Exploring 14391. To explore a different substance…

{1-[2-(1,3-Dioxo-1,3-dihydro-2H-isoindol-2-yl)ethyl]-4-[phenyl(propanoyl)amino]piperidin-4-yl}methyl ethyl carbonate
 14391  C28H33N3O6  507.578
 Fentanyl
 InChI=1S/C28H33N3O6/c1-3-24(32)31(21-10-6-5-7-11-21)28(20-37-27(35)36-4-2)14-16-29(17-15-28)18-19-30-25(33)22-12-8-9-13-23(22)26(30)34/h5-13H,3-4,14-20H2,1-2H3
 FFFVWIJXNCQDLE-UHFFFAOYSA-N This stereoisomer Any stereoisomer
 CCOC(=O)OCC1(CCN(CC1)CCN1C(=O)c2c(C1=O)cccc2)N(c1ccccc1)C(=O)CC