Nalorphine (INN; Lethidrone, Nalline), also known as N-allyl-normorphine, is a mixed opioid agonist–antagonist. It acts at two opioid receptors, at the mu receptor it has antagonistic effects and at the kappa receptors it exerts high-efficacy agonistic characteristics. It is used to reverse opioid overdose and (starting in the 1950s) in a challenge test to determine opioid dependence.^[1]

More recently, it has become much more commonplace to use ethyl chloroformate instead of cyanogen bromide for the Von Braun degradation demethylation step. See for example the list of phenyltropanes or the synthesis of paroxetine for further examples of this.