4f-php 4f-php 4-fluoro-alpha-php (4f-php) is a recreational designer drug from the substituted cathinone family with stimulant effects, which first appeared on the illicit market in around 2017. 4-fluoro-alpha-phpidentifiers iupac name 1-(4-fluorophenyl)-2-(pyrrolidin-1-yl)hexan-1-one cas number2230706-09-7pubchem cid132989300chemical and physical dataformulac16h22fnomolar mass263.356 g·mol−13d model (jsmol)interactive image smiles ccccc(c(=o)c1=cc=c(c=c1)f)n2cccc2 inchi inchi=1s/c16h22fno/c1-2-3-6-15(18-11-4-5-12-18)16(19)13-7-9-14(17)10-8-13/h7-10,15h,2-6,11-12h2,1h3key:bcjxlsgkmnrrko-uhfffaoysa-n