Pursuing the Red-Shift in Glycoporphyrins─A New Synthetic Approach toward Glycoconjugates from the meso-Tetraethynylporphyrin Scaffold

Abstract

Photodynamic therapy is a promising approach to anticancer treatment. For further development of this technique, new photosensitizers that better meet biological criteria are highly desired. Glycoporphyrins are considered more than favorable synthetic targets in this matter. This is due to their increased solubility in aqueous solutions and their targeting ability toward cancer cells. Herein, we report synthetic studies, and we propose an original Sonogashira-based strategy toward unique porphyrin-glycal conjugates. The proposed methodology allowed us to synthesize 5 new examples of photosensitizers in which the sugar unit influenced another crucial factor─the bathochromic shift of the photosensitizer’s absorption profile. These structures were able to absorb wavelengths from the region of 740–780 nm. The studies present the development of a synthetic strategy toward water-soluble glycoporphyrins and the initial recognition of their singlet oxygen production ability.