1,3,5-triazinane-2,4,6-trione 1,3,5-triazine-2,4,6(1H,3H,5H)-trione InChI=1/C3H3N3O3/c7-1-4-2(8)6-3(9)5-1/h(H3,4,5,6,7,8,9