N,O-Didesmethyltramadol
N,''O-Didesmethyltramadol is an opioid derivative which is one of two active metabolites of the opioid analgesic medication tramadol. It is many times less potent than the other active metabolite O-Desmethyltramadol but is still more potent as a mu opioid receptor agonist than tramadol itself, unlike the other metabolites N''-desmethyltramadol, N,''N-didesmethyltramadol, and N'',N,''O-tridesmethyltramadol which are entirely without opioid activity. As with tramadol and O''-desmethyltramadol it is found as a mixture of the - and -enantiomers, although the separate enantiomers of N,''O-didesmethyltramadol have not been studied individually. It is specifically listed as a Schedule I drug in Canada, presumably due to concerns it may be subject to abuse as a designer drug in a similar manner to other opioid active metabolites such as O''-desmethyltramadol and nortilidine.