Synthesis and Evaluation of Novel meso-Tetraphenyltetrabenzoporphyrins for Photodynamic Therapy.

ABSTRACT

To discover effective photosensitizers for photodynamic therapy (PDT), a series of new meso-tetraphenyltetrabenzoporphyrin (m-Ph4TBP) derivatives were designed, prepared, and characterized. All m-Ph4TBPs own two characteristic absorption bands in the range of 450-500 and 600-700 nm and have the ability to generate singlet oxygen upon photoexcitation. Most of the m-Ph4TBPs demonstrated high photoactivity, among which compounds I4, I6, I12, and I13 induced apoptosis and also exhibited excellent photodynamic activities in vivo. Nonetheless, the liver organs of the I4 and I6-PDT groups showed clear calcifications, whereas the liver tissues of the other PDT groups showed no calcification. It was indicated that compared to phenolic m-Ph4TBPs, glycol m-Ph4TBPs exhibited superior biological safety in mice. According to comprehensive evaluations, m-Ph4TBP I12 displayed excellent photodynamic antitumor efficacy and biological safety and can be regarded as a promising antitumor drug candidate.