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601.
Christiane Blanchard Claude Montginoul Eliane Torreilles Louis Giral 《Journal of heterocyclic chemistry》1981,18(4):841-843
N-Alkylations and N-acylations of 9-acridanones substituted in position 2 or 3 by nitro and methoxy groups are described. Physical characteristics of the new compounds so obtained are given. 相似文献
602.
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606.
607.
Pascale Léon Christiane Garbay-Jaureguiberry Jean-Bernard Le Pecq Bernard P. Roques 《Tetrahedron letters》1985,26(40):4929-4932
The 6-ethyl-10-methoxy-7H-pyrido[4,3-c ]carbazole is synthesized via a novel and convenient method involving the condensation of the 2-lithio-5-methoxyindole with the appropriate alkyl pyridyl ketone. Quaternarization of this compound by means of a rigid bis(ethyl-piperidyl) linking chain leads to a new potential antitumour dimer. 相似文献
608.
Christiane Reifenh?user Klaus G. Heumann 《Fresenius' Journal of Analytical Chemistry》1990,336(7):559-563
Summary A definitive method of isotope dilution mass spectrometry (IDMS) was developed to determine four different iodine species in aquatic systems (iodide, iodate and two organoiodine compounds: one of the organic species is chromatographically elutable from a column filled with an anion exchanger resin, the other one is not). The iodine species were analysed after the isotope dilution step with an enriched 129I spike and after their chromatographic separation. The total iodine concentration was measured after decomposition of organic compounds in the aquatic system by UV irradiation. Different types of natural water samples (river water, water of a pond, moorland lake water) were analysed and important water parameters like pH-value, redox potential, oxygen content and dissolved organic carbon were measured for each of these samples. The total iodine concentration in the different samples differed only slightly in the range of 2–7 g/l. In most of the moorland lake water samples only the two organoiodine species could be detected. In these samples the concentration of iodide and iodate was less than the detection limit of 0.5 g/l and 0.1 g/l, respectively. On the other hand, all four iodine species could be determined in most of the river water samples. Positive correlations were found for the oxygen content of the water samples and the iodate concentration as well as for the redox potential and the anionic organoiodine compound.In memoriam of Dr. I. Linus Barnes who died in January, 1990. Dr. Barnes was senior scientist at the National Institute of Standard and Technology in Gaithersburg, USA. He made numerous outstanding contributions to the field of mass spectrometry and IDMS 相似文献
609.
Dietrich-Buchecker C Colasson B Fujita M Hori A Geum N Sakamoto S Yamaguchi K Sauvage JP 《Journal of the American Chemical Society》2003,125(19):5717-5725
Transition metal-mediated templating and self-assembly have shown powerful potentials for the synthesis of interlocked molecules. These two strategies were combined in designing and preparing a new type of coordination catenanes incorporating Cu(I) and Pd(II) metal centers. The ligand designed here contains a phenanthroline core and pyridine sidearms (compound 1). Using this phenanthroline-pyridine conjugated ligand, two approaches were examined, which were shown to be surprisingly efficient for the catenane synthesis: the entwining route (entwining of two ligands around Cu(I) followed by Pd(II) clipping) and the threading approach (Cu(I)-templated threading of a cyclic ligand on an acyclic ligand followed by the Pd(II) clipping of the second ring). In the former method, stepwise treatment of 1 with Cu(CH(3)CN)(4)PF(6) (templating center) and enPd(NO(3))(2) (assembling center) gives rise to the quantitative formation of CuPd(2) catenane 18. In the latter method, Cu(I) templates the threading of phenanthroline-containing macrocycle 2 on ligand 1, which is followed by Pd(II) clipping to give hetero catenane 20. In both approaches, the formation of catenanes is convincing thanks to the strong templating effect of Cu(I), while the ring closure steps are efficiently furnished by Pd(II)-directed self-assembly. 相似文献
610.
Christiane Cocozza-Thivent 《Probability Theory and Related Fields》1985,70(4):509-523
Summary We consider a system of identical interacting particles moving on the lattice
d
. The rate at which a particle at the site x jumps to the site y is p(y–x)b((x), (y)) where p is an irreducible probability on
d
and b((x), (y)) is an increasing (resp. decreasing) function of the number (x) (resp. (y)) of particles at site x (resp. y). We study the convergence of the system to equilibrium and describe the invariant measures. 相似文献