Antibacterial studies, DNA oxidative cleavage, and crystal structures of Cu(II) and Co(II) complexes with two quinolone family members, ciprofloxacin and enoxacin

New rhenium complexes with ciprofloxacin as useful models for understanding the properties of [99mTc]-ciprofloxacin radiopharmaceutical

“…19,29,54 The presence of an oxorhenium metal fragment in 1 is also consistent with this IR spectrum, since an intense band at 896 cm -1 is observed, which can be assigned to the (Re=O) vibration. 55 The Therefore, we can suppose that the acid generated by the reaction with the carboxylic hydrogen atom is responsible for the protonation of the piperazine nitrogens.…”

“…22 The IR spectra also agrees with the proposed coordination for ciprofloxacin, showing two intense signals at 1614 and 1480 cm -1 , in concordance with the observed values for complexes 1-2, and with reported data for other complexes with this coordination. 19,29,54 No signal was observed at 1730 cm -1 , showing that this complex is free of contamination with ciprofloxacin and two intense peaks, assigned to the characteristic υ(CO) absorptions of the fac-{Re(CO) 3 } fragment,…”

“…Thus, in most of these studies, the reported antimicrobial activities are very similar to, or slightly lower than, those of free quinolones. 19,23,54,58 A c c e p t e d m a n u s c r i p t…”

Third generation fluoroquinolones antibacterial drug based mixed-ligand Cu(II) complexes: structure, antibacterial activity, superoxide dismutase activity and DNA–interaction approach

“…Quinolone-metal complexes have been studied mainly for their antibacterial activity against diverse microorganisms [6][7][8][9][10][11] and in some cases, for their interaction with DNA [12,13], exemplifying the important role of metal ions for the mechanism of action of these drugs. Specifically, the in-vitro cytotoxicity of the complex [(chloro)(2,2′-bipyridine)(N-propyl-norfloxacinato)copper(II)] against two leukaemia cell lines, HL-60 (human acute myeloid leukaemia) and K562 (human chronic myeloid leukaemia in blast crisis), revealed an increased antiproliferative and necrotic effect, in comparison to the free ligand Hprnorf [14].…”

Synthesis and crystal structure of a new polymer built from a cyano nickel(II) oxa-azamacrocyclic complex

“…For complex I, strong evidence that aldehyde groups had been completely converted into Schiff base residues was provided by the disappearance of the aldehydic C@O stretching band at 1680 cm À1 and the appearance of a strong band at 1635 ± 5 cm À1 assigned to m(C@N) stretching band [14]. Wide bands resulting from O-H stretching vibration of the coordinated and hydration water molecules emerge at 3196 and 3313 cm À1 , respectively [15,16] These major peaks are associated with peaks of mass one or two greater or less, which are attributed to protonated/deprotonated forms. This also accounts for the slight ambiguities in making assignments.…”