10-(2-Hydroxylphenyl)-5,15-bis(pentafluorophenyl) corrole([STHZ]1) was found to have a remarkable photocytotoxicity on nasopharyngeal carcinoma(NPC) cell line(Chang C.K.et al.,Proc SPIE,2006,Vol.6139,p268).To explore the heavy-atom effect on corrole photosensitizer,an exact analogue of corole [STHZ]1[STBZ] with the modification of two heavy iodine atoms on its 10-phenyl group,10-(2-hydroxyl-3,5-diiodophenyl)-5,15-bis(pentafluorophenyl)corrole(2),were synthesized.Surprisingly,the photocytoxicity of corrole 2 on NPC cell dropped sharply as compared to corole 1.It exhibited no significant PDT cytotoxicity even if its concentration reached 2 μmol/L.This may be caused by the lowering of its singlet oxygen quantum yield in PDT, although the intersystem crossing of corrole 2 could be enhanced by iodine heavy-atom effect as indicated by the strong decrease of its fluorescence emission.
