IMINIUM SALT BENZOCHLORINS - STRUCTURE-ACTIVITY RELATIONSHIP STUDIES

An iminium salt of copper(II) octaethylbenzochlorin (CDS1) is an effec tive new photosensitizer despite the fact that it does not produce sin glet oxygen, does not fluoresce and the triplet state lifetime can onl y be less than 20 ns. A number of octaethylbenzochlorin derivatives we re synthesized in order to determine the structural component(s) that is(are) responsible for the photodynamic action of these new photosens itizers. Studies utilizing the (4-[5-nitro-2-furyl]-2-thiazolyl)formam ide-induced urothelial tumor revealed that the coexistence of the copp er inside the aromatic ring and the iminium group at the meso position are required for the photodynamic effect.