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[en] Polymer ligands containing a covalently bonded quinolinone fluorophor and COOH (L1) or COONa (L2) binding sites were synthesized by the reaction of high-molecular-weight poly[styrene-alt-(maleic anhydride)] with 7-amino-4-methylquinolin-2(1H)-one and methanol and subsequent neutralization. The ligand-to-metal energy transfer and ligand binding properties in a series of [Tb(III)-ligand] complexes were investigated by steady-state and time-resolved luminescence spectroscopy in methanol or deuterated methanol. The intensity of the long-lived terbium(III) ion emission at 490, 545, 585 and 620 nm was greatly enhanced upon addition of L1 or L2. Based on the differences in luminescence data obtained for [Tb(III)-L1] and [Tb(III)-L2] complexes, a qualitative model for the interaction of terbium(III) ion with L1 and L2 is put forward. The experimental luminescence decay curves were double-exponential (τ1, τ2) with predominating longer component (rel B1 > 85%) for both [Tb(III)-L1] and [Tb(III)-L2] complexes. About 2.5 or 2 methanol molecules were coordinated to Tb3+ in [Tb(III)-L1] or [Tb(III)-L2] complexes, respectively, whereas ca. 6.5 methanol molecules were coordinated to Tb3+ in methanol. (author)
[en] The first part of the work was to detect antibiotic residues in animal nutriment: chicken, fish, eggs and milk, by methods of screening. The second part covered the development of a new kit for the detection of antibiotic residues. (Author)
[en] Following work done by Professor John McAfee and Mathew Thakur at the MRS Cyclotron Unit a method is available for labelling cells with indium-111 which results in a stable intracellular marker. The method uses indium-111-8 hydroxyquinoline (111In oxine) which is a lipoid soluble complex which goes across the cell membrane and results in the deposition of indium into various subcellular structures. It has been applied to various preparations of white cells, platelets and also malignant cells. Autologous granulocytes have been used to identify inflammatory lesions in 35 patients. By similar means autologous lymphocytes can also be labelled and reinfused. Lymphocytes have been shown in animals to circulate from the blood via the lymphatic system and then returning to the blood once more. The same phenomenon can be seen in man using indium labelled lymphocytes. Lymph nodes become visible at between 12 and 18 hours and recirculation of labelled cells can be shown on the blood activity curves. Certain problems arise concerning cell behaviour after labelling which appear due to irradiation of cells rather than chemical toxicity. (author)
[en] Quinolines are thermally stable and can be used as an excellent n-type semiconducting materials. Since quinolines are also known to be electron acceptor molecules, combination of various electron donor building blocks can be utilized in photonic and electronic organic light-emitting diode (OLED) applications. For example, donor.acceptor systems with phenothiazine (or carbazole) molecules as electron donors and the phenylquinoline group as an electron acceptor provide an efficient approach for the design of new materials exhibiting highly efficient charge-transfer photophysics and electroluminescence in OLEDs. We have described the Friedlander quinoline synthesis between aminobenzophenones and symmetrical diacetyl compounds having phenothiazine, carbazole, biphenyl, and phenyl moieties under solvent-free microwave irradiation in 12.98% isolated yields
[en] 2,2'-[(8-hydroxyquinolin-7-yl)methylazanediyl]diacetic acid (HQMADA) was synthesized via reaction of 8-hydroxyquinoline with iminodiacetic acid in presence of paraformaldehyde with a yield of 27%. The obtained compound was well characterized via different analytical techniques. Labeling of the synthesized compound with technetium-99m in pertechnetate form (99mTcO4-) in the presence of stannous chloride dihydrate was carried out via chelation reaction. The reaction parameters that affect the labeling yield such as HQMADA concentration, stannous chloride dihydrate concentration, pH of the reaction mixture, and reaction time were studied to optimize the labeling conditions. Maximum radiochemical yield of 99mTc-HQMADA complex (91.9%) was obtained by using 1.5 mg HQMADA, 50 μg SnCl2 x 2H2O, pH 8 and 30 min reaction time. Biodistribution studies in mice were carried out in experimentally induced infection in the left thigh using E. coli. 99mTc-HQMADA complex showed higher uptake (T/NT = 5.5 ± 0.3) in the infectious lesion than the commercially available 99mTc-ciprofloxacin (T/NT = 3.8 ± 0.8). Biodistribution studies for 99mTc-HQMADA complex in Albino mice bearing septic and aseptic inflammation models showed that 99mTc-HQMADA complex able to differentiate between septic and aseptic inflammation. (author)
[en] The first total synthesis of Sannanine has been accomplished with an overall 30% yield in a concise manner. The key strategies involve Friedländer quinoline synthesis, demethylation, in situ oxidation and amination process.
Graphical AbstractThe first total synthesis of Sannanine has been accomplished with an overall 30% yield in a concise manner. The key strategies involve Friedländer quinoline synthesis, demethylation, in situ oxidation and amination processes. .
[en] The fluorescence behavior of the N-ethyl isoquinolinium (iso-NEQ) cation in viscous methanol is reported and discussed on the basis of time-resolved fluorescence spectra, polarization measurements and semiempirical calculations. Dual fluorescence results from two nearby excited states (S1 and S2) above 300 nm only at low temperature. The detection of an isoemissive point verifies this two-state model of the emission. We use the numerical self-consistent reaction field (SCRF) to include solute-solvent interactions for the calculations of the absorption transitions of iso-NEQ in methanol. We also involved the so-called supermolecular approach with three methanol molecules to reproduce the absorption transitions. The latter results are in good agreement with our experimental data. (Copyright (c) 1999 Elsevier Science B.V., Amsterdam. All rights reserved.)
[en] A simple and rapid extractive spectrophotometric method for the determination of cadmium in the presence of excess of zinc has been developed using oxine as reagent in n-butanol. (author). 7 refs, 1 fig
[en] We report the synthesis of oxo and sulfido bridged tungsten (V) complexes with 5.7 dichloro-8-hydroxyquinoline, 5.7 dibromo-8-hydroxyquinoline and 5.7 diiodo-8-hydroxyquinoline as ligands. These complexes were identified by the infrared and electronic spectra, magnetic susceptibility measurements and analytical data and assigned the following formulae: W2O3(LL)4,W2O4(LL)2, W2O2S2(LL)2 and W2O3S(LL)2. The very low values of the magnetic moment, suggest an intramolecular metal-metal interactions. 14 refs