SYNTHESES AND SINGLET OXYGEN REACTIVITY OF OXODIPYRROMETHENE MODELS FOR BILIRUBIN

Various oxodipyrromethenes with varying β-substituents have been synthesized and their reaction with singlet oxygen studied. The rates of chemical reactivity (kR) and physical quenching (kQ) of singlet oxygen by those substrates approach the diffusion threshold in both chloroform and methanol solvents, with kQ generally larger than kR in chloroform but of comparable magnitude in methanol. The range of (kQ+kR) values is 0.2-4.2 × 109 M-1 s-1. © 1979.