Modifications for Peripheral Structures of Purpurin-18 and Synthesis of Chlorophyllous Chlorin Derivatives

Abstract

Purpurin-18 methyl ester was used as a starting material, and the modifications for the structure on the terminal of its N-N-axis were completed making use of electron-richous properties of C(3)-vinyl group by various reactions including oxidation, reduction, electrophilic addition and 1,3-polar cycloaddition. The substituted groups, which could conjugated with macrocyclic chromophore in different form, were introduce to 3-position on the periphery, respectively. The synthesis of 11 unreported chlorophyllous chlorins with basic skeloton of purpurin-18 was accomplished and their chemical structures were characterized by elemental analysis, UV, IR and H NMR spectra. The influence of peripheric structure of purpurin-18 on their electronic spectrum was discussed and the possible mechanisms about corresponding reactions were tentatively proposed.