Syntheses and photodynamic properties of glucopyranoside-conjugated indium(III) porphyrins as a bifunctional agent

The glucopyranoside-conjugated porphyrins, H2TPP{p-O-(CH2)2-O-OAcGlc} (1), [InTPP{p-O-(CH2)2-O-OAcGlc}]NO3 (2), H2TPP{p-O-(CH2)2-O-Glc} (3), [InTPP{p-O-(CH2)2-O-Glc]-NO3 (4) and ZnTPP{p-O-(CH2)2-O-OAcGlc} (5) were synthesized, and characterized by 1H NMR, 13C NMR, ESI-MS, UV-vis spectroscopies and elemental analyses. In the 1H NMR spectrum of 2, two sets of signals were observed for H-atoms of the phenyl group of porphyrin, indicating that 2 has the axial chirality due to a NO3 ion coordinating to the indium atom. Abilities of the singlet oxygen production of these porphyrins, investigated by using 1,3-diphenylisobenzofuran (DPBF) as a quencher, were higher than those of the free-based and zinc porphyrins, reflecting the heavy atom effect. The photodynamic properties of these porphyrin derivatives were investigated against COLO 679. All of the glucopyranoside-conjugated porphyrins exhibited the high photocytotoxicity compared with Laserphyrin®. Above all, 4 exhibited the highest photocytotoxicity, coinciding with the high abilities of this complex for the singlet oxygen production and the cell permeability.