Nickel-diflunisal complexes: synthesis, characterization, in vitro antioxidant activity and interaction with DNA and albumins

Ruthenium–arene complexes with NSAIDs: synthesis, characterization and bioactivity

“…Considering the structural factors present in complexes 1-4, it seems that the complexes bearing Z 6 -p-cymene ligands (1 and 2) show higher DNA-affinity than their analogues bearing Z 6 -toluene ligands (3 and 4); also, the complexes bearing mefenamato ligands (2 and 4) are better are within the range found for other metal-NSAID complexes. 17,22,[29][30][31][32][33][65][66][67][68][69] Further, the K b constants are similar to or higher than that of the classical intercalator EB (1.23 Â 10 5 M À1 ) as calculated by Dimitrakopoulou et al 78 The interaction of complexes 1-4 with CT DNA was also monitored via DNA-viscosity measurements in the presence of increasing amounts of the complexes. As is known, the relative DNA-viscosity (Z/Z 0 ) is sensitive to relative DNA-length changes (L/L 0 ) occurring in the presence of a DNA-binder because they are correlated by the equation L/L 0 = (Z/Z 0 ) 1/3 .…”

“…In general, complexes 1-4 are better radical scavengers than the corresponding free NSAIDs Hindo and Hmef, suggesting that their coordination to Ru(II) results in enhanced scavenging activity. In comparison with reported metal-NSAID analogues, 17,22,[29][30][31][32][33][65][66][67][68][69] the present complexes 1-4 are significantly active DPPH-, ABTSand hydroxyl-scavengers and LOX-inhibitors. Although the number of the present compounds is rather low to clarify the structural factors that lead to enhanced antioxidant activity, we suggest that the complexes bearing indomethacin and/or p-cymene are the most potent compounds; as a result, complex 1 was found to be the most active compound.…”

“…The K constants of complexes 1-4 are all relatively high, similar to their respective free NSAIDs, and are in the range of the values calculated for metal-NSAID complexes. 17,22,[29][30][31][32][33][65][66][67][68][69] Among the present complexes, complexes 4 and 1 bear the highest K constants for HSA and BSA, respectively. Considering the structural factors present in complexes 1-4, it seems that complexes 1 and 2 bearing Z 6 -p-cymene ligands show higher binding activity for BSA than their analogues 3 and 4 bearing Z 6 -toluene ligands.…”

“…Furthermore, the complexes are more active scavengers of hydroxyl and ABTS radicals than of DPPH radicals; this scavenging selectivity for hydroxyl and ABTS radicals has been previously reported in the literature, [70][71][72] especially for metal-NSAID complexes. 17,22,[29][30][31][32][33][65][66][67][68][69] Interaction with biomolecules Interaction of the complexes with albumins. The most important role of the serum albumins (SAs) is the transportation of ions and drugs towards their biological targets, i.e.…”

“…The derived k q constants for complexes 1-4 are within the range found for a series of metal-complexes bearing NSAIDs as ligands. 17,22,[29][30][31][32][33][65][66][67][68][69] The SA-binding constants (K) of the complexes have been determined (Table 3) from the corresponding Scatchard plots (Fig. S11 and S12, ESI †) and the Scatchard equation (eqn (S4), ESI †).…”