Purpurinimides as photosensitizers: effect of the presence and position of the substituents in the in vivo photodynamic efficacy.

This study presents a novel approach for the regioselective synthesis of a series of alkyl ether analogues of purpurin-18-N-alkylimide. In the purpurinimide series, this is the first example which demonstrates that the presence and position of the substituents in the macrocycle makes a remarkable difference in the in vivo PDT efficacy.