Near - infrared absorbing phthalocyanines: second - generation of photosensitizers for photodynamic therapy in the therapeutic biologic window

Abstract

Photodynamic therapy (PDT) is an alternate cancer therapy and it emphasizes the key role of the light and the photosensitizer as well. A photosensitizer is a chemical compound and has special photophysical properties, which can be suitable for the photodynamic therapy process itself. As a kind of promising second-generation photosensitizer, phthalocyanines have been investigated for a long time in photodynamic therapy field. Many novel phthalocyanines are obtained by various structural modifications on them. Recently, attempts to optimize phthalocyanines for PDT focused on the development of near- infrared (NIR) absorbing phthalocyanines. The most important reason for this is the ability of phthalocyanines absorbing in NIR region allows phthalocyanines to penetrate deeper in the tissue and in the therapeutic window as well. For this reason, in this thesis thiol substituted phthalonitriles and their related derivatives nonperipheral octa -SR phthalocyanines have been designed and synthesized. These molecules were characterized with MALDI, ATR-IR, UV-Vis and NMR spectroscopy. Additionally, while aiming a new substitution pattern for phthalocyanines a novel asymmetric AB3 type -diSO2 substituted phthalocyanine was investigated.