The Contribution of Singlet Oxygen to Insulin Resistance

Figure 5

Suggested RNH₂ and Fe²⁺ or cytochrome c-mediated conversion of cholesterol 5-hydroperoxide (29) to secosterol aldehyde A (30) via dioxetane (32), hydroperoxyvinyl ether (33) and the corresponding vinyl hemiacetal, or secondary ozonide (34). Although Hock cleavage of (29) also yields (30), the acidic conditions for Hock cleavage facilitate very rapid aldolization of (30) to form secosterol B (31).