SPRINGFIELD, Virginia - July 2015: The United States Drug Enforcement Administration (DEA) issued a temporary ban for the synthetic opioid, N-(1-phenethylpiperidin-4-yl)-N-phenylacetamide (acetyl fentanyl), and its optical, positional, and geometric isomers, salts and salts of isomers. By order, effective since July 17 2015, acetyl fentanyl is a controlled substance under Schedule I of the Controlled Substances Act. In March 2015 the DEA issued a nationwide alert on fentanyl and its analogues based on the recent surge in death cases in multiple regions of the country. In addition to the United States of America acetyl fentanyl has been reported to the UNODC EWA since 2013 by Canada and the United Kingdom.

 
Chemical structure of acetyl fentanyl (Source: UNODC)

 For further information please see:
https://federalregister.gov/a/2015-17563
http://www.gpo.gov/fdsys/pkg/FR-2015-07-17/pdf/2015-17563.pdf