3,4-MDPPP Hcl CAS # 24698-57-5 or 3,4-Methylenedioxy-α-Pyrrolidinopropiophenone (hydrochloride) joins structural features of the stimulants α-PPP and MDPV. Pyrrolidinophenones (PPPs) are related to compounds that shows a pyrrolidinyl group affixed to the narcotic cathinone.