206877-80-7Relevant academic research and scientific papers
Reaction of ruthenium nitrosyl complexes with superoxide
Metzker, Gustavo,Cardoso, Daniel Rodrigues,Franco, Douglas Wagner
, p. 328 - 332 (2013)
The reaction between the ruthenium nitrosyl complexes trans-[Ru II(NO)L1L2]n+, where L1 = (NH3)4 and L2 = imN, nic, 4-pic and P(OEt)3 or L1/L2 = Hedta, with superoxide (O2-) have been probed in aqueous medium at (25 ± 0.1) °C by UV-Vis, DPV and EPR spectroscopies. The reaction involves one electron transfer from O2- to trans-[Ru II(NO)L1L2]n+ yielding trans-[RuII(H2O)L1L2] n+ and nitric oxide (NO) as main reaction products. Using cytochrome c as a probe for superoxide and a competitive kinetic approach, the apparent bimolecular rate constant for the reaction between trans-[Ru II(NO)L1L2]n+ and O 2- have been determined to be in the range of (6.3 ± 0.5) × 103 (L1 = (NH3) 4; L2 = 4-pic) to (5.8 ± 0.2) × 10 6 (L1 = (NH3)4; L2 = P(OEt)3) M-1 s-1. For L1 = (NH 3)4 and L2 = P(OEt)3 the peroxynitrite formation as a by-product of O2- and NO reaction was detected using tyrosine as a probe monitoring the formation of 3-nitro-tyrosine by HPLC-DAD. These nitrosyl compounds can be activated by superoxide, thus holding radical scavenger potential in vivo, besides being useful to modulate the local NO levels.
