TY - GEN A1 - Jung, C. M. A1 - Heintz, A. A1 - Kraus, Werner A1 - Wunderlich, G. A1 - Leibnitz, Peter A1 - Pietzsch, H.-J. A1 - Kropp, J. A1 - Deussen, A. A1 - Spies, H. ED - Marino, N. T1 - Technetium- and Rhenium-Labelled Fatty Acids as Model Compounds for Myocardial Metabolism Imaging N2 - In an attempt to develop new technetium-based radiopharmaceuticals for the non-invasive diagnosis of oxidative myocardial metabolism, rhenium model compounds according to the ‚3+1' mixed ligand approach as well as the organometallic tricarbonyl-design were synthesized. The geometrical impact of different chelates on the integrity of the fatty acid head structure was determined by single crystal X-ray analyses. To evaluate the diagnostic potential of the analogous Technetium-99m compounds, fatty acid complexes of the ‚3+1' mixed ligand type were prepared on n.c.a.-level and studied in the isolated constant-flow-perfused guinea pig heart model; compared to established [123I]Iodine-labelled fatty acid radiotracers, the tested Technetium-99m derivatives showed a specific, however significantly lower myocardial extraction rate. T2 - 6th International Symposium on Technetium in Chemistry and Nuclear Medicine CY - Bressanone, Italy DA - 2002-09-04 KW - Fatty acids KW - Metabolism KW - Myocardial Imaging KW - Rhenium KW - Technetium-99m PY - 2002 UR - http://www.fzd.de/db/!Publications?pSelYear=2002&pLang=en&pNid=0&pSelWithSubmitted=0&pSelSort=TITEL&pSelPublForm=4&pSelPage=2 SN - 88-86281-73-0 N1 - Serientitel: Technetium, rhenium and other metals in chemistry and nuclear medicine – Series title: Technetium, rhenium and other metals in chemistry and nuclear medicine VL - 6 IS - 6 SP - 443 EP - 445 PB - SGEditoriali CY - Padova AN - OPUS4-1999 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Jung, C. M. A1 - Kraus, Werner A1 - Leibnitz, Peter A1 - Pietzsch, H.-J. A1 - Kropp, J. A1 - Spies, H. T1 - Synthesis and First Crystal Structure of Rhenium Complexes derived from omega-Functionalized Fatty Acids as Model Compounds of Technetium Tracers for Myocardial Metabolism Imaging N2 - In an attempt to develop new technetium-based radiopharmaceuticals for the noninvasive diagnosis of myocardial metabolism, we have synthesized three examples of novel metal-containing fatty acid derivatives according to the 3+1 mixed-ligand and the Schiff base/tricarbonyl design. The chelates contain the metal core in the oxidation states +5 and +1, respectively, and are attached to the end-position of a fatty acid chain. The complex formation was accomplished by ligand-exchange reactions with three different rhenium precursors, whereas the inactive rhenium metal was utilized as a surrogate of the technetium radionuclide. The molecular structures of the fatty acid complexes 7, 10 and 14 were determined by single-crystal X-ray diffraction analyses and impressively show a general problem in technetium tracer research, namely the significant structural alterations of bioactive molecules by coordination even to small metal chelates. KW - Rhenium KW - Technetium KW - Fatty acids KW - Drug research KW - Radiopharmaceuticals PY - 2002 U6 - https://doi.org/10.1002/1099-0682(200205)2002:5<1219::AID-EJIC1219>3.0.CO;2-N SN - 1434-1948 SN - 1099-0682 VL - 2002 IS - 5 SP - 1219 EP - 1225 PB - Wiley-VCH Verl. CY - Weinheim AN - OPUS4-1552 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Drews, A. A1 - Pietzsch, H.-J. A1 - Syhre, R. A1 - Seifert, S. A1 - Varnäs, K. A1 - Hall, H. A1 - Halldin, C. A1 - Kraus, Werner A1 - Karlsson, P. T1 - Synthesis and biological evaluation of technetium(III) mixed-ligand complexes with high affinity for the cerebral 5-HT1A receptor and the alpha-1-adrenergic receptor N2 - Tc(III) and Re(III) complexes [M(NS3)(CNR)] (M = Re, 99mTc, NS3 = 2,2?,2?-nitrilotris(ethanethiol), CNR = functionalized isocyanide bearing a derivative of WAY 100635) have been synthesized and characterized. Re was used as Tc surrogate for chemical characterization and in vitro receptor-binding studies. For two representatives subnanomolar affinities for the 5-HT1A as well as for the alpha1-adrenergic receptor were reached. Biodistribution studies in rats of the 99mTc complexes showed brain uptakes between 0.3 and 0.5% ID/organ (5 min p.i.). In vitro autoradiography of one 99mTc representative in sections of post mortem human brain indicate its accumulation in 5-HT1A receptor-rich brain regions. However, addition of the specific 5-HT1A receptor agonist 8-OH-DPAT as well as the alpha1-adrenoceptor antagonist prazosin could not substantially block this tracer accumulation. A preliminary SPET study in a monkey showed negligible brain uptake. KW - 5-HT1A receptor KW - Alpha 1-adrenergic receptor KW - Technetium-99m KW - Rhenium KW - Autoradiography KW - SPET PY - 2002 U6 - https://doi.org/10.1016/S0969-8051(02)00296-2 SN - 0883-2897 VL - 29 IS - 4 SP - 389 EP - 398 PB - Elsevier Science Inc. CY - New York, NY AN - OPUS4-1553 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Heimbold, I. A1 - Drews, A. A1 - Kretzschmar, M. A1 - Varnäs, K. A1 - Hall, H. A1 - Halldin, C. A1 - Syhre, R. A1 - Kraus, Werner A1 - Pietzsch, H.-J. T1 - Synthesis, Biological and Autoradiographic Evaluation of a Novel Tc-99m Radioligand derived from WAY 100635 with High Affinity for the 5-HT1A Receptor and the alpha1-Adrenergic Receptor N2 - This paper reports the synthesis, biological evaluation, in vitro and ex vivo autoradiography of the first Tc-99m ligand with subnanomolar affinity for the 5-HT1A receptor and a remarkably high affinity for the alpha1-adrenergic receptor. The neutral “3+1” mixed-ligand complex combines 4-(6-mercaptohexyl)-1-(2-methoxyphenyl)piperazine as monodentate and 3-(N-methyl)azapentane-1,5-dithiol as tridentate unit with oxotechnetium(V). The analogous rhenium complex was synthesized for complete structural characterization and used in receptor binding assays. In competition experiments both complexes display subnanomolar affinity for the 5-HT1A receptor (IC500.24 nM for Re, 0.13 nM for Tc) but also very high affinities for the alpha1-adrenergic receptor (IC50 0.05 nM for Re, 0.03 nM for Tc). Biodistribution studies show a brain uptake in rat of 0.22% ID five minutes post injection. In vitro autoradiographic studies in rat brain and postmortem human brain indicate accumulation of the Tc-99m complex in brain areas which are rich in 5-HT1A receptors or in alpha1-adrenergic receptors. This in vitro enrichment can be blocked respectively by the 5-HT1A receptor agonist 8-OH-DPAT or by prazosin hydrochloride, an alpha1-adrenergic receptor antagonist. Ex vivo autoradiographic studies in rats show a slight accumulation of the Tc-99m complex in 5-HT1A receptor-rich areas of the brain, which could not be blocked, as well as in regions rich in alpha1-adrenergic receptors, which could be blocked by prazosin hydrochloride. KW - Serotonin-5-HT1A receptor KW - Tc-99m receptor ligand KW - WAY100635 analogue KW - Ligand synthesis KW - In vitro and ex vivo autoradiography KW - Receptor binding assay PY - 2002 U6 - https://doi.org/10.1016/S0969-8051(01)00313-4 SN - 0883-2897 VL - 29 SP - 375 EP - 387 PB - Elsevier Science Inc. CY - New York, NY AN - OPUS4-1554 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Schiller, E. A1 - Kraus, Werner A1 - Reck, Günter A1 - Spies, H. A1 - Pietzsch, H.-J. T1 - [2-Carboxy-2,2',2''-nitrilotris(ethanethiolato)-kappa4N,S,S',S''](triphenyl-phosphine-kappaP)rhenium(III) acetone solvate N2 - The title compound, [Re(C7H12NO2S3)(C18H15P)]·C3H6O, crystallizes from a solution in chloro­form–acetone–cyclo­­hexane with enantiomers disordered equally over each mol­ecular site. Hydrogen bonds between the carbox­yl groups form dimers in the crystal structure. PY - 2005 U6 - https://doi.org/10.1107/S1600536805018660 SN - 1600-5368 VL - 61 IS - 7 SP - m1373 EP - m1375 PB - Munksgaard CY - Copenhagen AN - OPUS4-7613 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Kraus, Werner A1 - Walther, M. A1 - Jung, C. M. A1 - Emmerling, Franziska A1 - Pietzsch, H.-J. T1 - Bromotricarbonyl{15-[2-(methylsulfanyl)ethylsulfanyl]pentadecanoic acid-kappa2S,S'}rhenium(I) N2 - The title compound, [ReBr(C18H36O2S2)(CO)3], was synthesized and characterized as a non-radioactive surrogate of a novel Tc-containing fatty acid derivative prepared according to the tricarbonyl/dithioether design with the objective of developing new Tc-based radiopharmaceuticals for the non-invasive diagnosis of myocardial metabolism. The Re chelate contains the metal in the oxidation state +1 and is attached to the terminal position of a fatty acid. The complex formation was accomplished by a ligand exchange reaction using [NBu4]2[Re(CO)3Br3] as starting material. KW - Fatty acid KW - Tc-compound KW - Radio-pharmaceutical PY - 2006 U6 - https://doi.org/10.1107/S1600536806024081 SN - 1600-5368 VL - 62 IS - 7 SP - m1660 EP - m1662 PB - Munksgaard CY - Copenhagen AN - OPUS4-12529 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Heinrich, T.K. A1 - Kraus, Werner A1 - Pietzsch, H.-J. A1 - Smuda, C. A1 - Spies, H. T1 - Novel Rhenium Chelate System Derived from Dimercaptosuccinic Acid for the Selective Labeling of Biomolecules N2 - This work is part of an effort to develop chelating agents for stable binding and easy conjugation of Re-188 to biologically interesting structures. Starting from the well-known in vivo stability of [188ReO(DMSA)2]-, we want to exploit this coordination system for the design of 188ReO(V) chelates, which are stable toward reoxidation to perrhenate and toward ligand exchange under all conditions of radiopharmaceutical development. Therefore, a new type of tetradentate ligand has been synthesized by bridging two molecules of N,N'-diisobutyl-2,3-dimercaptosuccinamide with N-(3-aminopropyl)propane-1,3-diamine. The resulting stereoisomeric tetrathiolato S4 ligand of composition (iBu)2N(O)C-C(SH)-C(SH)-C(O)NH-(CH2)3-NH-(CH2)3-NHC(O)-C(SH)-C(SH)-C(O)N(iBu)2 forms anionic five-coordinate oxorhenium(V) complexes by a ligand-exchange reaction of NBu4[ReOCl4] in methanol. In the absence of a base, the compounds were isolated as "betaine", [ReO(S4)], with the protonated nitrogen of the bridge serving as an internal "counterion". Two representatives have been fully characterized in both the solid and solution states and found to adopt the expected square-pyramidal coordination geometry. The equatorial plane is formed by four thiolate sulfur atoms, whereas the oxygen occupies the apical position. The orientation of the metal oxo group is exo in relation to the carbamido groups in both isomers. Both complexes are stereoisomeric regarding the junction of the triamine chain. PY - 2005 U6 - https://doi.org/10.1021/ic051148s SN - 0020-1669 SN - 1520-510X VL - 44 IS - 26 SP - 9930 EP - 9937 PB - American Chemical Society CY - Washington, DC AN - OPUS4-12507 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Tisato, F. A1 - Refosco, F. A1 - Porchia, M. A1 - Bolzati, C. A1 - Bandoli, G. A1 - Dolmella, A. A1 - Duatti, A. A1 - Boschi, A. A1 - Jung, C. M. A1 - Pietzsch, H.-J. A1 - Kraus, Werner T1 - The Crucial Role of the Diphosphine Heteroatom X in the Stereochemistry and Stabilization of the Substitution-Inert [M(N)(PXP)]2+ Metal Fragments (M = Tc, Re; PXP = Diphosphine Ligand) N2 - The nature of the heteroatom X incorporated in the five-membered PXP-diphosphine bridging chain was found to play a primary unit role both in the overall stability and in the stereochemical arrangement of nitrido-containing [M(N)(PXP)]2+ metal fragments (M = Tc, Re). Thus, by mixing PXP ligands with labile [Re(N)Cl4]- and Tc(N)Cl2(PPh3)2 nitrido precursors in CH2Cl2/MeOH mixtures, a series of neutral M(N)Cl2(PXP) complexes (M = Tc, 1-5; M = Re, 8, 9) was collected. In the resulting distorted octahedrons, PXP adopted facial or meridional coordination, and combination with halide co-ligands produced three different stereochemical arrangements, that is, fac,cis, mer,cis, and mer,trans, depending primarily on the nature of the diphosphine heteroatom X. When X = NH, mer,cis-Tc(N)Cl2(PNP1), 1, was the only isomer formed. Alternatively, when a tertiary amine nitrogen (X = NR; R = CH3, CH2CH2OCH3) was introduced in the bridging chain, fac,cis-M(N)Cl2(PN(R)P) complexes (M = Tc, 2, 3; M = Re, 8f) were obtained. Isomerization into the mer,cis-Re(N)Cl2(PN(R)P), 8m, species was observed only in the case of rhenium when the tertiary amine group carried the less encumbering methyl substituent. fac,cis-Tc(N)Cl2(PSP), 4f, was isolated in the solid state when X = S, but a mixture of fac,cis-Tc(N)Cl2(PSP) and mer,trans-Tc(N)Cl2(PSP), 4m, isomers was found in equilibrium in the solution state. A similar equilibrium between fac,cis-M(N)Cl2(POP) (M = Tc, 5f; M = Re, 9f) and mer,trans-M(N)Cl2(POP) (M = Tc, 5m; M = Re, 9m) species was detected in POP-containing complexes. The molecular structure of all of these complexes was assessed by means of conventional physicochemical techniques including multinuclear NMR spectroscopy and X-ray diffraction analysis of representative mer,cis-Tc(N)Cl2(PN(H)P), 1, fac,cis-Tc(N)Cl2(PSP), 4f, and mer,cis-Re(N)Cl2(PN(Me)P), 8m, compounds. PY - 2004 U6 - https://doi.org/10.1021/ic049139r SN - 0020-1669 SN - 1520-510X VL - 43 IS - 26 SP - 8617 EP - 8625 PB - American Chemical Society CY - Washington, DC AN - OPUS4-5546 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Mironov, Y.V. A1 - Shestopalov, M.A. A1 - Brylev, K.A. A1 - Yarovoi, S. S. A1 - Romanenko, G.V. A1 - Fedorov, V.E. A1 - Spies, H. A1 - Pietzsch, H.-J. A1 - Stephan, H. A1 - Geipel, G. A1 - Bernhard, G. A1 - Kraus, Werner T1 - [Re6Q7O(3,5-Me2PzH)6]Br2.3,5-Me2PzH (Q = S, Se) - New Octahedral Rhenium Cluster Complexes with Organic Ligands: Original Synthetic Approach and Unexpected Ligand Exchange in the Cluster Core KW - Rhenium KW - Cluster compounds KW - Ligand exchange KW - Organic ligands KW - Structure elucidation KW - Laser fluorescence spectroscopy PY - 2005 SN - 1434-1948 SN - 1099-0682 SP - 657 EP - 661 PB - Wiley-VCH Verl. CY - Weinheim AN - OPUS4-7039 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Emmerling, Franziska A1 - Kraus, Werner A1 - Noll, B. A1 - Noll, S. A1 - Pietzsch, H.-J. T1 - Two mononuclear Tc complexes: [2,2'-(3-phenylpropylimino)- and [2,2'-(propylimino)bis(ethanethiolato)](4-methoxybenzenethiolato)-oxidotechnate(V) PY - 2007 U6 - https://doi.org/10.1107/S0108270107052870 SN - 0108-2701 SN - 1600-5759 VL - 63 IS - 12 SP - m579 EP - m582 PB - Blackwell Publ. CY - Oxford AN - OPUS4-16283 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -