Notes: (±)-2-propyl-4-Pentenoic acid (4-ene VPA) is a major metabolite of valproic acid (Item No. 13033).{39466} It undergoes β-oxidation to form reactive metabolites that induce hepatotoxicity in rats. 4-ene VPA is also neuroteratogenic, reducing forebrain size and inducing deformation of the neural tube in mouse embryos.{39467}