):85-97
The synthesis, characterization and the biological study of a series of Ni(ll)2(carboxylato)2 [12-
MCNi(II)N(shi)2(pko)2-4][12-MCNi(ii)N(sh03(pko)-4] (CH3OH)3(H3O) fused 12-membered metallacrowns with 10 metal ions and commercial available herbicides or anti-inflammatory drugs as carboxylato ligands are
reported. All the compounds have a mixed ligand composition with salicylhydroxamic acid and di-2-pyridylketonoxime
as chelate agents. The compounds construct metallacrown cores {[12-MCNi(n)N(sj02(pko)2-4][12-MCNi(ll)N(shO3(pko)-4]}2+ following the pattern [-Ni-O-N-]4. The neutral decanuclear [Ni(II)(A)]2[12-MCNi(II)N(shi)2(pko)2-4][12-MCNi(II)N(pko)3(pko)-4] fused metallacrown, consists of two [12-MCM(ox)N(ligand)-4] units the {Ni(ll)(A)[12-MCNi(II)N(shi)2(pko)2-4]} and {Ni(II)(A)[12-MCNi(II)N(shi)3(pko)-4]} with 1+ and 1- charge, respectively. Each metallacrown unit has four ring Ni(II) ions and one additional encapsulated Ni(II) ion in planar arrangement. The anionic unit is bonded with cationic one creating binuclear moieties. The herbicide or antiiflammatory carboxylato ligands are bridging the central octahedral nickel atom with a ring metal ion
in a bindetate fashion. The effect on DNA and their antibacterial activity was examined. The changes in the
mobility can be attributed to the altered structures of the pDNA treated with Ni(II) complexes. Evaluating the
data of the antibacterial activity of the compounds tested, we can conclude that nickel complexes present
strong antibacterial activity. 相似文献
2.
《Inorganica chimica acta》1987,131(1):33-37
From the Cu(II)NCO−3(5)-methylpyrazole (mpz) system two compounds Cu(NCO)2(mpz)2 and four compounds Cu(mpz·NCO)2 were isolated. The latter compounds contain carbamoylmethylpyrazolate anions as chelate ligands and are coligand isomers of the cyanate compounds. According to the results of indirect structural methods, the Cu(NCO)2(mpz)2 complexes have pseudooctahedral structures and differ in their polyhedron distortions. The Cu(mpz·NCO)2 complexes show tetragonally distorted six or five coordinate structures, possibly differing also by the methyl group position on the pyrazole ring. 相似文献
3.
The reaction of xanthosine-5′'-monophosphate disodium salt (5′-XMPNa2) with Pt(II), Cu(II) and Mg(II) ions produced compounds of the type cis- and trans-Pt(NH3)2(XMPNa2)nCl2·xH2O, where n = 1 or 2; Pt(XMPNa2)nCl2·xH2O, where n = 1-4, x = 1,4 & 6; Cu(XMP)·6H2O and Mg(XMP)·xH2O, where x = 9 or 4. In the complexes synthesized here at neutral pH values, the nucleotide binds through the N7-atom of the purine ring system, whereas for Cu(II) and Mg(II) compounds obtained at pH = 4 a direct metal-phosphate interaction as well as Nτ bonding is proposed. 相似文献
4.
Belma Zengin Kurt Çiğdem Bilen Adem Ergun Nahit Gençer Oktay Arslan 《Journal of enzyme inhibition and medicinal chemistry》2016,31(6):991-998
New secondary benzenesulphonamide-substituted coumarylthiazole derivatives were synthesized and their inhibitory effects on purified carbonic anhydrase I and II were evaluated using CO2 as a substrate. The result showed that all the synthesized compounds exhibited inhibitory activity on both hCA I and hCA II with N-(4-(2-oxo-2H-chromen-3-yl)thiazol-2-yl)naphthalene-2-sulphonamide (5f, IC50 value of 5.63 and 8.48?µM, against hCA I and hCA II, respectively) as the strongest inhibitor revealed from this study. Structure–activity relationship revealed that the inhibitory activity of the synthesized compounds is related to the type of the halogen and bulky substituent on the phenyl ring. In addition, the cupric reducing antioxidant capacities (CUPRAC) and ABTS cation radical scavenging abilities of the synthesized compounds were assayed. 4-methoxy-N-(4-(2-oxo-2H-chromen-3-yl)thiazol-2-yl)benzenesulphonamide (5e) exhibited the strongest ABTS and CUPRAC activity with IC50 value of 48.83?µM and A0.50 value of 23.29?µM, respectively. 相似文献
5.
《Bioorganic & medicinal chemistry》2016,24(18):4100-4107
Condensation of substituted anthranilic acids with 4-isothiocyanatoethyl-benzenesulfonamide led to series of heterocyclic benzenesulfonamides incorporating 2-mercapto-quinazolin-4-one tails. These sulfonamides were investigated as inhibitors of the human carbonic anhydrase (hCA, EC 4.2.1.1) isoforms hCA I and II (cytosolic isozymes), as well as hCA XII (a transmembrane, tumor-associated enzyme also involved in glaucoma-genesis). The new sulfonamides acted as medium potency inhibitors of hCA I (KIs of 28.5–2954 nM), being highly effective as hCA II (KIs in the range of 0.62–12.4 nM) and XII (KIs of 0.54–7.11 nM) inhibitors. All substitution patterns present in these compounds (e.g., halogens, methyl and methoxy moieties, in positions 6, 7 and/or 8 of the 2-mercapto-quinazolin-4-one ring) led to highly effective hCA II/XII inhibitors. These compounds should thus be of interest as preclinical candidates in pathologies in which the activity of these enzymes should be inhibited, such as glaucoma (CA II and XII as targets) or some tumors in which the activity of isoforms CA II and XII is dysregulated. 相似文献
6.
Zahid H. Chohan Claudiu T. Supuran 《Journal of enzyme inhibition and medicinal chemistry》2013,28(5):463-468
Keflin (kefl) interacts with Co(II), Cu(II), Ni(II) and Zn(II) metal ions leading to complexes of the type M(kefl)2Cl2 and M(kefl)Cl2, which have been characterized by physicochemical and spectroscopic methods. Magnetic moment, IR, electronic spectral and elemental analyses data suggest that keflin behaves tridentately forming octahedral or trigonal bipyramidal complexes with the metal ions mentioned above. The new compounds have been screened in-vitro for antibacterial and cytotoxic activity against Escherichia coli, Klebsiella pneumoniae, Proteus mirabilis, Pseudomonas aeruginosa, Salmonella typhi, Shigella dysentriae, Bacillus cereus, Corynebacterium diphtheriae, Staphylococcus aureus and Streptococcus pyogenes bacterial strains. Compounds, 4 and 8 showed promising activity (90%) against seven, compound 6 showed significant activity (52%) against four and, compounds 1 and 5 showed activity (40%) against three test bacterial strains at concentration of 10 μM. 相似文献
7.
Muhammet Tanc Fabrizio Carta Murat Bozdag Andrea Scozzafava Claudiu T. Supuran 《Bioorganic & medicinal chemistry》2013,21(15):4502-4510
A series of 7-substituted sulfocoumarins and 3,4-dihydrosulfocoumarins was obtained by cyclization of the methanesulfonate of 2,4-dihydroxy- or 2-hydroxy-4-methoxybenzaldehyde, followed by derivatization reactions. The new compounds incorporate a range of substituents in position 7 of the heterocyclic ring (hydroxyl, methoxy, carboxylic and alkylsulfonate ester). The compounds were tested for the inhibition of the zinc enzyme human (h) carbonic anhydrase (hCA, EC 4.2.1.1). Unlike the 6-substituted sulfocoumarins which were potent hCA IX and XII inhibitors and ineffective hCA I and II inhibitors, compounds from this series showed low nanomolar hCA II inhibitory properties, and inhibited the mitochondrial isoform hCA VA with KIs in the range of 91–9960 nM, but were ineffective as hCA I, IX and XII inhibitors. The structure activity relationship for this class of inhibitors was rather clear, with the nature of the 7-substituent strongly influencing hCA VA inhibition, whereas the nature of these groups were less relevant for hCA II inhibition (all reported compounds were highly effective hCA II inhibitors, with KIs in the range of 1.5–8.4 nM). Since both hCA II and hCA VA are important drug targets (hCA II for antiglaucoma agents; hCA VA for antiobesity drugs), these isoform-selective inhibitors reported here may be considered of interest for various biomedical applications. 相似文献
8.
《Inorganica chimica acta》1986,125(3):159-166
This paper describes the synthesis of compounds of Ni(II) with uracil, uridine and the nucleotides 5′UMP, 5′CMP, 5′GMP and 5′IMP, and their characterization, carried out by elemental analysis, by studying the infrared spectra, diffuse reflectance and conductivity measurement.In the complexes of NiURA (and NiURD) with acetate, direct coordination of the metal ion to the C4O group of the pyrimidine ring is inferred from the changes observed on the infrared spectrum of the corresponding bands at vCO. The variations in frequency of the vCOO symmetric and asymmetric bands of the acetate group together with the conductivity and reflectance results seem to indicate the dimer structure of the compounds.In the compounds of NiURA (and NiURD) with ethylenediamine indirect bonding of Ni(II)to the pyrimidine ring is inferred, probably established through hydrogen bonds involving the C4O groups in the base or nucleoside and the −NH2 groups in the ethylenediamine.In the complexes of Ni-nucleotide, bonding seems to occur through the heterocyclic ring (C4O for 5′UMP, N(3) for 5′CMP, N(7) for 5′GMP and 5′IMP) together with additional interactions through the phosphate group. 相似文献
9.
Insight into shock-induced chemical reaction from the perspective of ring strain and rotation of chemical bonds 总被引:1,自引:0,他引:1
Bisheng Tan Xinping Long Jinshan Li Fude Nie Jinglun Huang 《Journal of molecular modeling》2012,18(12):5127-5132
Density functional theory BLYP/DNP and hyperhomodesmotic equations were employed to calculate ring strain energy, the bond dissociation energy of X–NO2 (X=C, N) and the charges on the nitro groups of several four-membered and six-membered heterocycle compounds. BLYP/DNP and LST/QST + CG method were also applied to calculate bond rotational energy of X–NO2 (X=C, N) of above mentioned compounds. It indicated that ring strain energy of four-membered heterocycle nitro compounds is apparently higher than that of six-membered heterocycle nitro compounds. Predictably, ring-opening reactions may preferentially occur for those compounds containing higher ring strain energy under shock. In addition, C–NO2 bonds in these compounds may rotate easier than N–NO2 bonds in response to the external shock. As for N–NO2 bonds in these compounds, they also respond to the external shock by the rotation of N–NO2 bonds, once to the saddle point of the rotational energy barrier, the whole molecule will become relaxed, N–NO2 bond becomes weaker and eventually leads to the breakage. When one ?C=O, ?C=NH or ?NH2 group is introduced to the six-membered heterocycle, the charges on the nitro groups of the new compound decrease drastically, and ring strains increase remarkably. It can be predicted that the new compounds will be more sensitive to shock, and the viewpoint is confirmed by the experimental results of shock sensitivity (small scale gap test) of several explosives. 相似文献
10.
For the development of novel anticancer agents, we designed and synthesized a total of 37 perimidine o-quinone derivatives containing the o-quinone group at the A or B ring and different substituents (alkyl groups, aryl groups or heterocycles) at the C ring of the compounds. The structure-activity relationships (SARs) were established based on the cytotoxicity data of compounds from the HL-60, Huh7, Hct116, and Hela cell lines. The cytotoxicity results showed that most compounds exhibited potent cytotoxicity. In particular, compound b-12 showed the best anti-proliferative activity (IC50 ≤ 1 μM) against four cancer cell lines and strong potency against the HL-60/MX2 (0.47 μM) cell line, which is resistant to Topo II poisons. Further studies showed that b-12 exhibited potent Topo IIα inhibitory activity (IC50 = 7.54 μM) compared with Topo I, which acted as a class of non-intercalative Topo IIα catalytic inhibitor by inhibiting the ATP binding site of Topo II. Cell apoptosis and cell cycle assays confirmed that b-12 could induce the apoptosis of Huh7 cells in a dose-dependent manner. 相似文献
11.
Two novel bolaamphiphile based dicarboxylic ligands L1H2 and L2H2 are synthesized by desymmetrizing aromatic anhydrides. The corresponding Cu(II) complexes [Cu(L1) · EtOH]2 (1), [Cu(L2) · (CH3CN)]2 (2) are synthesized and characterized. The crystal structure obtained for (1) and (2) indicates that they are new class of tetralactone type macrocyclic Cu(II) chelate complexes with paddle wheel Cu2-acetate cage structure. The 1:1, Cu(II) and ligand ratio leads into formation of a novel binuclear Cu(II) tetracarboxylate complexes. The macrocyclic chelate ring size in compounds 1 and 2 was altered from [15] membered to [19] membered by introducing phthalyl and diphenyl head groups as discussed in detail. The single crystal X-ray structure shows the Cu(II)?Cu(II) distance 2.613(13) Å for 1 and 2.626(13) Å for 2, the corresponding room temperature EPR spectra recorded for powdered polycrystalline samples indicate the existence of Cu(II)?Cu(II) dimeric system. 相似文献
12.
The lithium β-diketiminate (1c, [Li{N(2,6-iPr2C6H3)C(Ph)CHC(tBu)NH}]2 represented as (LiL)2) reacted with 3d-metal (II) chlorides to afford the corresponding compounds (2-7). All metal compounds were fully characterized by elemental, spectroscopic analyses and the single-crystal X-ray diffraction. The coordination geometries around the metals are shown to be tetrahedral within the trinuclear Co2Li compound (2), planar in ML2 (M = Co, 3), pseudo-tetrahedral conformation in the ML2 with M as Mn (4), Fe (5) or Zn (6), and square planar in the dinickel compound (7). Indicated by the trimetallic Co2Li compound 2, a six-membered ring is constructed of three metal atoms and three bridged chlorides as a twisted conformation. An inversion center is present in the centroid of the Ni2Cl2 four-membered ring within compound 7. The plausible mechanism of forming ML2 was proposed through the chloro-bridged multinuclear compounds on the basis of isolated intermediates of trinuclear (2) and dinuclearic (7) compounds. Upon treatment with methylaluminoxane (MAO), the nickel compound 7 possessed good activity towards ethylene oligomerization, whereas the other metal compounds showed moderate activities towards ethylene polymerization. 相似文献
13.
The synthesis and characterization of four new complexes with the bioactive ligand 3-aminoflavone (3-af) are reported. The complexes of general formula [M(3-af)2(H2O)2](NO3)2 · nH2O], where M = Co(II), Ni(II), and Zn(II), and n = 0, 2, 0, respectively, and [Cu(3-af)2(NO3)2] compound were prepared and studied. In particular, to investigate the binding in detail, the crystal structures of the free ligand (3-af) and [Cu(3-af)2(NO3)2] (1) were determined. The new coordination compounds were identified and characterized by elemental analysis, magnetic measurements, and infrared and ligand-field spectra. The crystal structure of the Cu(II) complex reveals that the ligand acts as a N,O-bidentate chelate ligand forming a five-membered ring with the copper(II) ion. The copper(II) ion is octahedrally surrounded by the two amino nitrogens and two carbonyl oxygens from two chelating organic ligands in trans arrangement. Two molecules of coordinated nitrate anions occupy axial positions. The spectral and magnetic properties are in accordance with the structural data of the copper(II) compound. From X-ray powder-diffraction patterns and IR spectra, the complexes of nickel(II) (2) and cobalt(II) (3) were found to be mutually isomorphous. The results of the spectroscopic studies suggest a mononuclear structure of 2 and 3 complexes. The variable-temperature (1.8-300 K) magnetic susceptibility data of 2 indicate a weak ferromagnetic interaction. The magnetic behavior of complex 3 is characteristic of cobalt(II) systems with an important orbital contribution via spin-orbit-coupling and also suggests a weak ferromagnetic interaction. 相似文献
14.
A series of macrobicyclic mono and binuclear nickel(II) complexes of type [NiL](ClO4) and [Ni2L](ClO4)2, where L is macroyclic ligand derived from the precursor compound 3,4:10,11-dibenzo-1,13[N,N′-bis{(3-formyl-2-hydroxy-5-methyl)benzyl}diaza]-5,9-dioxocyclopentadecane, have been synthesized in order to examine electrochemical and catalytic studies on the basis of macrocyclic ring size. The macrocycle consists of three dissimilar compartments arising from ether oxygen, tertiary nitrogen and imine nitrogen atoms. Electrochemical studies have shown that the mononuclear nickel(II) complexes undergo quasireversible single step one electron reduction and oxidation and binuclear nickel(II) complexes undergo two quasireversible one electron reduction and oxidation. The EPR silent nature is ascribed to Ni(II) state and all the nickel(II) complexes have square planar geometry and are diamagnetic in nature. The complexes were subjected to hydrolysis of 4-nitrophenyl phosphate and the catalytic activities of the complexes are found to increase with macrocyclic ring size of the complexes. As the macrocyclic ring size of the complexes increases, the spectral, electrochemical and catalytic studies of the complexes show remarkable variation due to distortion in the geometry around the nickel(II) centre. 相似文献
15.
Suwanna Vangveravong Michelle Taylor Jinbin Xu Jinquan Cui Wesley Calvin Sonja Babic Robert R. Luedtke Robert H. Mach 《Bioorganic & medicinal chemistry》2010,18(14):5291-5300
A series of indole, 7-azaindole, benzofuran, and benzothiophene compounds have been prepared and evaluated for affinity at D2-like dopamine receptors. These compounds share structural elements with the classical D2-like dopamine receptor antagonists haloperidol, N-methylspiperone and benperidol. Two new compounds, 4-(4-iodophenyl)-1-((4-methoxy-1H-indol-3-yl)methyl)piperidin-4-ol (6) and 4-(4-iodophenyl)-1-((5-methoxy-1H-indol-3-yl)methyl)piperidin-4-ol (7), were found to have high affinity to and selectivity for D2 versus D3 receptors. Changing the aromatic ring system from an indole to other heteroaromatic ring systems reduced the D2 binding affinity and the D2 versus D3 selectivity. 相似文献
16.
A series of twenty four hydroxy-trifluoromethylpyrazoline-carbonyl-1,2,3-triazoles and four hydrazones bearing benzenesulfonamide moieties was obtained by condensation of carboxyhydrazides with substituted 1,3-diketones. All the newly synthesized compounds were investigated as inhibitors of physiologically and pharmacologically relevant human (h) carbonic anhydrsae (CA, EC 4.2.1.1) cytosolic isoforms hCA I and II, as well as transmembrane tumor-assosciated isoforms hCA IX and XII. These compounds exhibited excellent CA inhibitory potency against the four CA isoenzymes as compared to clinically used reference drug acetazolamide (AAZ). Some compounds bearing bulkier group at C-5′ position of 1,2,3-triazoles ring were weaker inhibitors of hCA I. Inhibition assay against hCA II indicates, that several derivatives exhibited upto 27-fold more effective inhibitory activity compared to AAZ. Five of the assayed compounds displayed low nanomolar potency (Ki ≤ 10 nM) against hCA IX, whereas five compounds were found to be endowed with excellent inhibitory potencies (Ki ≤ 5 nM) against hCA XII. The biological activity profile presented herein will be useful for designing new leads and provide candidates for preclinical investigations. 相似文献
17.
Rawny Galdino Gouveia Amélia Galdino Ribeiro Miguel Ângelo Santos Pinheiro Segundo Jamerson Ferreira de Oliveira Maria do Carmo Alves de Lima Túlio Ricardo Couto de Lima Souza Sinara Mônica Vitalino de Almeida Ricardo Olímpio de Moura 《Bioorganic & medicinal chemistry》2018,26(22):5911-5921
Nine new spiroacridine derivatives were synthetized by introducing cyano-N-acylhydrazone group between the acridine and phenyl-substituted rings followed by spontaneous cyclization. The new compounds were assayed for their DNA binding properties, human topoisomerase IIα inhibition and bovine serum albumin (BSA) interaction. Besides, docking analysis were performed in order to better understanding the biomolecule-compounds interactions. All compounds interacted with BSA which was demonstrated by the fluorescence suppression constant of 104?M?1. Compounds with chloro and NO2 substituents at that para-position on phenyl ring demonstrated the best results for BSA interaction. DNA binding constant determined by UV–vis data demonstrated high values for AMTAC-11 and AMTAC-14, 1.1?×?108?M?1 and 4.8?×?106?M?1, respectively, and all others presented constant values of 105?M?1. AMTAC-06 with chloro at para-position on phenyl ring presented a topoisomerase II inhibition of 84.34% in comparison to the positive controls used. Docking studies indicated that AMTAC-06 is able to intercalate the DNA base pairs at topoisomerase IIα active site, preventing DNA connection after break, in a process known as poisoning. Topoisomerase enzyme inhibition result was correlated to BSA interaction profile, since AMTAC-06 showed the best results in both analysis. The findings obtained here proved that methoxy or chloro substitution on phenyl ring at para-position is fundamental for in vitro activity of new spiroacridine derivatives, and indicates that AMTAC-06 is a promising entity and should serve as a lead compound in the development of new DNA and protein binders, as well as human topoisomerase II inhibitors. 相似文献
18.
H. Kozlowski J. P. Aubert M. Gusse P. Chevaillier M. H. Loucheux-Lefebvre 《Biopolymers》1984,23(7):1241-1248
The interaction of Cu(II) with the protamine scylliorhinine Z3 was studied by means of CD measurements. At a 1:1 molar ratio, three complexes are formed. (1) In the pH range 5–6.5, the results suggest the formation of a five-membered chelate ring through the coordination of two nitrogen atoms, the N-terminal and the contiguous peptide nitrogen. (2) At pH ≥ 6.4, there is involvement of the lateral NH2 group of Arg; at pH 6.5–8, the formation of a 3N cupric complex is strongly suggested. (3) At pH ≥ 8, results indicate the formation of a 4N complex as a major species in Cu(II)-Z3 solution. The transformation from a 2N to a 3N complex, and from a 3N to a 4N complex was followed with the help of the σ(αNH2) → Cu(II) charge-transfer dichroic band transitions. At Cu(II):Z3 molar ratios ≥ 2 and at pH > 8, a new dichroic band appears, indicating the involvement of the tyrosine residue side chain in metal-ion complexation. 相似文献
19.
Fe(II)/α-ketoglutarate (αKG)-dependent hydroxylases catalyze an amazing diversity of reactions that result in protein side-chain modifications, repair of alkylated DNA/RNA, biosynthesis of antibiotics and plant products, metabolism related to lipids, and biodegradation of a variety of compounds. These enzymes possess a β-strand “jellyroll” structural fold that contains three metal-binding ligands found in a His1-X-Asp/Glu-Xn-His2 motif. The cosubstrate, αKG, chelates Fe(II) using its C-2 keto group (binding opposite the Asp/Glu residue) and C-1 carboxylate (coordinating opposite either His1 or His2). Oxidative decomposition of αKG forms CO2 plus succinate and leads to the generation of an Fe(IV)-oxo or other activated oxygen species that hydroxylate the primary substrate. The reactive oxygen species displays alternate reactivity in related enzymes that catalyze desaturations, ring expansions, or ring closures. Other enzymes resemble the Fe(II)/αKG-dependent hydroxylases in terms of protein structure or chemical mechanism but do not utilize αKG as a substrate. This review describes the reactions catalyzed by this superfamily of enzymes, highlights key active site features revealed by structural studies, and summarizes results from spectroscopic and other approaches that provide insights into the chemical mechanisms. 相似文献
20.
Three new compounds are reported with the tetradentate ligand (N,N′-bis(2-Pyridylmethyl)-1,3-propanediamine) (abbreviated as pypn), two mononuclear compounds i.e. [Co(pypn)(C2O4)](ClO4) (1), [Mn(pypn)(C2O4)](ClO4) (2) and one dinuclear compound [Ni2(pypn)2(C2O4)](ClO4)2(C2H6O)1/4(H2O) (3). In the Co(III) and Mn(II) complexes the oxalate behaves as bidentate ligand, chelating the metal in the O,O′ mode, whereas in the Ni(II) compound the oxalate behaves as tetradentate ligand binding each Ni(II) ion by two oxygen atoms and bridging the two metallic centers.The synthesis, X-ray crystal structure of all three compounds and their spectroscopic properties are presented in detail. The geometry around the Co3+, Mn3+, Ni2+ ions is essentially octahedrally based, while the stabilization of the crystal lattice in all cases is maintained by interesting hydrogen bond systems. 相似文献