Curcumin as the OO bidentate ligand in "2 + 1" complexes with the [M(CO)3]+ (M = Re, 99mTc) tricarbonyl core for radiodiagnostic applications.

Abstract

The synthesis and characterization of "2 + 1" complexes of the [M(CO)(3)](+) (M = Re, (99m)Tc) core with the β-diketones acetylacetone (complexes 2, 8) and curcumin (complexes 5, 10 and 6, 11) as bidentate OO ligands, and imidazole or isocyanocyclohexane as monodentate ligands is reported. The complexes were synthesized by reacting the [NEt(4)](2)[Re(CO)(3)Br(3)] precursor with the β-diketone to generate the intermediate aqua complex fac-Re(CO)(3)(OO)(H(2)O) that was isolated and characterized, followed by replacement of the labile water by the monodentate ligand. All complexes were characterized by mass spectrometry, NMR and IR spectroscopies, and elemental analysis. In the case of complex 2, bearing imidazole as the monodentate ligand, X-ray analysis was possible. The chemistry was successfully transferred at (99m)Tc tracer level. The curcumin complexes 5 and 6, as well as their intermediate aqua complex 4, that bear potential for radiopharmaceutical applications due to the wide spectrum of pharmacological activity of curcumin, were successfully tested for selective staining of β-amyloid plaques of Alzheimer's disease. The fact that the complexes maintain the affinity of the mother compound curcumin for β-amyloid plaques prompts for further exploration of their chemistry and biological properties as radioimaging probes.

• Authors: Marina Sagnou, Dimitra Benaki, Charalampos Triantis, Theodoros Tsotakos, Vassilis Psycharis, Catherine P Raptopoulou, Ioannis Pirmettis, Minas Papadopoulos, Maria Pelecanou
• Journal: Inorganic chemistry (Inorg Chem) Vol. 50 Issue 4 Pg. 1295-303 (Feb 21 2011) ISSN: 1520-510X [Electronic] United States
• PMID: 21250638 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Cyclohexanes
• Imidazoles
• Nitriles
• Organometallic Compounds
• Organotechnetium Compounds
• Radiopharmaceuticals
• isocyanocyclohexane
• Rhenium
• Technetium
• Carbon Monoxide
• Curcumin

Topics

• Alzheimer Disease (diagnosis, metabolism)
• Brain (pathology)
• Carbon Monoxide (chemistry)
• Crystallography, X-Ray
• Curcumin (chemistry)
• Cyclohexanes (chemistry)
• Humans
• Imidazoles (chemistry)
• Nitriles (chemistry)
• Organometallic Compounds (chemical synthesis, chemistry)
• Organotechnetium Compounds (chemical synthesis, chemistry)
• Plaque, Amyloid (diagnosis, metabolism)
• Radiopharmaceuticals (chemical synthesis, chemistry)
• Rhenium (chemistry)
• Technetium (chemistry)