Schiff base technetium complexes

Schiff bases provide useful mixed donor sets. The carbonyl function of the most frequently used ligands is derived from either 1,3-dicarbonyl compounds or salicylaldehyde. Favourable combinations involve O-, N- and S-donor atoms. A range of technetium and rhenium complexes exist with bi-, tri-, tetra- and pentadentate ligands. The geometry of these complexes depends on the number and type of coordinating atoms as well as on the chain length between the donor atoms in the SchifF-base ligands. 

Other lipophilic cations that have been approved as myocardial perfusion agents include a Tc(III) Tc-teboroxime cryptate, (Cardiotec ), the trans-dioxo technetium(V) bis-phosphine complex, "Tc-tetrofosmin (Myoview ) and the mixed ligand Tc(III) Schiff-base bisphosphine Tc-Q12 complex, Tc-furifosmin (TechneScan) (Figure 3). 

Complexes with Dioximes, Schiff Bases, and Other Nitrogen Ligands Complexes with Monodentate Phosphines and Related Ligands Complexes with Bidentate Phosphine, Arsine, and Related Ligands Complexes with Sulfur Ligands Nitrosyl and Thionitrosyl Complexes VII. Technetium(IV)... 

Dioxime type ligands can be considered as Schiff base bischelates (Deutsch et al. 1978 Bandoli et al. 1986). The first complexes with oxime ligands were described as mono-capped Tc(dioxime)3(//OH)SnCl3 (dioxime = dimethylglyoxime) complexes (Treher et al. 1989). The boronic adducts of technetium oximes - (BATOs) (Fig. 2.1.19) - were well characterized, and some could be used both as myocardial and cerebral perfusion agents. The complexes are neutral technetium is coordinated to three N-bonded dioxime molecules and to one Cl or Br atom in an axial position (seven covalent bonds). 

Bandoli G, Mazzi U, Moresco A, Nicolini M, Refosco F, Tisato F (1986) Technetium complexes containing tridentate and bidentate Schiff base type ligands. In Nicolini M, Bandoli G, Mazzi U (eds) Technetium in chemistry and nuclear medicine 2. Cortina International, Verona, Italy, pp... 

Jones AG, Dionauge GF, Davison A et al (1985) Biological distribution and structure function relationship of hexakis isonitrile Tc(I) complexes (abstract). J Nucl Med All Sci 29 200 Jurisson S, Dancey K, McPartlin M, Tasker P, Deutsch E (1984) Synthesis, characterization, and electrochemical properties of technetium complexes containing both tetradentate Schiff base ligands and monodentate tertiary phopshine ligands single crystal structure of trans-(JV,2V-ethy-lene bis(acetylacetone-iminato)bis(triphenylphos- phine)-technetium(III)-hexafluoro-phosphate. Inorg Chem 23 4743-4744... 

Several technetium(IIl) complexes containing both tetradentate Schiff-base and monodentate tertiary phosphine ligands have been synthesized. [Tcj(acac)2enj (PPh3)2 was obtained by reaction of [TcOCU] with H2(acac)2cn and PPh 3 in methanol ... 

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