A simple synthetic route to a ruthenium(II)-2,3-naphthalocyanine-bis-benzonitrile complex is presented. A series of ligands can be substituted in the axial position of this complex, which confers water solubility on the ruthenium(II)-2,3-naphthalocyanines (Ru(II) -2,3-Ncs). The ability of these complexes to function as potential sensitizers for photodynamic therapy was investigated. The sensitizers presented in this paper have Q-band absorption maxima in the 710–760 nm range, with extinction coefficients around 1 × 10 5 M −1 cm −1 . The activity of these complexes was tested in vitro against the HeLa cell line and was found to be in the micromolar range. The photobleaching of the complexes was also studied.
