The molecule is the conjugate acid of morphine arising from protonation of the tertiary amino group; major species at pH 7.3. It is an ammonium ion derivative and an organic cation. It is a conjugate acid of a morphine.
(4R,4aR,7S,7aR,12bS)-3-methyl-1,2,3,4,4a,7,7a,13-octahydro-4,12-methanobenzofuro[3,2-e]isoquinolin-3-ium-7,9-diol