26248-99-7 Daxan EINECS 247-543-1 Imidazo(4,5-d)imidazole-2,5(1H,3H)-dione, tetrachlorotetrahydro- Tetrachloroglycoluril Tetrachlorotetrahydroimidazo(4,5-d)imidazole-2,5(1H,3H)-dione