NFEPP

NFEPP (N-(3-fluoro-1-phenethylpiperidin-4-yl)-N-phenylpropionamide) is an analgesic opioid chemical, similar in structure to fentanyl, designed in 2016 by Spahn et al. from Free University of Berlin^[2] to avoid the standard negative side effects of opiates, including opioid overdose, by only targeting inflamed tissue.^[3][4]

NFEPP

Clinical data
Drug class	Opioid
Legal status
Legal status	US: Schedule I[1]
Identifiers
IUPAC name N-(3-Fluoro-1-phenethylpiperidin-4-yl)-N-phenylpropionamide
CAS Number	1422952-84-8
ChemSpider	58826238
UNII	NXR38LA4PA
CompTox Dashboard (EPA)	DTXSID101040109
Chemical and physical data
Formula	C22H27FN2O
Molar mass	354.469 g·mol−1
3D model (JSmol)	Interactive image
SMILES CCC(=O)N(c1ccccc1)[C@H]2CCN(C[C@H]2F)CCc3ccccc3
InChI InChI=1S/C22H27FN2O/c1-2-22(26)25(19-11-7-4-8-12-19)21-14-16-24(17-20(21)23)15-13-18-9-5-3-6-10-18/h3-12,20-21H,2,13-17H2,1H3/t20-,21+/m1/s1 Key:DMCQJJAWMFBPOX-RTWAWAEBSA-N

Inflamed tissue

Inflamed tissue has a lower pH value (~5–7) than non-inflamed tissue (7.4).^[5] Through computer simulation, scientists found a way to make the fentanyl analog only affect inflamed tissue via the addition of fluorine to the chemical structure. In experiment, it was shown that NFEPP produced injury-restricted analgesia in rats with different types of inflammatory pain without exhibiting typical opiate effects, including respiratory depression, sedation, constipation, and chemical seeking behavior.^[6][7][8]

As a result, NFEPP has the potential to reduce opioid addiction and dependency, as there is no effect on users who are not actually suffering from pain, as the chemical does not interact with non-inflamed brain tissue until much higher doses are reached.^[9]