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Diamagnetic nitridotechnetium(V) complexes with tri- and tetradentate azomethine ligands which possess electron withdrawing groups in their periphery can be prepared starting from TcNCl 2 (Ph 3 P) 2 or (in the case of the tetradentate ligands) TcNX 4 − (X = Cl, Br). The products are air stable compounds which have been characterized by elemental analysis, infrared and UV-Vis spectroscopy, NMR and mass spectrometry. The mixed-ligand complex [ N -(2-Ethoxycarbonyl-3-oxo-but-l-en(1)yl)-2-aminophen- olato](triphenylphosphine)nitridotechnetium(V) (C 31 H 28 N 2 O 4 PTc, M r = 622.5) crystallizes monoclinic in the space group C 2/ c . The coordination geometry is a distorted square pyramid with the nitrido ligand at the apex.

(Ph 4 As) 2 [TcN(dto) 2 ] can be prepared starting from TcNCl 4 − or TcNCl 2 (Ph 3 P) 2 . The compound crystallizes in at least two modifications: as well as a triclinic form (S. F. Colmanet and M. F. Mackay, Inorg. Chim. Acta, 147 (1988) 173) a monoclinic one has been found (space group C 2/ c , Z = 4, a = 19.424(3), b = 11.254(2), c = 24.958(3) A, β = 107.68(1)°; R = 0.048). Distances and angles in the complex anions in both modifications are almost identical within experimental error. Oxidation of [TcN(dto) 2 ] 2− by Cl 2 produces the Tc(VI) complex TcNCl 4 − exclusively, whereas during the Br 2 oxidation technetium(VI) intermediates are generated containing mixed Br/dto coordination spheres which can be monitored easily by EPR spectroscopy.

Tetraethylammonium bis(1,1-dicyanoethene-2,2-diselenolato)oxotechnetate(V) has been prepared from Tc(V) gluconate and characterized by single-crystal X-ray structural analysis (R = 0.064). In the complex the technetium atom is centred in an approximate square pyramid in which the four selenium atoms form the basal plane and the oxygen is at the apex. The TcSe distances average 2.471(4) A, while TcO is 1.67(2) A.

TcO4− is reduced by a mixture of phosphine and thiol ligands to yield cationic complexes in which both ligands are coordinated. Polar and lipophilic properties of the products can easily be controlled by variation of either of the ligands. The yields are always high. Potential heart affinity of the compounds was screened by means of the isolated perfused rat heart. Some of the complexes show significant heart uptake and good retention in the myocardial tissue.

Es wird eine Methode zur Synthese von 14CH3Bis(dimethylphosphino)-ethan beschrieben, die von Ethan-1,2-bistris-(hydroxymethyl)-phosphoniumchlorid ausgeht. Durch stufenweise Abspaltung von Hydroxymethylgruppen und nachfolgender Phosphoniumsalzbildung mit Hilfe von [14C]Methyliodid wird nach mehreren Sequenzen das Syntheseziel erreicht. Fur die Radio-DC-Analyse wird ein geeignetes chromatographisches System zur Untersuchung von [14CH3]-Bis(dimethylphosphino)-ethandihydrochlorid und dessen Oxidationsprodukten vorgestellt. A synthetic method for [14CH3bis(dimethylphosphino) -ethane is given starting from the ethane-1,2-bis[tris(hydroxytnethyl)- phosphoniumchloride]. The synthetic goal is reached by a step-by-step separation of hydroxymethyl groups followed by the formation of the phosphonium salt with the aid of [14C] methyliodide after several sequences. An appropriate chromatographic system for the radio-TC-analysis of [14C]-bis(dimethylphosphino)-ethane dihydrochloride and its oxidation products is presented.

Six-coordinated tris(monothio-β-diketonates) of Tc(III) and Re(III) have been synthesized by the reaction of M(III) thiourea complexes with the appropriate monothio-β-diketone ligands in methanol. Characterization of the compounds by IR, UV-Vis, 1H NMR and mass spectroscopy indicates that the ligands coordinate as bidentate. The 1H NMR spectra of the paramagnetic substances are well resolved and the chelate ring protons show a large high-field shift of the Tc complcxes and a low-field shift of the corresponding Re analogues. A complete crystal and molecular structure determination, performed on tris(monothiodibenzoylmethanato)technetium(III), is the first structural characterization of a Tc(III) compound with O and S chelate ligands.

The compositions of different compounds of 99Tc(IV) and hydroxy-ethylidendiphosphonic acid have been evaluated using spectrophotometrical and potentiometric methods. The ligand reacts with K2TcBr6 as well as with TcO4′ and SnCl2 under formation of Tc(OH)3LH3, Tc(OH)3LH2−, TcOOHLH2−, Tc2(OH)4LH33+ Tc2(OH)6LH2, Tc2(OH)8L4− and Tc(OH)x(LHy)2(4-x+8+2y)+ complexes respectively. In account of the minor technetium concentrations in 99mTc-radiopharmaceuticals for skeletal imaging the last mentioned compound may be the major component in such preparations.

A series of 7 indiumdialkyldithiocarbamates (R = ethyl, n-propyl, i-propyl, n-butyl, i-butyl, (CH 2 ) 5 , (CH 2 ) 2 O(CH 2 ) 2 ) has been prepared by reacting InCl 3 with aqueous solutions of the ligands. The products have been investigated at various concentration levels. The properties of the products at the lower concentration levels have been studied by thin-layer chromatography, electrophoresis and by determination of the octanol/water partition. A comparison of the results with the behaviour of the well-characterized tris(dialkyldithiocarbamato)indium(III) complexes is given.

Zusammenfassung Die thermodynamischen Funktionen der Bildungsreaktion Me 3+ aq + CH 3 COO − aq ⇌ ( MeOOCCH 3 ) 2+ aq ΔG, ΔS and ΔH fur die Actiniden und Lanthaniden wurden aus elektrostatischen Ansatzen fur die Ligand-Zentralatom-Wechselwirkung berechnet und mit experimentellen Werten verglichen.

Es wird uber eine kontinuierliche Abtrennung von Jod in verschiedenen Oxydationsstufen aus einer Tellur-127-Matrix durch Ionenaustausch berichtet. Tellurit kann an Zinnformen des KPS-200-Harzes fixiert werden, wahrend Jod im Eluat erscheint. Der Vorlauf enthalt das kurzlebige Kernisomere des Tellur-127.

We report the synthesis and characterization of nitridotechnetium(V) complexes containing triphenylphosphine and tridentate azomethine ligands (I) derived from glycine

The preparation of [ 99m Tc(1,2-bis(dimethylphosphino)ethane) 2 Cl 2 ] + ([ 99m Tc(DMPE) 2 Cl 2 ] + ) for imaging the myocardium is investigated. Starting from Fe(III)- or Fe(II)-DMPE and 99m TcO 4 − different preparation variants are compared. In these reactions either ascorbic acid or DTPA serves as an agent for complexing iron. A simple procedure using lyophilized initial components is represented. Its application yields [ 99m Tc(DMPE) 2 Cl 2 ] + with a radiochemical purity of more than 95%. Organ distribution studies performed in rats emphasize the high myocardial accumulation of this preparation.

After incubation of both serum and HSA solutions with radioactive lanthanide complexes the binding constants of the corresponding lanthanide-protein complexes formed in the protein solutions under physiologic conditions, pH: 7.4, temperature: 310 K, isotonic ionic strength: 0.15 mol/L, were determined. The association constants of the lanthanide-protein complexes formed both in serum and HSA-solutions are equal within the experimental error. In conclusion, serum albumin binding predominates for the radiolanthanides. With the decrease of the ionic radii from 1.034 A (Ce) to 0.858 (Yb) the association constants increased by five orders of magnitude from g K pr = 4.90 (Ce) to 1g K pr = 9.54 (Yb). Further, a serum fractionation with alcohol was carried out to prove that the albumin fraction of serum is responsible for the lanthanide binding in blood.