ammonium 1-ethyl 2,7-dihydro-3-methyl-6-[(4-methyl-2-sulphonatophenyl)amino]-2,7-dioxo-3H-dibenz[f,ij]isoquinoline-1-carboxylate

2-[[[1-(Ethoxycarbonyl)-3,7-dihydro-3-methyl-2,7-dioxo-2H-dibenz[f,ij]isoquinolin]-6-yl]amino]-5-methylbenzenesulfonic acid ammonium salt