Exploring 1618. To explore a different substance…

Methyl 4-[phenyl(propanoyl)amino]-1-[2-(1H-pyrazol-1-yl)ethyl]piperidine-4-carboxylate
 1618  C21H28N4O3  384.472
 Fentanyl
 InChI=1S/C21H28N4O3/c1-3-19(26)25(18-8-5-4-6-9-18)21(20(27)28-2)10-14-23(15-11-21)16-17-24-13-7-12-22-24/h4-9,12-13H,3,10-11,14-17H2,1-2H3
 QLTFJNWRBMIGIS-UHFFFAOYSA-N This stereoisomer Any stereoisomer
 COC(=O)C1(CCN(CC1)CCn1cccn1)N(c1ccccc1)C(=O)CC