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51.
Károlyi BI Bösze S Orbán E Sohár P Drahos L Gál E Csámpai A 《Molecules (Basel, Switzerland)》2012,17(3):2316-2329
A series of novel functionalized mono-, bis- and tris-(S)-{[(2S,4R,8R)-8-ethyl-quinuclidin-2-yl](6-methoxyquinolin-4-yl)}methanamines including ferrocene-containing derivatives was obtained by the reaction of the precursor amine with a variety of acylation agents. Their in vitro antitumor activity was investigated against human leukemia (HL-60), human neuroblastoma (SH-SY5Y), human hepatoma (HepG2) and human breast cancer (MCF-7) cells by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT)-assay and the 50% inhibitory concentration (IC(50)) values were determined. Our data indicate that the precursor amine has no antitumor activity in vitro, but the bis-methanamines with ureido-, thioureido and amide-type linkers display attractive in vitro cytotoxicity and cytostatic effects on HL-60, HepG2, MCF-7 and SH-SY5Y cells. Besides 1H- and 13C-NMR methods the structures of the new model compounds were also studied by DFT calculations. 相似文献
52.
ortho-Nitrophenyl-substituted condensed 1,3-benzothiazines proved to be a useful core unit in indole syntheses under non-reductive conditions. Thus, the treatment of ortho-nitro-2-aryl-2a-chloro-4H-azeto[2,1-b][1,3]benzothiazin-1-ones with sodium methoxide in methanol provided indolo-1,4-benzothiazepines via a novel rearrangement. Through the sulfur extrusion reaction of indolo[2,3-b][1,4]benzothiazepines, further alkaloid-type indole derivatives, indolo[3,2-c]isoquinolines, were obtained. The structures of the new ring systems were determined by means of NMR spectroscopy. 相似文献
53.
The influence of the indenter shapes and various parameters on the magnitude of the capillary force is studied on the basis of models describing the wet adhesion of indenters and substrates joined by liquid bridges. In the former, we consider several shapes, such as conical, spherical and truncated conical one with a spherical end. In the latter, the effects of the contact angle, the radius of the wetting circle, the volume of the liquid bridge, the environmental humidity, the gap between the indenter and the substrate, the conical angle, the radius of the spherical indenter, the opening angle of the spherical end in the truncated conical indenter are included. The meniscus of the bridge is described using a circular approximation, which is reasonable under some conditions. Different dependences of the capillary force on the indenter shapes and the geometric parameters are observed. The results can be applicable to the micro- and nano-indentation experiments. It shows that the measured hardness is underestimated due to the effect of the capillary force. 相似文献
54.
In this paper, by capturing the atomic information and reflecting the behaviour governed by the nonlinear potential function,
an analytical molecular mechanics approach is proposed. A constitutive relation for single-walled carbon nanotubes (SWCNT’s)
is established to describe the nonlinear stress-strain curve of SWCNT’s and to predict both the elastic properties and breaking
strain of SWCNT’s during tensile deformation. An analysis based on the virtual internal bond (VIB) model proposed by P. Zhang
et al. is also presented for comparison. The results indicate that the proposed molecular mechanics approach is indeed an
acceptable analytical method for analyzing the mechanical behavior of SWCNT’s.
The project supported by the National Natural Science Foundation of China (10121202, 90305015 and 10328203), the Key Grant
Project of Chinese Ministry of Education (0306) and the Research Grants Council of the Hong Kong Special Administrative Region,
China (HKU 7195/04E). 相似文献
55.
Gábor Bernáth Ferenc Fülöp Alajos Kálmán Gyula Argay Pál Sohár István Pelczer 《Tetrahedron》1984,40(18):3587-3593
The rapid, spontaneous epimerization occurring at the C(2) chirality centre of a new diastereomeric (r-4,c-2,c-5)-2-(p-nitrophenyl)-3-methyl-4,5-tetramethylenetetrahydro-1,3-oxazine led to the conclusion that the configuration at C(2) of the bicyclic 1,3-oxazines formed by the cyclization of alicyclic 1,3-aminoalcohols with aldehydes is determined by the dominant conformation of the product. The first X-ray diffraction evidence is given for the N-outside conformation of compounds of this type. 相似文献
56.
57.
58.
Pál?SohárEmail author Antal?Csámpai Gábor?Magyarfalvi Angela E.?Szabó Géza?Stájer 《Monatshefte für Chemie / Chemical Monthly》2004,135(12):1519-1527
Summary. t-2-Benzoyl-t-4-phenylcyclohexane-r-1-carboxylic acid reacts with hydrazine to give the saturated 1,7-diphenyl-trans-phthalazin-4(3H)-one. The reaction of the acid with ethylenediamine yields diastereomeric trans-imidazo[2,3-a]isoindoles, which differ in their C-1 configuration. The cyclizations of the acid with cis-2-aminocyclohexane- or 4-cyclohexenemethanol result in trans-isoindolo[2,1-a][3,1]benzoxazines, while in its reactions with the analogous di-endo- and di-exo-norbornane- and -norborneneamino alcohols, the acid gives methylene-bridged isomeric di-endo-norbornanes or a norbornene derivative; the corresponding diastereomeric di-exo derivatives have also been prepared. After isolation, the structures were established by means of 1H and 13C NMR spectroscopy, with application of DIFFNOE, DEPT, HMQC, HMBC, and 2D-COSY techniques. 相似文献
59.
Márta?Palkó Elvira?Sándor Pál?Sohár Ferenc?Fül?pEmail author 《Monatshefte für Chemie / Chemical Monthly》2005,136(12):2051-2058
Summary. All-endo-3-amino-5-hydroxybicyclo[2.2.1]heptane-2-carboxylic acid and two epimers of 3-amino-6-hydroxybicyclo[2.2.1]heptane-2-carboxylic
acid were prepared via 1,3-oxazine or γ-lactone intermediates by the stereoselective functionalization of endo-3-aminobicyclo[2.2.1]hept-5-ene-2-carboxylic acid derivatives. Their structures were proved by IR and NMR spectroscopy, with
the use of HMQC, HMBC, DEPT, and DIFFNOE techniques. 相似文献
60.
Chemiluminescence sequential injection immunoassay for vitellogenin using magnetic microbeads 总被引:2,自引:0,他引:2
A rapid and sensitive immunoassay for the determination of carp vitellogenin (Vg) is described. The method involves a sequential injection analysis (SIA) system equipped with a chemiluminescence detector and a samarium-cobalt magnet. An anti-Vg monoclonal antibody, immobilized on magnetic beads, was used as a solid support for the immunoassay. The introduction, trapping and release of the magnetic beads in the flow cell were controlled by a samarium-cobalt magnet and the flow of the carrier solution. The immunoassay was based on a sandwich immunoreaction of anti-Vg monoclonal antibody (primary antibody) on the magnetic beads, Vg, and the anti-Vg antibody labeled with horseradish peroxidase (HRP) (secondary antibody), and was based on a subsequent chemiluminescence reaction of HRP with hydrogen peroxide and p-iodophenol, in a luminol solution. The magnetic beads to which the primary antibody was immobilized were prepared by coupling the primary antibody with the magnetic beads after an agarose-layer on the surface of the magnetic beads was epoxidized. The primary antibody-immobilized magnetic beads were introduced, and trapped in the flow cell equipped with the samarium-cobalt magnet, a Vg sample solution, an HRP-labeled secondary antibody solution and the luminol solution were sequentially introduced into the flow cell based on an SIA programmed sequence. Chemiluminescence emission was monitored by means of a photomultiplier located at the upper side of the flow cell. The optimal incubation times both for the first and second immunoreactions were determined to be 20 min. A concave calibration curve was obtained between Vg concentration and chemiluminescence intensity when various concentrations of standard Vg samples (2–100 ng mL−1) were applied to the SIA system under optimal conditions. In spite of a narrow working range, the lower detection limit of the immunoassay was about 2 ng mL−1. 相似文献