Dehydroxytramadol Hydrochloride;Tramadol Impurity 2(Tramadol EP Impurity B);1,2-Dehydroxy Tramadol Hydrochloride (~85%);Tramadol EP Impurity B HCl;Tramadol Impurity B;Tramadol imp B;[2-(3-Methoxyphenyl)cyclohex-1-enyl]-N,N-dimethylmethanamine Hydrochloride;Tramadol Hydrochloride Impurity B as Hydrochloride