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41.
MarcS. Robillard BartA.J. Jansen Martin Lochner Herv Geneste Yi Li Jaap Brouwer Manfred Hesse Jan Reedijk 《Helvetica chimica acta》2001,84(10):3023-3030
The synthesis of three bis[(tert‐butoxy)carbonyl]‐protected (tetramine)dichloroplatinum complexes 2a – c of formula cis‐[PtCl2(LL)] and of their cationic deprotected analogs 3a – c and their evaluation with respect to in vitro cytotoxicity, intramolecular stability, DNA binding, and cellular uptake is reported. The synthesis comprises the complexation of K2[PtCl4] with di‐N‐protected tetramines 1a – c to give 2a – c and subsequent acidolysis, yielding 3a – c . The cytotoxicity of the complexes is in direct relation to the length of the polyamine. Complexes 3a – c display a significant higher affinity for CT DNA as well as for cellular DNA in A2780 cells than cisplatin. 相似文献
42.
Kalina Kostova Annalaura Lorenzi-Riatsch Yoshihiko Nakashita Manfred Hesse 《Helvetica chimica acta》1982,65(1):249-251
Synthesis of Macrocyclic Lactones by Ring Enlargement Reaction Treatment of 3-(1-nitro-2-oxocyclohexyl)propanal ( 1 ) prepared by Michael addition of 2-nitrocyclohexanon and acrylaldehyde with methyltri (2-propoxy)tita-nium yielded a mixture of 2 and 3 which was converted into 6-nitro-9-decanolide ( 4 ). 相似文献
43.
Andrea Schfer Berthold Fischer Henning Paul Ren Bosshard Manfred Hesse Max Viscontinif 《Helvetica chimica acta》1992,75(6):1955-1964
This paper marks the first reported detection of radical cations by Electrospray-Ionization Mass Spectrometry (ESI-MS). Electron Spin Resonance (ESR) measurements have proven that the detected radical cation existed already in solution and has not been generated by the electrospray ionization technique. However, we observed that the radical cation can be generated by changes in the ionization conditions. A molar mixture of 2-amino-5,6,7,8-tetrahydro-5-methylpterin-4(4H)-one dihydrochloride ( = 5,6,7,8-tetrahydro-N(5)-methylpterin-2 HCl, N(5)-MTHP-2 HCl), and tris(pentane-2,4-dionato)iron(III) in MeCN at pH 2–3 leads to the formation of a [bis(pentane-2,4-dionato)(2-amino-5,6,7,8-tetrahydro-5-methylpteridin-4 (4H)-one)]iron complex ( = [bis(pentane-2,4-dionato) (5,6,7,8-tetrahydro-N(5)-methylpteridin)]iron complex) which can be detected by ESI-MS. The results suggest that this complex might be an FeII radical cation, which could possibly be a suitable model complex for the active center of the phenylalanine hydroxylase. In the same solution, the stable radical cation of N(5)-MTHP is identified by ESI-MS and ESR. 相似文献
44.
Lübbers R. Pleines M. Hesse H.-J. Wortmann G. Grünsteudel H.F. Rüffer R. Leupold O. Zukrowski J. 《Hyperfine Interactions》1999,120(1-8):49-58
The nuclear forward scattering (NFS) of synchrotron radiation is especially suited for probing magnetism at very high pressure,
here in the Mbar range, by the nuclear resonances of 57Fe and 151Eu. We report on high pressure (h.p.) NFS studies with the 14.4 keV transition of 57Fe on magnetic RFe2 Laves phases of cubic C15 structure (YFe2, GdFe2) and hexagonal C14 structure (ScFe2, TiFe2) at pressures up to 100 GPa (=1 Mbar). We present also h.p. NFS studies performed with the 21.5 keV resonance of 151Eu, probing the magnetism in the CsCl-type h.p. phase of EuTe.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
45.
A simple expression for the buffer index of a solution containing a weak polyprotic acid is derived and presented. 相似文献
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Pulsed laser action from CS2: O2 is investigated. Numerical calculations of the pulse shapes of a large number of vibrational- rotational transitions are compared with experiments. The computations show that rotational relaxation determines to a wide extent the spectral and temporal output of the laser. 相似文献
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