Then, the substrate anion is oxidized by the O2 formed in the dismutation process. Conversely, the other two mechanisms involve direct oxidation by O2 •-or HO2 • . Considering the possible mechanisms and structure-decomposability relationship of T-705, its T-1105 moiety is thought to play a significant role in the oxidative decomposition mechanism. Our previous studies reported that O2 •-is eliminated by polyphenols, 1,4-and 1,2-benzendiols (hydroquinone 29 and catechol ), and mono-phenols including aminophenols through the oxidative electron transfer (ET) involved in the PCET. In these studies, the PCET mechanism is based on quinonehydroquinone π-conjugation and involves two PTs and one ET.