Synthesis, structural characterization and study of antioxidant and anti-PrP properties of flavonoids and their rhenium(I)-tricarbonyl complexes.

This study aims at the synthesis and initial biological evaluation of novel rhenium-tricarbonyl complexes of 3,3',4',5,7-pentahydroxyflavone (quercetin), 3,7,4΄-trihydroxyflavone (resokaempferol), 5,7-dihydroxyflavone (chrysin) and 4΄,5,7-trihydroxyflavonone (naringenin) as neuroprotective and anti-PrP agents. Resokaempferol was synthesized from 2,2΄,4-trihydroxychalcone by HO/NaOH. The rhenium-tricarbonyl complexes of the type fac-[Re(CO)(Fl)(sol)] were synthesized by reacting the precursor fac-[Re(CO)(sol)] with an equimolar amount of the flavonoids (Fl) quercetin, resokaempferol, chrysin and naringenin and the solvent (sol) was methanol or water.