3,4-DehydroCilostazol (OPC-13015) is an active metabolite of Cilostazol. 3,4-DehydroCilostazol is used for pharmacokinetic study[1]. [1]. T R S Satheeshmanikandan, et al. Liquid Chromatography - Tandem Mass Spectrometry for the Simultaneous Quantitation of Glipizide, Cilostazol and Its Active Metabolite 3, 4-dehydro-cilostazol in Rat Plasma: Application for a Pharmacokinetic Study. Arzneimittelforschung. 2012 Sep;62(9):425-32.