Syntheses of new chlorin derivatives containing maleimide functional group and their photodynamic activity evaluation.

Nine new chlorin derivatives containing maleimide functional group and amino acid residue with chlorin e6 scaffold (compounds 1-6) or pheophorbide a scaffold (compounds 7-9) were synthesised from chlorophyll a. The all nine derivatives demonstrated increased photo cytotoxic activity in HepG2 cell (IC50 3.2-20.5 μM) comparing with chlorin e6 and its trimethyl ester. Their photo cytotoxicities were approximately dependent on their abilities to produce singlet oxygen ((1)O2) in the cells.