2389-75-5 4,11-Dichloroquinacridonequinone 4,11-Dichloroquino(2,3-b)acridine-6,7,13,14(5H,12H)-tetrone EINECS 219-224-7 Quino(2,3-b)acridine-6,7,13,14(5H,12H)-tetrone, 4,11-dichloro-