4'-methyl-α-pyrrolidinopropiophenone 4'-methyl-α-pyrrolidinopropiophenone 4'-methyl-α-pyrrolidinopropiophenone (4-meppp, mppp or mαppp) is a stimulant drug and substituted cathinone. it is structurally very similar to α-ppp, with only one added methyl group in the para position on the phenyl ring. 4-meppp was sold in germany as a designer drug in the late 1990s and early 2000s, along with a number of other pyrrolidinophenone derivatives. although it has never achieved the same international popularity as its better-known relations α-ppp and mdpv, 4-meppp is still sometimes found as an ingredient of grey-market "bath salt" blends such as "nrg-3". not to be confused with desmethylprodine (opioid drug with acronym mppp), mptp (neurotoxic impurity of desmethylprodine synthesis) or mpp+ (neurotoxic metabolite of mptp). 4'-methyl-α-pyrrolidinopropiophenonelegal statuslegal status de: anlage i (authorized scientific use only) uk: class b us: schedule i banned in sweden identifiers iupac name (rs)-1-(4-methylphenyl)-2-(1-pyrrolidinyl)-1-propanone cas number28117-80-8 1313393-58-6 (hydrochloride)pubchem cid6430745chemspider4936084unii0ty023967icomptox dashboard (epa)dtxsid80891438 chemical and physical dataformulac14h19nomolar mass217.312 g·mol−13d model (jsmol)interactive image smiles cc1=cc=c(c=c1)c(=o)c(c)n2cccc2 inchi inchi=1s/c14h19no/c1-11-5-7-13(8-6-11)14(16)12(2)15-9-3-4-10-15/h5-8,12h,3-4,9-10h2,1-2h3key:apsjunfbaxixlk-uhfffaoysa-n legality in the united states 4-meppp is considered a schedule 1 controlled substance as an positional isomer of alpha-pyrrolidinopentiophenone (α-pvp)