3f-neb 3f-neb 3-fluoro-n-ethylbuphedrone (3f-neb) is a substituted cathinone derivative with stimulant effects which has been sold as a designer drug. it was first identified in sweden in 2021. 3f-neblegal statuslegal status de: anlage ii (authorized trade only, not prescriptible) uk: class b identifiers iupac name 2-(ethylamino)-1-(3-fluorophenyl)butan-1-one pubchem cid164946359chemical and physical dataformulac12h16fnomolar mass209.264 g·mol−13d model (jsmol)interactive image smiles ccc(c(=o)c1=cc(=cc=c1)f)ncc inchi inchi=1s/c12h16fno/c1-3-11(14-4-2)12(15)9-6-5-7-10(13)8-9/h5-8,11,14h,3-4h2,1-2h3key:flfafggbruxybd-uhfffaoysa-n