Formation of a Nonaoxirane from A2E, a Lipofuscin Fluorophore related to Macular Degeneration, and Evidence of Singlet Oxygen Involvement This work was supported by NIH grant GM 34509 (K.N.), NSF grant NSF-CHE-98-12676 (N.J.T. and S.J.), and NIH grant EY-12951 (J.R.S.).