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961.
B. Venkateswara Reddy K. V. N. Suresh Reddy J. Sreeramulu G. V. Kanumula 《Chromatographia》2007,66(1-2):111-114
A rapid, specific reversed phase HPLC method has been developed for simultaneous determination of olanzapine and fluoxetine
in their formulations. Chromatographic separation of these two pharmaceuticals was carried out on an Inertsil C18 reversed phase column (150 mm × 4.6 mm, 5 μm) with a 40:30:30 (v/v/v) mixture of 9.5 mM sodium dihydrogen phosphate (pH adjusted to 6.8 ± 0.1 with triethylamine), acetonitrile and methanol as
mobile phase. The flow rate 1.2 mL min−1 and the analytes are monitored at 225 nm. Paroxetine was used as internal standard. The assay results were linear from 25
to 75 μg mL−1 for olanzapine (r
2 ≥ 0.995) and 100–300 μg mL−1 for fluoxetine (r
2 ≥ 0.995), showed intra- and inter-day precision less than 1.0%, and accuracy of 97.7–99.1% and 97.9–99.0%. LOQ was 0.005
and 0.001 μg mL−1 for olanzapine and fluoxetine, respectively. Separation was complete in less than 10 min. Validation of the method showed
it to be robust, precise, accurate and linear over the range of analysis. 相似文献
962.
[structures: see text] A range of cis-fused hexahydro-1-benzofuran-3(2H)-one or tetrahydro-2H-cyclopenta[b]furan-3(3aH)-one ring systems was synthesized by the rhodium(II) acetate catalyzed reaction of alpha-diazo carbonyl compounds in the presence of various oxygen, nitrogen, and sulfur nucleophiles. A double-nucleophilic addition was possible by using an excess of alpha-diazo ketone. These reactions proceeded with complete diastereoselectivity, and the stereochemistry was confirmed by the single-crystal X-ray analysis. This process discloses the first example of tandem cyclization-nucleophilic addition reaction. 相似文献
963.
The synthesis and anion binding properties of new ruthenium(II) and cobalt(II) phenanthroline complexes, containing two amide
subunits are described. Evidence for anion binding in dimethyl sulfoxide (DMSO) solution was obtained from u.v.–vis titration
experiments. Results indicated that these receptors showed strong affinity for F− and AcO−, and showed weak affinity for OH− and H2PO
4
−
, and showed no affinity for Cl−, Br−, I−. These receptors interacted with various anions examined through hydrogen-bond formation. 相似文献
964.
Jingjing Xu Yidong Lu Baohong Liu Chunhe Xu Jilie Kong 《Journal of Solid State Electrochemistry》2007,11(12):1689-1695
An ultrathin, ordered, and packed protein film, consisting of the 2-mercaptoacetic acid (MAA), polydimethyldiallylammonium
chloride (PDDA), and wild-type (WT) photosynthetic reaction center (RC; termed as WT-RC) or its pheophytin (Phe)-replaced
counterpart (termed as Phe-RC), was fabricated by self-assembling technique onto gold electrode for facilitating the electron
transfer (ET) between RC and the electrode surface. Near-infrared (NIR)-visible (Vis) absorption and fluorescence (FL) emission
spectra revealed the influence of pigment substitution on the cofactors arrangement and excitation relaxation of the proteins,
respectively. Square wave voltammetry (SWV) and photoelectric tests were employed to systematically address the differences
between the WT-RC films and mutant ones on the direct and photo-induced ET. The electrochemical results demonstrated that
ET initiated by the oxidation of the primary donor (P) was obviously slowed down, and the formed P+ had more population as well as more positive redox potential in the Phe-RC films compared with those in the WT ones. The
photoelectrochemical results displayed the dramatically enhanced photoelectric performances of the mutant ones, further suggesting
the slow-down formation of final charge-separated state in Phe-RC. The functionalized protein films introduced in this paper
provided an efficient approach to sensitively probe the redox cofactors and ET differences resulting from only minor changes
in pigment arrangement in the pigment–protein complex. The favored ET process observed for the membrane proteins RC was potentially
valuable for a deep understanding of the multi-step biological ET process and development of versatile bioelectronic devices. 相似文献
965.
M. Blaauw I. H. Degenaar J. J. M. de Goeij 《Journal of Radioanalytical and Nuclear Chemistry》2007,271(3):765-770
In order to correct for neutron self-shielding in large-sample prompt gamma NAA, a method has been developed to determine
the macroscopic scattering and absorption cross sections, i.e., Σ
a and Σ
s, using four Cu flux monitors placed around the sample. With Monte Carlo computations, the neutron densities throughout the
sample and the resulting and the corresponding self-shielding factor as calculated from the Σ
a and Σ
s as obtained through the Cu monitors were compared to the true values. The derived Σ
a and Σ
s were found to be sufficiently accurate as long as Σ
t = Σ
a + Σ
s was less than 0.6 cm−1 and Σ
s/Σ
t was greater than 0.1. 相似文献
966.
J. Kaloustian Paulette Lechene De La Porte T. El-Moselhy H. Lafont H. Portugal 《Journal of Thermal Analysis and Calorimetry》2005,82(2):331-338
Summary Cholesterol constitutes the major component of most gallstones. It was identified and determined in gallstones by thermal
analysis technique (DSC and TG-DTA), mainly by the use of the melting temperature (Tonset=145°C and Tmax=149°C) and by DTG peak decomposition (Tmax=364°C). Cholesterol anhydrous (ChA), which showed endothermic polymorphic peak, Tmax=40°C, without mass loss, was differentiated from cholesterol monohydrate (ChH), which showed a broad endothermic peak, Tmax=59°C, attributed to loss of water of crystallization (theoretical 4.45%). Morphological studies of gallstones were performed
by optical microscopy and scanning electron microscopy (SEM). The stones consisted of a pigmented core with a variably-sized
irregular central cavity, surrounded by a radially arranged deposits of plate-like ChH. The outer part of the stones showed
ChA crystal arborescences. X-ray microanalysis gave a typical spectrum rich in C and O, and in some instances the presence
of P, which was attributed to the presence of phospholipids. CaCO3 was easily characterized by TG with the use of DTG decomposition peak at 674°C. 相似文献
967.
968.
The ab initio calculation of the title compound was carried out at HF as well as DFT level of theory. The full geometry optimization of the ligand was carried out using 6-31G(d) basis set. The results obtained were correlated with the single crystal X-ray data, also reported in this paper, shows close resemblance between these two. The influence of electron correlation effects also was studied by carrying out geometry optimization at the MP2 level. The attempts were also made to ascertain the most stable tautomer of the said compound. 相似文献
969.
In this paper, zinc tetraaminophthalocyanine (Zn-APc) was immobilized on cellulosic fiber by covalent bond to obtain a novel cellulosic fiber supported metallophthalocyanine, named Zn-TDTAPc-F. At pH 11, upon visible light irradiation for 6 h in the presence of O2, Zn-TDTAPc-F was found to be highly effective for the degradation of phenol in aqueous solution, and the degradation rate of phenol was more than 95%. HPLC was used to confirm formic acid, fumaric acid and maleic acid as its main degradation products. 相似文献
970.
A.A.Leslie Gunatilaka Subramaniam Sotheeswaran H.T.Badra Sriyani Eric S. Waight 《Tetrahedron letters》1982,23(29):2987-2990
Hermonionic acid and its decarboxylated product have been isolated from . 13C NMR spectral and chemical evidence indicate that hermonionic acid is 2-0-[2-(3-methylbut-2-enyl)-3-methoxy- 4-hydroxy-5-(3,7-dimethylocta-2,6-dienyl]-4-methoxy-5-(3-methylbut-2-enyl-6-hydroxybenzoic acid. The previously assigned dienone structure for this acid is incorrect. 相似文献