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211.
4-(2-Hydroxy-phenyl)-but-3-en-2-one (1) was prepared via condensation of salicylaldehyde with acetone, and then reaction of the ketone 1 with thiosemicarbazide was accompanied by cyclization to give substituted pyrazole (2). Seven new 5-(2-hydroxy-phenyl)-3-methyl-4,5-dihydropyrazole-1-carbothioamide derivatives (3a–3g) were synthesized by the acylation of 2 and characterized by means of elemental analysis, infrared (IR), and 1H nuclear magnetic resonance (NMR). The compounds 3c, 3d, and 3g showed certain bactericidal activity against E. coli; while compound 3g showed certain bactericidal activity against P. vulgaris.
Translated from Chinese Journal of Applied Chemistry, 2006, 23(12): 1355–1358 [译自: 应用化学] 相似文献
212.
为优化抗倒胺结构。合成了30种化合物,用IR,1HNMR及元素分析确定了结构,并进行了水稻发芽试验及田间试验。 相似文献
213.
214.
A quick and efficient two-step assay for monitoring and screening lipase activity that uses a microtitre plate is described. 相似文献
215.
Castaño-Alvarez M Fernández-Abedul MT Costa-García A 《Analytical and bioanalytical chemistry》2005,382(2):303-310
The use of a gold film in-channel detector combined with a poly(methyl methacrylate) (PMMA) CE microchip has been tested for alkaline phosphatase (AP) enzymatic assays. Tris-borate or Tris-Gly (pH 9.0, 50 mmol L–1) buffer solutions were appropriate as running buffer. Signals for three common AP products: -naphthol, p-nitrophenol, and ascorbic acid, were obtained. They were reproducible (RSD 4.4% for six successive electropherograms corresponding to 5 mmol L–1 -naphthol solution) and the response was dependent on concentration (linear relationship for ascorbic acid solutions between 5 and 20 mmol L–1 concentration). Use of an end-channel gold film electrode was also investigated. If one of the reagents (substrate or enzyme) is included in the running buffer, two different types of enzymatic assay are feasible in less than 3 min. 相似文献
216.
(NEt4)2[WIVO(S2C2(CN)2)2] (1), isolated by reaction of Na2 WO4, Na2S2C2(CN)2 (Na2mnt) in acidified (pH5.5) aqueous medium in the presence of excess of sodium dithionite and NEt4Br, reduces CO2/HCO
3
−
(pH 7.5) to yield HCOO− and (NEt4)2[WVIO2(S2C2(CN)2)2] (2) mimicking tungsten-formate dehydrogenase (W-FDH) activity. (1) reacts with Na2MoO4 in acidic medium to produce [MoIvO(S2C2(CN)2)2]2− implicating the displacement of tungsten by molybdenum from the cofactor complex in W-FDH. 相似文献
217.
A. Costantini F. Arcobello Varlese A. Buri F. Branda 《Journal of Thermal Analysis and Calorimetry》1998,52(3):975-983
The effects on the thermal properties and bioactivity of the substitution of CaO by La2O3, Y2O3 and Al2O3 in a glass of composition CaO·SiO2 were studied and compared. The trivalent metal oxides were all effective in raising the glass transformation and softening
temperatures when they replaced CaO in the glass of composition CaO·SiO2. The experimental results suggest that Al2O3 plays the role of a glass-former, while La2O3 and Y2O3 behave as glass-modifiers. The tendency to devitrify appears to be the lower, the farther the glass composition is from those
of the crystalline phases, owing to the need for diffusion over longer distances, the greater the composition difference.
The substitution with the trivalent metal oxides is detrimental to the bioactivity, which is preserved only in the event of
very small degrees of substitution. The most negative role appears to be played by Al2O3.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
218.
In recent years interest in polyphenols as a nutrient in vegetables and fruits has increased because of polyphenols’ positive
effects on human health. The interest focuses on the sensory properties of polyphenols and their influence on the taste of
fruits and derived products. This article presents the development of a bioanalytical measurement technique enabling the determination
of the total polyphenol content (TPC) of fresh grapes within a few minutes. Furthermore this technique allows the control
of TPC during production processes, e. g. fermentation of wine. 相似文献
219.
Möhrle BP Köhler K Jaehrling J Brock R Gauglitz G 《Analytical and bioanalytical chemistry》2006,384(2):407-413
Reflectometric interference spectroscopy (RIfS) is a label-free, time-resolved technique for detecting interactions of molecules
immobilized on a surface with ligands in solution. Here we show that RIfS also permits the detection of the adhesion of tissue
culture cells to a functionalized surface in a flow system. Interactions of T cells with other leukocytes or epithelial cells
of blood vessels are crucial steps in the regulating immune response and inflammatory reactions. Jurkat T cell leukemia cells
rapidly attached to a transducer functionalized with a monoclonal antibody directed against the T cell receptor (TCR)/CD3
complex, followed by activation-dependent cell spreading. RIfS curves were obtained for the Jurkat derivative JCaM 1.6 (which
lacks the key signaling protein Lck), cells preincubated with cytochalasin D (an inhibitor of actin polymerization), and for
surfaces functionalized with an antibody directed against the coreceptor CD28. These curves differed with respect to the maximum
signal and the initial slope of the increase in optical thickness. The testing of chemical inhibitors, cell surface molecules
and gene products relevant to a key event in T cell immunity illustrates the potential of label-free techniques for the analysis
of activation-dependent cell-surface contacts.
The first two authors contributed equally to this paper 相似文献
220.
Chen HQ Wang L Liu Y Wu WL Liang AN Zhang XL 《Analytical and bioanalytical chemistry》2006,385(8):1457-1461
A new fluorescence method for the detection of proteins with novel composite nanoparticles (CdS/PPA) has been developed. The
composite nanoparticles have been prepared through an in-situ polymerization method under ultrasonic irradiation. The surface
of the composite nanoparticles was covered with functional groups (-COOH). These groups may play a major role in the improving
the water solubility and biocompatibility of the nanoparticles. The composite particles is combined with proteins in NaAc-HCl
buffer solution (pH=1.99), which can result in strong fluorescence, and the response is linearly proportional to the concentration
of proteins. In λem/λex=650 nm/365 nm place (the stoke’ shift is 285 nm), its fluorescent strength reaches the maximum. Under
the optimum conditions, the linear range is 0.10–20.0 μg·ml−1 with the detection limit of 41 ng·ml−1 for HSA, and 0.10–15.0 μg·ml−1 with the detection limit of 35 ng·ml−1 for Human γ-IgG . The method has been applied to the determination of the total protein in human serum samples collected
from the hospital and the results are satisfactory. 相似文献