CP94 (Synonyms: CGP 46700, 1,2-Diethyl-3-hydroxypyridin-4-one, EL1Net, 1,2-diethyl HP)

CP94 is an iron chelator.¹ It enhances protoporphyrin IX photobleaching and decreases in the viability of A431 squamous epithelial carcinoma cells when used at a concentration of 150 µM in combination with photodynamic therapy (PDT) mediated by the protoporphyrin IX precursors aminolevulinic acid (ALA), methyl aminolevulinate (MAL), or hexylaminolevulinate .² CP94 (2 mg/ml in the drinking water) decreases hepatic total non-heme and ferritin-stored iron levels, as well as increases hepatic protoporphyrin levels, in mice.³ It also reduces ferrocene-induced increases in rat brain iron levels when administered at a dose of 100 mg/kg.⁴

1.Dobbin, P.S., Hider, R.C., Hall, A.D., et al.Synthesis, physicochemical properties, and biological evaluation of N-substituted 2-alkyl-3-hydroxy-4(1H)-pyridinones: Orally active iron chelators with clinical potentialJ. Med. Chem.36(17)2448-2458(1993) 2.Blake, E., Allen, J., and Curnow, A.The effects of protoporphyrin IX-induced photodynamic therapy with and without iron chelation on human squamous carcinoma cells cultured under normoxic, hypoxic and hyperoxic conditionsPhotodiagnosis Photodyn. Ther.10(4)575-582(2013) 3.Smith, A.G., Clothier, B., Francis, J.E., et al.Protoporphyria induced by the orally active iron chelator 1,2-diethyl-3-hydroxypyridin-4-one in C57BL/10ScSn miceBlood89(3)1045-1051(1997) 4.Ward, R.J., Dexter, D., Florence, A., et al.Brain iron in the ferrocene-loaded rat: its chelation and influence on dopamine metabolismBiochem. Pharmacol.49(12)1821-1826(1995)