Exploring 1629. To explore a different substance…

Methyl 1-[2-(2-oxo-1,3-benzoxazol-3(2H)-yl)ethyl]-4-[phenyl(propanoyl)amino]piperidine-4-carboxylate
 1629  C25H29N3O5  451.515
 Fentanyl
 InChI=1S/C25H29N3O5/c1-3-22(29)28(19-9-5-4-6-10-19)25(23(30)32-2)13-15-26(16-14-25)17-18-27-20-11-7-8-12-21(20)33-24(27)31/h4-12H,3,13-18H2,1-2H3
 SNRCFUVGNPSHNJ-UHFFFAOYSA-N This stereoisomer Any stereoisomer
 CCC(=O)N(C1(CCN(CC1)CCn1c(=O)oc2c1cccc2)C(=O)OC)c1ccccc1