Significant Tumor Inhibition of Trimethyl‐152‐[L‐aspartyl]pheophorbide a in Tumor Photodynamic Therapy≠

-[L-aspartyl]pheophorbide a was synthesised and investigated for anti-tumor activity. The prepared photosensitizer had good absorption in the phototherapeutic window and high ROS yields. It exhibited excellent phototoxicity higher than reference compound m-THPC when irradiated by 650 nm light in vitro, and obvious photodynamic anti-tumor effect in vivo. It causes cellular apoptosis or necrosis under laser irradiation and localizes in mitochondria, lysosome, and endoplasmic reticulum. The observed high efficacy was rationalized by efficient introduction into the blood by facile transfer through membranes, which is supported by molecular dynamics simulation studies. This work provides a new candidate photosensitizer for anti-cancer treatment.