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101.
Pavot Kristian Juraj Bernát Ján Imrich Tatiana Bušová 《Chemistry of Heterocyclic Compounds》1995,31(10):1204-1207
9-Isothiocyanatoacridines containing a reactive NCS group, together with a biologically active acridine skeleton, were used for the synthesis of new acridine heterocycles. Their reactivity with aliphatic and aromatic amines as well as 15 amino acids was quantified by kinetic measurements. Sodium D-alkyl-N-(9-acridinyl)iminothiocarbonates obtained by addition of sodium alkoxides to the title compounds gave three types of products with organic halogen reagents. The reaction of above iminothiocarbonates with alkyl halides led to the fluorescent S-alkyl derivatives, whereas bromoacetyl bromide and alkyl bromoacetates afforded the 3-(9acridinyl)-1, 3-thiazolidine-2,4-diones and a new heterocycle, spiro[dihydroacridine-9(IOH), 4'-thiazoline], respectively.Department of Organic Chemistry, P. J. Safarik University, 04167 Kosice, Slovak Republic. Published in Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1376–1379, October, 1995. Original article submitted July 1, 1995 相似文献
102.
Dikarev EV Shpanchenko RV Andreini KW Block E Jin J Petrukhina MA 《Inorganic chemistry》2004,43(18):5558-5563
The crystal structure of a new hybrid product comprised of two rigid building blocks, namely dirhodium(II) tetraacetate, [Rh(2)(O(2)CCH(3))(4)] (1), and 2,6-diselenaspiro[3.3]heptane, Se(2)C(5)H(8) (2), has been solved ab initio using laboratory source X-ray powder diffraction (XRPD) data. The rigid body refinement approach has been applied to assist in finding an adequate model and to reduce the number of the refined parameters. Complex [Rh(2)(O(2)CCH(3))(4).mu(2)-Se(2)C(5)H(8)-Se,Se'] (3) conforms to the triclinic unit cell with lattice parameters of a = 8.1357(4), b = 8.7736(4), and c = 15.2183(8) A, alpha = 77.417(3), beta = 88.837(3), and gamma = 69.276(4) degrees, V = 989.66(8) A(3), and Z = 2. The centrosymmetric P space group was selected for calculations. The final values of the reduced wR(p), R(p), and chi(2) were calculated at 0.0579, 0.0433, and 5.95, respectively. The structure of 3 is a one-dimensional zigzag polymer built on axial Rh...Se interactions at 2.632(6) A. The 2,6-diselenaspiro[3.3]heptane ligand acts as a bidentate linker bridging dirhodium units via both selenium atoms. The geometrical parameters of individual groups for rigid body refinement have been obtained from X-ray powder data for dirhodium(II) tetraacetate (1) and from single-crystal X-ray diffraction for diselenium molecule 2. The crystal structures of 1 and 2 are reported here for the first time. For 1 indexing based on XRPD data has resulted in the triclinic unit cell P with lattice parameters of a = 8.3392(7), b = 5.2216(5), and c = 7.5264(6) A, alpha = 95.547(10), beta = 78.101(6), and gamma = 104.714(13) degrees, V = 309.51(5) A(3), and Z = 1. The final values were wR(p) = 0.0452, R(p) = 0.0340, and chi(2) = 1.99. The 1D polymeric motif built on axial Rh.O interactions of the centrosymmetric dirhodium units has been confirmed for the solid-state structure of 1. Compound 2,6-diselenaspiro[3.3]heptane (2) conforms to the monoclinic space group P2(1)/c with the unit cell parameters of a = 5.9123(4), b = 19.6400(13), and c = 5.8877(4) A, beta = 108.5500(10) degrees, V = 648.15(8) A(3), and Z = 4. 相似文献
103.
Knudsen KR Bachmann S Jørgensen KA 《Chemical communications (Cambridge, England)》2003,(20):2602-2603
The half-transamination reaction of alpha-keto esters with pyridoxamine or 4-picolylamine was found to be catalysed by different metal catalysts in organic solvents giving moderate yields and enantioselectivities of up to 37% ee for methyl-3-indole pyruvate. 相似文献
104.
105.
Kristian Torbensen Kristoffer Malmos Dr. Frederic Kanoufi Prof. Dr. Catherine Combellas Dr. Steen U. Pedersen Prof. Dr. Kim Daasbjerg 《Chemphyschem》2012,13(14):3303-3307
Scanning electrochemical microscopy is used to carry out local free‐radical grafting at a gold surface through mild oxidation of an aryl hydrazine. The process can be deliberately controlled by creation of a local pH gradient at the tip. Comparison of the experimental results with simulations shows that the radial expansion of the pH profile in which successful grafting can be accomplished increases with increasing generation time of OH? and with decreasing initial concentration of the grafting precursor. Furthermore, the radial expansion is faster than the nucleation of the grafting process. 相似文献
106.
Ringo Grombe Günter Allmaier Jean Charoud-Got Agnieszka Dudkiewicz Håkan Emteborg Thilo Hofmann Erik Huusfeldt Larsen Angela Lehner Meritxell Llinàs Katrin Loeschner Kristian Mølhave Ruud J. Peters John Seghers Conxita Solans Frank von der Kammer Stephan Wagner Stefan Weigel Thomas P. J. Linsinger 《Accreditation and quality assurance》2015,20(1):3-16
107.
108.
Kristian Helmerson Rani Kishore William D. Phillips Howard H. Weetall 《Applied biochemistry and biotechnology》2001,96(1-3):205-213
We used optical tweezers—optical trapping with focused laser beams—to pull microspheres coated with antigens off of an antibody-coated
surface. Using this technique, we could quantify the force required to separate antigen to antibody bonds. At very low surface
density of antigen, we were able to detect the single antigen to antibody binding. The force required to break the antigen-antibody
bonds and pull the microsphere off the surface was shown to increase monotonically with increasing surface density of antigens.
Using the force determination as a transducer, we were able to detect concentrations of free antigens in solution as small
as 10−15 mol/L in a competitive binding assay. 相似文献
109.
Fang X Wang W Yang L Chandrasekaran K Kristian T Balgley BM Lee CS 《Electrophoresis》2008,29(10):2215-2223
By employing a capillary ITP (CITP)/CZE-based proteomic technology, a total of 1795 distinct mouse Swiss-Prot protein entries (or 1705 nonredundant proteins) are identified from synaptic mitochondria isolated from mouse brain. The ultrahigh resolving power of CITP/CZE is evidenced by the large number of distinct peptide identifications measured from each CITP fraction together with the low peptide fraction overlapping among identified peptides. The degree of peptide overlapping among CITP fractions is even lower than that achieved using combined CIEF/nano-RP LC separations for the analysis of the same mitochondrial sample. When evaluating the protein sequence coverage by the number of distinct peptides mapping to each mitochondrial protein identification, CITP/CZE similarly achieves superior performance with 1041 proteins (58%) having 3 or more distinct peptides, 233 (13%) having 2 distinct peptides, and 521 (29%) having a single distinct peptide. The reproducibility of protein identifications is found to be around 86% by comparing proteins identified from repeated runs of the same mitochondrial sample. The analysis of the mouse mitochondrial proteome by two CITP/CZE runs results in the detection of 2095 distinct mouse Swiss-Prot protein entries (or 1992 nonredundant proteins), corresponding to 59% coverage of the updated Maestro mitochondrial reference set. The collective analysis from combined CITP/CZE and CIEF-based proteomic studies yields the identification of 2191 distinct mitochondrial protein entries (or 2082 nonredundant proteins), corresponding to 76% coverage of the MitoP2-database reference set. 相似文献
110.
Nishiwaki N Rahbek Knudsen K Gothelf KV Jørgensen KA 《Angewandte Chemie (International ed. in English)》2001,40(16):2992-2995
No AbstractSupporting information for this article is available on the WWW under http://www.angewandte.com or from the author. 相似文献