5-Nitro-2,4(1H,3H)-pyrimidinedione611-08-530 % similar 5-Acetyl-2,4(1H,3H)-pyrimidinedione6214-65-930 % similar 7-Deazaxanthine39929-79-830 % similar 5-(Hydroxymethyl)uracil4433-40-330 % similar