Caging of Bodipy Photosensitizers through Hydrazone Bond Formation and their Activation Dynamics

Three unique hydrazone-based small-molecule-activatable photosensitizers were designed and synthesized. Two of them work efficiently in a low-pH environment, resembling the microenvironment of the cancerous tissues. The activation pathway is unique and based on hydrazone bond cleavage. They were investigated through in vitro cellular studies in aggressive cancer lines, and tumor-specific culture conditions successfully initiated the cleavage and activation of the cytotoxic singlet oxygen generation in the relevant time period. The interesting photophysical characteristics of the alpha- and beta-substituted hydrazone derivatives of the Bodipy structures and their mild hydrolysis methodologies were also investigated successfully.

Automated summary

Three unique hydrazone-based small-molecule-activatable photosensitizers were designed and synthesized. Two of them showed efficient performance in a low-pH environment, mimicking the microenvironment of cancerous tissues. The activation pathway is distinctive and relies on hydrazone bond cleavage. In vitro cellular studies using aggressive cancer lines and tumor-specific culture conditions successfully triggered the cleavage and activation of cytotoxic singlet oxygen production within the appropriate time frame. Additionally, the intriguing photophysical characteristics of alpha- and beta-substituted hydrazone derivatives of the Bodipy structures and their mild hydrolysis methods were also successfully investigated.