Naltrexone EP Impurity B HCl;Naltrexone methylbromide Impurity G;Naltrexone Impurity 6(Naltrexone EP Impurity B);Naltrexone Hydrochloride EP Impurity B as Hydrochloride;(5alpha)-4,5-epoxy-3,14-dihydroxymorphinan-6-one hydrochloride;Naloxone Hydrochloride Dihydrate EP Impurity A as Hydrochloride;Noroxymorphone Hydrochloride CII (50 mg) (4,5alpha-Epoxy-3,14-dihydroxymorphinan-6-one hydrochloride);(4R,4aS,7aR,12bS)-4a,9-dihydroxy-2,3,4,4a,5,6-hexahydro-1H-4,12-methanobenzofuro[3,2-e]isoquinolin-7(7aH)-one hydrochloride