Pseudonaltrexone; 2,2′-Bisnaltrexone,(4R,4'R,5S,5'S,9R,9'R,17S,17'S)-3,3'-bis(cyclopropylmethyl)-5,5',12,12'-tetrahydroxy-2,2',3,3',4,4',5,5',6,6',7,7',9,9',18,18'-hexadecahydro-[13,13'-bi(4,12-methanobenzofuro[3,2-e]isoquinoline)]-8,8'(1H,1'H)-dione,Degradation product of Naltrexone,Naltrexone Therapeutic