10-((4-Hydroxypiperidin-1-yl)methyl)chromeno[4,3,2-de]phthalazin-3(2H)-one (E7016), an inhibitor of poly(ADP-ribose) polymerase, is being developed for anticancer therapy. One of the major metabolites identified in preclinical animal studies was the product of an apparent oxidation and ring opening of the 4-hydroxypiperidine. In vitro, this oxidized metabolite could not be generated by incubati...
