Crotonylfentanyl
(2E)-N-Phenyl-N-[1-(2-phenylethyl)piperidin-4-yl]but-2-enamide
 1635  C23H28N2O  348.481
 Fentanyl
 InChI=1S/C23H28N2O/c1-2-9-23(26)25(21-12-7-4-8-13-21)22-15-18-24(19-16-22)17-14-20-10-5-3-6-11-20/h2-13,22H,14-19H2,1H3/b9-2+
 VDYXGPCGBKLRDA-XNWCZRBMSA-N This stereoisomer Any stereoisomer
 C/C=C/C(=O)N(c1ccccc1)C1CCN(CC1)CCc1ccccc1