1-(1-Methyl-2-phenylethyl)-4-(N-propanilido)piperidine 79704-88-4 ALPHA-METHYLFENTANYL China White DEA No. 9814 N-(1-(1-Methyl-2-phenylethyl)-4-piperidinyl)-N-phenylpropanamide N-(1-(alpha-Methyl-beta-phenyl)ethyl-4-piperidyl)propionanilide Propanamide, N-(1-(1-methyl-2-phenylethyl)-4-piperidinyl)-N-phenyl- alpha Methyl fentanyl