Email (record): 1,1′′-Bis(prop-2-en-1-yl)-1,1′′,2,2′′-tetra­hydro­dispiro­[indole-3,7′-[6,9]diaza­tricyclo­[7.3.0.0(2,6)]dodecane-8′,3′′-indole]-2,2′′-dione