Syntheses of core-modified porphyrins, and their application to photodynamic therapy as sensitizers and halogenation reaction as catalysts

The research described in this thesis consists of five chapters. Chapter 1 describes syntheses of novel 21,23-dithia-porphyrins including their water soluble forms prepared for Photodynamic therapy (PDT) as sensitizers. This chapter also describes syntheses of novel meso-tetraarylsubstituted-21-telluraporphyrins used for halogenation reaction as catalysts.; Chapter 2 describes the application of water-soluble 21,23-dithia-porphyrins to PDT as sensitizers. Particularly, their photophysical and biological properties as sensitizers for PDT were evaluated. 5,10-bis-aryl-15,20-bis-(4-phenoxyacetc acid)-21,23-dithia-porphyrins are found to be promising sensitizers for PDT.; Chapter 3 focuses on physical properties of heteroatom-containing core-modified porphyrins. Especially, the impact of 21,23-heteroatom interactions on electrochemical redox potentials, 125Te NMR spectra, and absorption spectra was examined, which revealed that the 21-tellura analogues of 21- and 21,23-core-modified porphyrins have distinct properties compared with their lighter chalcogen analogues.; Chapter 4 describes an application of tellurium-containing, core-modified porphyrins as catalysts for hologenation reaction. Tellurium-containing, core-modified porphyrins showed the excellent catalytic performance for bromination reactions using hydrogen peroxide and sodium bromide.; Chapter 5 describes the synthesis, structure and spectral properties of a 21,21-dichloro-2l-telluraporphyrin. The 21,21-dichloro-2l-telluraporphyrin was prepared from a corresponding 21-oxo-telluraporphyrin simply by treatment with 1N HCl aqueous solution. This unique property of 21-oxo-telluraporphyrins enable them to work as catalysts for bromination reactions using hydrogen peroxide and sodium bromide described in chapter 4, and a 21,21-dichloro-21-telluraporphyrin would be considered as a key intermediate for the catalytic performance. A water-soluble 21,21-dichloro-telluraporphyrin was also prepared and showed great catalytic performance for bromination reaction in a homogenous system.