Development Of Phenoxazinium Chalcogen Analogues As Photosensitizers’ Design, Synthesis And Property Study

Abstract:Photodynamic therapy (PDT), an experimental modality for treating solid tumors, is currently undergoing clinical evaluation. Compared with traditional therapeutic methods such as surgery, radiotherapy and chemotherapy, PDT is noninvasive and has low toxicity, good selectivity and can be used for repeatable treatment.Photosensitizer (PS) is the key component during PDT treatment. Hematoporphyrin derivative (HPD), the most widely studied PDT drugs, plays an important role in the development of PDT. However, due to its complex components, poor selectivity and stability, weak absorption in red region, HPD is far away from the ideal PDT agents. Therefore, there is a high demand in developing improved PSs.Phenoxazinium chalcogen analogues have strong absorption in red region, no dark cytotoxicity, good selectivity to tumors and cancer cells as well as remarkable photoactivity. In order to study the relationship of structure and phototherapeutic effects, we developed a series of new phenoxazinium chalcogen PSs having different of functional groups including methyl group, ethyl group, hydroxyl group, carboxyl group, sulfonic acid group and ester group. Importantly, we developed a new synthetic method by using nano-CuO to synthetize benzophenoselenazine derivatives’precursor under mild conditions with a high yield. Moreover, we designed and synthesized a kind of novel phenoxazinium chalcogen PSs by using tetrahydroquinoxaline framework as electron donors, which exhibit strong absorption above700nm.All the new PSs are characterized by1H NMR and their photophysical properties such as UV-Vis, fluorescence are investigated.