Abstract Interaction of the antimalarial chloroquine (CQ) with ferriprotoporphyrin IX, Fe (III) PPIX, was investigated in aqueous solution (pH 7.4) and as a precipitate from aqueous medium at pH 5.0. In solution, spectrophotometric titrations indicated strong association (logK obs 13.3±0.2) and a Job plot gave a stoichiometry of 1: 2 CQ: Fe (III) PPIX. UV–visible absorbance and magnetic circular dichroism spectra of the complex were compared to ...
[Margolis, Brandon J.; Long, Kimberly A.; Laird, Dana L. T.; Ruble, J. Craig; Pulley, Shon R. Journal of Organic Chemistry, 2007 , vol. 72, # 6 p. 2232 - 2235]