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1.
The copper aminotropones Cu[ON(R′)C7H4R-4]2 [R = H, R′ = Me (13), Et (14), n-Pr (15), n-Bu (16), Bz (17), MenOCH2CH2 (20); R = i-Pr, R′ = Me (18), n-Pr (19), MenOCH2CH2 (21)] have been prepared from the corresponding aminotropones HN(R′)OC7H4R-4 (17) by reacting with copper(II) acetate in aqueous ethanol. 20, 21 contain the flavourant, menthol, as part of the ligand. The structures of 5 (R = H, R′ = Bz), a hydrogen-bonded dimer, 14 and 20, both incorporating square-planar, four-coordinate copper centres, have been determined by X-ray crystallography. The antibacterial activities of complexes 13, 17, 20 and 21 have been assayed against Staphylococcus waneri, an in vitro model of plaque inhibition effects, and found to be more active than a commercial toothpaste formulation, but less active than the O,O-chelated copper(II) complex of ethylmaltol.  相似文献   

2.
The mononuclear pyrazolyl complexes [PdCl2(HIPz)2] (1), [PdBr2(HIPz)2] (2), [PdI2(HIPz)2] (3), [Pd(SCN)2(HIPz)2] (4), and [Pd(NHCOIPz)2] (5) have been prepared. Compound 1 was obtained from the displacement of acetonitrile from [PdCl2(CH3CN)2] precursor by the 4-iodopyrazole (HIPz) ligand, whereas 25 were synthesized by substitution of the chlorido in 1 by the respective anionic group. The compounds were characterized by elemental analysis, infrared spectroscopy, and 1H NMR spectroscopy. The thermal behavior of 15 has been studied by TG and DTA. The thermal stability of [PdX2(HIPz)2] compounds varies according to the trends X = Cl? < I? ? SCN?< Br?. No stable intermediates were isolated during the thermal decompositions due to the overlap of the degradation processes. The final products of the thermal decompositions were characterized as metallic palladium by X-ray powder diffraction.  相似文献   

3.
Four new mononuclear triazido-cobalt(III) complexes [Co(L 1/2/4 )(N3)3] and [Co(L 3 )(N3)3]·CH3CN where L 1  = [(2-pyridyl)-2-ethyl]-(2-pyridylmethyl)-N-methylamine, L 2  = [(2-pyridyl)-2-ethyl]-[6-methyl-(2-pyridylmethyl)]-N-methylamine, L 3  = [(2-pyridyl)-2-ethyl]-[3,5-dimethyl-4-methoxy-(2-pyridylmethyl)]-N-methylamine, and L 4  = [(2-pyridyl)-2-ethyl]-[3,4-dimethoxy-(2-pyridylmethyl)]-N-methylamine, respectively, were synthesized and structurally characterized. The four complexes were characterized by elemental microanalyses, IR and UV–VIS spectroscopy and X-ray single crystal crystallography. The complexes display two strong IR bands over the frequency region 2,020–2,050 cm?1 assigned for the asymmetric stretching frequency, νa(N3) of the coordinated azides indicating facial geometry. The molecular structure determinations of the complexes were in complete agreement with fac-[Co(L)(N3)3] conformation in distorted octahedral Co(III) environment.  相似文献   

4.
In this paper, N-(2-[18F]fluoropropionyl)-β-glutamic acid 8 ([18F]FP-β-Glu), a new N-substituted 18F-labeled amino acid tracer, was synthesized from the precursor 4 (diethyl 3-(2-bromopropanamido)pentanedioate) via a two-step reaction on the modified FDG synthesizer. The radiochemical yield was 20 ± 5% (n = 10, decay-corrected) from [18F]fluoride within 40 min, the radiochemical purity was 98%. Moreover, microPET studies showed that [18F]FP-β-Glu 8 exhibited rapid tumor uptake and good tumor-to-lung ratio in SPC-A-1 tumor-bearing mice. A high accumulation of radioactivity was found in the kidneys and bladder, which suggested that the tracer was mainly eliminated through the urinary system.  相似文献   

5.
From extraction experiments and $ \gamma $ -activity measurements, the exchange extraction constant corresponding to the equilibrium Tl+ (aq) + 1·Cs+ (org) ? 1·Tl+ (org) + Cs+ (aq) taking place in the two-phase water–phenyltrifluoromethyl sulfone (abbrev. FS 13) system (1 = calix[4]arene-bis(t-octylbenzo-18-crown-6); aq = aqueous phase, org = FS 13 phase) was evaluated as log K ex (Tl+, 1·Cs+) = 1.7 ± 0.1. Further, the extraordinarily high stability constant of the 1·Tl+ complex in FS 13 saturated with water was calculated for a temperature of 25 °C: log β org(1·Tl+) = 13.1 ± 0.2. Finally, by using quantum mechanical DFT calculations, the most probable structure of the cationic complex species 1·Tl+ was derived. In the resulting 1·Tl+ complex, the “central” cation Tl+ is bound by eight bond interactions to six oxygen atoms from the respective 18-crown-6 moiety and to two carbons of the corresponding two benzene rings of the parent receptor 1 via cation–π interaction.  相似文献   

6.
A series of six organotin(IV) carboxylates [Me2SnL2] (1), [n-Bu2SnL2] (2), [n-Oct2SnL2] (3), [Me3SnL] (4), n-Bu3SnL (5) and [Ph3SnL] (6), where L = 3-(4-cyanophenyl) acrylic acid have been synthesized and characterized by elemental analysis, FT-IR and NMR (1H, 13C). The complex (4) was also analyzed by single crystal X-ray analysis which showed distorted trigonal bipyramidal geometry with polymeric bridging behavior. The complexes 16 were screened for antimicrobial activities and cytotoxicity. The results showed significant activity with few exceptions. The catalytic activity of complexes was assessed in transesterification reaction of Brassica campestris oil (triglycerides) to produce biodiesel (fatty acid methyl esters). The results showed that triorganotin(IV) complexes exhibited good catalytic activity than their di-analogues.  相似文献   

7.
From extraction experiments and γ-activity measurements, the extraction constant corresponding to the equilibrium Cs+(aq) + I?(aq) + 1(nb) ? Cs+(nb) + I?(nb) taking place in the two–phase water–nitrobenzene system (1 = 1,3-alternate-25,27-bis(1-octyloxy)calix[4]arene-crown-6; aq = aqueous phase, nb = nitrobenzene phase) was evaluated as log K ex (Cs+, I?) = 2.9 ± 0.1. Further, the stability constant of the Cs+ complex in nitrobenzene saturated with water was calculated for a temperature of 25 °C: log βnb (Cs+) = 8.8 ± 0.1. Finally, by using quantum–mechanical DFT calculations, the most probable structure of the resulting cationic complex species Cs+ was derived.  相似文献   

8.
From extraction experiments and γ-activity measurements, the exchange extraction constant corresponding to the equilibrium Ag+ (aq) + Cs+(org) ? Ag+ (org) + Cs+ (aq) taking place in the two-phase water–phenyltrifluoromethyl sulfone (FS 13) system (1 = calix[4]arene-bis(t-octylbenzo-18-crown-6); aq = aqueous phase, org = FS 13 phase) was evaluated as logK ex (Ag+, Cs+) = ?1.5 ± 0.1. Further, the stability constant of the Ag+ complex in FS 13 saturated with water was calculated for a temperature of 25 °C: log β org(Ag+) = 10.1 ± 0.2. Finally, by using quantum mechanical DFT calculations, the most probable structure of the cationic complex species Ag+ was derived. In the resulting Ag+ complex, the “central” cation Ag+ is bound by eight bond interactions to six oxygen atoms from the respective 18-crown-6 moiety and to two carbons of the corresponding two benzene rings of the parent ligand 1 via cation-π interaction.  相似文献   

9.
Complexation of alkali metal cations with 5,11,17,23-tetra-tert-butyl-26,28,25,27-tetrakis(O-methyl-D-α-phenylglycylcarbonylmethoxy)calix[4]arene (L) was studied by means of spectrophotometric, conductometric and potentiometric titrations at 25 °C. The solvent effect on the binding ability of L was examined by using two solvents with different affinities for hydrogen bonding, viz. methanol and acetonitrile. Despite the presence of intramolecular NH···O=C hydrogen bonds in L, which need to be disrupted to allow metal ion binding, this calix[4]arene amino acid derivative was shown to be an efficient binder for smaller Li+ and Na+ cations in acetonitrile (lg K LiL  > 5, lg K NaL  = 7.66), moderately efficient for K+ (lg K KL  = 4.62), whereas larger Rb+ and Cs+ did not fit in its hydrophilic cavity. The complex stabilities in methanol were significantly lower (lg K NaL  =  4.45, lg K KL  = 2.48). That could be explained by different solvation of the cations and by competition between the cations and methanol molecules (via hydrogen bonds) for amide carbonyl oxygens. The influence of cation solvation on complex stability was most pronounced in the case of Li+ for which, contrary to the quite stable LiL + complex in acetonitrile, no complexation was observed in methanol under the conditions used.  相似文献   

10.
A glycol ether modified precursor, [Nb{O(CH2CH2O)2}(OPri)3] (A) was prepared by the reaction of Nb(OPri)5 with O(CH2CH2OH)2 in 1:1 molar ratio in anhydrous benzene. Further reactions of A with a variety of internally functionalized oximes in different molar ratios, yielded heteroleptic complexes of the type, [Nb{O(CH2CH2O)2}(OPri)3?n{ON = C(CH3)(Ar)}n] (1–9) {where Ar = C4H3O-2, n = 1 [1], n = 2 [2], n = 3 [3]; C4H3S-2, n = 1 [4], n = 2 [5], n = 3 [6]; C5H4N-2, n = 1 [7], n = 2 [8], n = 3 [9]}. All the above derivatives have been characterized by elemental analyses, FT-IR, NMR (1H, 13C {1H}) and FAB mass studies. Spectral studies of 1–9 suggest the presence of mono- and bi-dentate mode of oxime moieties, in the solution and in the solid states, respectively. FAB mass studies indicate monomeric nature for 3 and dimeric nature for A. TG curves of A and 6 show their low thermal stability. Soft transformation of A and 3 to pure niobia, a and b, respectively have been carried out by sol–gel technique. The XRD patterns of niobia a and b suggest the formation of nano-size crystallites of average size of 10.8 and 19.5 nm, respectively. The XRD patterns also indicate the formation of monoclinic phase of the niobia in both the cases. Absorption spectra of a and b suggest energy band gaps of 4.95 and 4.39 eV, respectively.  相似文献   

11.
Two unsymmetrical complexes, [NiL1]ClO4 (1) and [NiL2]ClO4 (2) have been synthesized and characterized by IR, UV, ES-MS and single crystal X-ray diffraction, where HL1 and HL2 are, respectively, the [1+1] condensation products of 2,6-diformyl-4-X-phenol (X = F or CH3) with N 1-(2-aminoethyl)-N 2-(4-nitrobenzyl) ethane-1,2-diamine. The coordination geometry of the metal in both complexes can be approximately described as square planar with a mean plane deviation of 0.032 Å in complex 1 and 0.027 Å in complex 2, respectively. The binding activities of the complexes toward calf-thymus DNA have been analyzed by spectroscopy and viscosity methods. The binding constants of 1 and 2 obtained from UV spectroscopic studies are 5.43 × 105 and 1.83 × 105 M?1, respectively, while the linear Stern–Volmer quenching constants obtained from fluorescence spectroscopic studies are 0.83 × 103 and 0.71 × 103 M?1, respectively. The cyclic voltammograms of the complexes show a pseudo-reversible electrochemical process.  相似文献   

12.
Three new Schiff base complexes, namely [Mn(L)Cl] · H2O (1), [Co(L)Cl]2 · 2CH3COCH3 (2) and [Co(L)NCS]2 (3), where H2L = 2,2′-[propane-1,2-diylbis(nitriloeth-1-yl-1-ylidene)]diphenol, have been prepared and characterized. The syntheses of 1 and 2 have been achieved by reacting equimolar amounts of the respective metal chloride and the tetradentate Schiff base ligand (H2L). While the mononuclear Mn(III) complex 1 was obtained with MnCl2 in acetone medium, the same synthetic system yielded the binuclear Co(III) complex 2 in the presence of CoCl2. Dissolution of 1 and 2 followed by crystallization with ammonium thiocyanate in methanol yielded two isostructural phenoxo-bridged binuclear complexes, namely [Mn(L)NCS]2 (previously reported by us) and a new complex [Co(L)NCS]2 (3), respectively. All the complexes 13 have been characterized by microanalytical, spectroscopic, single crystal X-ray diffraction and other physicochemical studies. Structural studies reveal that 1 adopts a distorted tetragonal pyramidal geometry while 2 and 3 comprise dimeric Co(III) units with bridging phenolate oxygen atoms. All the complex units in 1–3 and the respective solvent molecules are held together by weak intermolecular H-bonding to constitute a supramolecular network in the solid state. The antibacterial activity of the complexes has been tested against some Gram(+) and Gram(?) bacteria.  相似文献   

13.
A new ligand, (2-ethoxy-6-(1H imadazo[4,5-f][1,10]phenanthroline-2-yl)phenol) (HEPIP) and its three Co(III) complexes [Co(phen)2(HEPIP)](ClO4)3 (1), [Co(bpy)2(HEPIP)](ClO4)3 (2) and [Co(dmb)2(HEPIP)](ClO4)3 (3) have been synthesized and characterized. All three Co(III) complexes exhibited antitumor activity against four human tumor cell lines. The interaction of these complexes with calf thymus DNA was studied by absorption and emission spectroscopy, viscosity measurements and DNA cleavage assays. The DNA-binding constants of complexes 1, 2 and 3 were determined as 6.13 × 105, 4.46 × 105 and 3.72 × 105 M?1, respectively. The complexes appear to interact with DNA through intercalation. Studies on the mechanism of photocleavage indicated that both superoxide anion radical and singlet oxygen may play an important role.  相似文献   

14.
A series of 1,2,3-triazole-linked calix[4]arene ionophores comprised of different O-donor groups (OH, COOEt, CONEt2) attached either to the lower rim of calix or to the triazole moieties were synthesized to explore their ion-selectivity for the first time in potentiometric transduction. Plasticized PVC membrane electrodes (ISEs) were fabricated, and their potentiometric selectivities were measured toward a series of mono- and divalent metal ions. Structure-ion-selectivity relationship and the structural requirements of the coordination sphere for selective binding were established. ISEs made of calix[4]arene-bis-triazoles were found generally to exhibit distinct Ag+ selectivity in the order 3 ≈ 4 > 2 > 1, indicating the beneficial effect of the carboxamide or ester groups in the complexing site. In contrast, calix[4]arene-tetratriazole 5 comprised only sp 2 N-donor atoms displayed excellent Cu2+ selectivity over a series of alkali-, alkaline earth- and transition metal ions. A unique feature of the outstanding Ag+ selective electrodes made of 3 and 4 was recognized and suggested their potential application as Na+ ISEs in systems not containing silver ions. Further, the potential use of competitive ESI-MS experiments for screening the binding affinities of ionophores 36 to different metal ions was also demonstrated.  相似文献   

15.
The reactions of N-(2(diphenylphosphino) benzylidene) (phenyl) methanamine, Ph2PPhNHCH2-C5H4N, 1 and N-(2-(diphenylphosphino) (benzylidene) (thiophen-2-yl) methanamine, Ph2PPhNHCH2-C4H3S, 2 with MCl2(cod) and MCl(cod)Me (M = Pd, Pt; cod = 1,5-cyclooctadiene) yield the new complexes [M(Ph2PPhNHCH2-C5H4N)Cl2], M = Pd1a, Pt1b, [M(Ph2PPhNHCH2-C5H4N)ClMe], M = Pd1c, Pt 1d, [M(Ph2PPhNHCH2-C4H3S)Cl2], M = Pd2a, Pt 2b, and [M(Ph2PPhNHCH2-C4H3S)ClMe], M = Pd2c, Pt 2d, respectively. The new compounds were isolated as analytically pure crystalline solids and characterized by 31P-, 1H-NMR, IR spectroscopy, electro spray ionization-mass spectrometry (ESI-MS) and elemental analysis. The representative solid-state molecular structures of the platinum complexes 1b and 2b were determined using single crystal X-ray diffraction analysis and revealed that the complexes exhibit a slightly distorted square-planar geometry. Furthermore, the palladium complexes were tested as potential catalysts in the Heck and Suzuki cross-coupling reactions.  相似文献   

16.
The reactions of [MIII(CN)6]3? (M = Cr or Co) with CuII complexes of a tridentate schiff base [Cu(aemp)Cl] or [Cu(aemp)Ac]2 (Haemp = 2-[(2-amino-ethylimino)-methyl]-phenol) give rise to 1D cyanide-bridged bimetallic coordination polymers [Cu4(aemp)4(H2O)2][Cr(CN)6]Cl (1) and [Cu3(aemp)3(H2O)][Co(CN)6]·2H2O·MeOH (2). In complex 1, the six cyanide ligands of the [Cr(CN)6]3? moiety are involved in bridging, while in complex 2 only five cyanide ligands act as bridges to give a neutral chain. Magnetic studies reveal that complex 1 exhibits intermetallic ferromagnetic coupling, with J = 8.2 cm?1.  相似文献   

17.
2-Propylamino-5-[4-(2-hydroxy-3,5-dichlorobenzylideneamino) phenyl]-1,3,4-thiadiazole, formulated as C18H16Cl2N4OS (I), was synthesized. The crystal and molecular structure of (I) have been determined by 1H-NMR, IR, and X-ray single crystal diffraction. The compound (I) crystallizes in the monoclinic, space group P2(1)/c with unit cell parameters a = 9.0576(2) Å, b = 24.3382(8) Å, c = 9.0585(2) Å, M r = 407.31, V = 1851.13(9) Å3, Z = 4, R 1 = 0.036, and wR 2 = 0.096. Molecular geometry from X-ray experiment of (I) in the ground state has been compared using the density functional method (B3LYP) with 6-31G(d) basis set. To determine conformational flexibility, molecular energy profile of (I) was obtained by semi-empirical (PM3) calculations with respect to selected degree of torsional freedom, which was varied from ?180° to +180° in steps of 10°. The results are indicative that the Schiff base, which contains a thiadiazole ring, prefers to be in E-configuration. In addition, molecular electrostatic potential, frontier molecular orbitals, and natural bond orbitals analysis were performed by the B3LYP/6-31G(d) method.  相似文献   

18.
A mild and simple technique for preparing of 4-benzyl-1-(3-[125I]iodobenzylsulfonyl)piperidine, 4-(3-[125I]iodobenzyl)-1-(benzylsulfonyl)piperazine and their derivatives, as sigma-1 receptor ligands, with relatively high radiochemical yields via nucleophilic substitution reaction by means of isotopic and non-isotopic exchange reactions is described. Some factors affecting the radiochemical yield were commonly studied in presence of acidic medium at elevated temperature. Unfortunately, the radiochemical yields were weak. Some attempts were carried out in presence of polar aprotic solvents to enhance the radiochemical yield. N,N-Dimethylformamide was proved highly efficient for preparing of radioiodinated 4-benzyl-1-(3-iodobenzylsulfonyl)piperidine (4-B-[125I]-IBSP, 70 ± 5.7 %) and 4-(3-iodobenzyl)-1-(benzylsulfonyl)piperazine (4-[125I]-IBBSPz, 72 ± 6.0 %) at moderate temperature (100–105 °C) within 8 h. The specific activities of 4-B-[125I]-IBSP and 4-[125I]-IBBSPz (6,534.2 and 5,927.4 MBq/mmol) were obtained respectively.  相似文献   

19.
In this work, (3,6-bis(2,3-dihydrothieno[3,4-b][1,4]dioxin-5-yl)-9-(4-vinylbenzyl)-9H-carbazole) (EDOTVBCz) comonomer was chemically synthesized and characterized by Fourier transform infrared (FTIR), proton nuclear magnetic resonance, and carbon nuclear magnetic resonance spectroscopy. EDOTVBCz was electrocoated on glassy carbon electrode (GCE) in various initial molar concentrations ([EDOTVBCz]0?=?1.0, 1.5, 2.0, and 3.0) in 0.1 M lithium perchlorate (LiClO4)/acetonitrile (CH3CN). P(EDOTVBCz)/GCE was characterized by cyclic voltammetry, FTIR reflectance-attenuated total reflection spectroscopy, scanning electron microscopy–energy dispersive X-ray analysis, atomic force microscopy, and electrochemical impedance spectroscopy (EIS). EIS was used to determine the capacitive behaviors of modified GCE via Nyquist, Bode magnitude, Bode phase, and admittance plots. The highest low-frequency capacitance value was obtained as C LF?=?~2.35 mF cm?2 for [EDOTVBCz]0?=?3.0 mM. Double-layer capacitance of the polymer/electrolyte system was calculated as C dl?=?~2.78 mF cm?2 for [EDOTVBCz]0?=?1.0 and 3.0 mM. The maximum phase angle was obtained as θ?=?~76.7o for [EDOTVBCz]0?=?1.0, 1.5, 2.0, and 3.0 mM at the frequency of 20.6 Hz. AC impedance spectra of P(EDOTVBCz)/LiClO4/CH3CN was obtained by performing electrical equivalent circuit model of R(Q(R(CR))) with linear Kramers–Kronig test.
Figure
SEM-EDX analysis of P(EDOTVBCz)/CFME EDX point analysis inset: SEM point analysis, [EDOTVBCz]0?=?3 mM. Chronoamperometric method of constant potential at 1.6 V, 300 s in 0.1 M LiClO4/CH3CN  相似文献   

20.
The aim of this work was to synthesize deuterated and tritiated analogues of highly oxidized lupane derivatives known from our group. We selected compounds that previously showed very high cytotoxic activity on multiple cancer cell lines in order to further investigate the mechanism of their action. From starting material (compounds 14), we obtained benzyl platanate (5) and its reaction with deuteromethyltriphenylphosphonium iodide gave deuterated compound 6. Following benzyl deprotection gave free acid 7 and oxidation with SeO2 gave 30-oxo-[29-2H2]lup-20(29)-en-28-oic acid (8), which is one of the most active compounds synthesized in our group to date (IC50 6 μmol/L on CEM cell line). The alkylation of benzyl 2-hydroxy-3-oxolupa-1,20(29)-dien-28-oate (9) with methyliodide or deuteromethyliodide followed by a series of deprotection and hydrogenation steps gave compounds 1014, where 2β-[31-2H3]methoxy-3-oxolupan-20(29)-en-28-oic acid (13) is especially interesting, it showed lower activity on CEM cell line (IC50 10 μmol/L) however, it was very active against Ph1—positive human leukemia BV-173 (IC50 0.91 μmol/L) and against human myelogenous leukemia K562 (IC50 0.52 μmol/L). Selectively labelled [3α-2H] and [3α-3H] methyl 3β-acetoxy-21,22-dioxolup-18-en-28-oates 24, 25 were prepared in three steps by reduction of corresponding 3-oxo derivatives and they showed moderate activity on CEM cell line (IC50 10 μmol/L). In total, 11 labelled compounds (68, 11, 14, 18, 19, 21, 22, 24 and 25) have not been reported before.  相似文献   

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