rel-(3R,11bR)-1,3,4,6,7,11b-Hexahydro-3-(2-hydroxy-2-methylpropyl)-9,10-di(methoxy-d3)-2H-benzo[a]quinolizin-2-one,rel-(3R,11bR)-1,3,4,6,7,11b-Hexahydro-3-(2-hydroxy-2-methylpropyl)-9,10-di(methoxy-d3)-2H-benzo[a]quinolizin-2-one,Tetrabenazine Metabolite