2,4,6(1H,3H,5H)-Pyrimidinetrione, 5-(1,3-dimethyl-2-butenyl)-5-ethyl- (9CI) 3625-18-1 5-(1,3-Dimethyl-2-butenyl)-5-ethylbarbituric acid BARBITURIC ACID, 5-(1,3-DIMETHYL-2-BUTENYL)-5-ETHYL- McN-481 Mcneil 481 NSC 42268