The Chemistry of Transition Metal Complexes Containing Catechol and Semiquinone Ligands

Biological studies of a new class of technetium complexes: the hexakis(alkylisonitrile)technetium(I) cations

Structural survey of technetium complexes

Overview of transition metal and lanthanide complexes as diagnostic tools

Technetium-99m (99mTc) mercaptoacetyltriglycine: update on the new 99mTc renal tubular function agent.

The /sup 99/Tc NMR parameters of a number of Tc(VII) and one Tc(V) species have been determined. The anion TcO/sub 4//sup -/ (..xi.. = 22.508 311 MHz in H/sub 2/O) was chosen as the standard for /sup 99/Tc NMR spectroscopy. A /sup 99/Tc-/sup 17/O coupling constant of 131.4 Hz was obtained from a /sup 17/O- and /sup 18/O-enriched sample of TcO/sub 4//sup -/ whose /sup 99/Tc spectrum also showed an isotopic shift of 0.22 ppm/mass number arising from a statistical distribution of /sup 16/O//sup 17/O//sup 18/O isotopic isomers. Technetium-99 and proton NMR provided definitive proof for the existence of the stereochemically nonrigid TcH/sub 9//sup 2 -/ anion. Both TcO/sub 3/F and the novel TcO/sub 3//sup +/ cation were synthesized and characterized by /sup 99/Tc, /sup 17/O, and /sup 19/F NMR spectroscopy. Preliminary results on two new technetium(VII) oxyfluorides tentatively identified as F/sub 2/O/sub 2/TcOTcO/sub 2/F/sub 2/ and TcO/sub 2/F/sub 3/ are also reported. The diagmagnetic d/sup 2/ anion, TcO/sub 2/(CN)/sub 4//sup 3 -/, represents the most deshielded /sup 99/Tc environment encountered in the present study.

Chemical applications of technetium-99 NMR spectroscopy: preparation of novel technetium(VII) species and their characterization by multinuclear NMR spectroscopy

Studies of the anionic coordination complex /sup 99/Tc-oxo(N,N'-ethylene-bis(2-mercaptoacetimido))technetate(V) ((TcO(ema))-) are described. Syntheses performed both at carrier levels (10(-5)M) and with no carrier added (less than 10(-8)M) indicate that the complex is formed virtually quantitatively from pertechnetateion over this range. Tissue distributions in normal rats are similar at both concentations up to one hour after administration. It has been shown--using a combination of high-pressure liquid chromatography and field-desorption mass spectrometry--that the anion is excreted unchanged into both urine and bile. The effectiveness of this N2S2 donor set in sequestering /sup 99//sup m/Tc, and the in vivo stability of the reslting complex, suggest that modified chelates of this structural classcould provide a series of useful diagnostic agents.

https://jnm.snmjournals.org/content/jnumed/23/9/801.full.pdf

Chemical and In Vivo Studies of the Anion oxo[N,N′-ethylenebis(2-mercaptoacetimido)]Technetate(V)

Reactions of metals with vitamins. I. Crystal and molecular structure of thiaminium tetrachlorocadmate monohydrate.

1-Oxo-2,3,6-(D-penicillaminato-N,S,O)-4,5-(D-penicillaminato-N,S) technetium (V), TcO (C/sub 5/H/sub 9/NO/sub 2/S)(C/sub 5/H/sub 10/NO/sub 2/S), has been obtained as orthorhombic crystals: P2/sub 1/2/sub 1/2/sub 1/; a = 21.878 (5) A, b = 11.711 (2) A, c = 5.924 (1) A; Z = 4. Data were collected with Mo K..cap alpha.. radiation and a Syntex P2/sub 1/ diffractometer. The crystal structure was solved by standard methods and refined to R/sub 1/ = 0.0592 and R/sub 2/ = 0.0439 on the basis of 3401 independent reflections. The technetium is six-coordinate, being bonded to oxygen (Tc-O = 1.657 (4) A), the S, N, and O atoms of a D-penicillamine dianion deprotonated at S and O, and to the S and N atoms of a D-penicillamine anion deprotonated at S. The second Tc-O distance is longer (2.214 (4) A), comparable to the Tc-N distances (2.185 (5), 2.209 (6) A). Tc-S distances are normal (2.283 (2), 2.296 (2) A). The molecules are strongly hydrogen bonded from carboxylic acid to carboxylate into a helical chain in the crystal. NMR, vibrational, and electronic spectra are reported.

Kenneth J. Franklin

Papers

Chemical applications of technetium-99 NMR spectroscopy: preparation of novel technetium(VII) species and their characterization by multinuclear NMR spectroscopy

Chemical and In Vivo Studies of the Anion oxo[N,N′-ethylenebis(2-mercaptoacetimido)]Technetate(V)

Reactions of metals with vitamins. I. Crystal and molecular structure of thiaminium tetrachlorocadmate monohydrate.

Preparation, spectroscopic properties, and structure of 1-oxo-2,3,6-(D-penicillaminato-N,S,O)-4,5-(D-penicillaminato-N,S)technetium(V)

Synthesis and characterization of complexes containing the bis(1, 2-diolato)-oxotechnetium(V) core