Gravar-mail: Ethyl 1′′-benzyl-2′′-oxo-2′,3′,5′,6′,7′,7a’-hexa­hydro-1′H-di­spiro­[indeno­[1,2-b]quinoxaline-11,2′-pyrrolizine-3′,3′′-indoline]-1′-carboxyl­ate monohydrate