4,6(1H,5H)-Pyrimidinedione, dihydro-5-((4-hydroxy-3-methoxyphenyl)methylene)-2-thioxo- (9CI) 4-25-00-00517 (Beilstein Handbook Reference) 5-Vanillylidene-2-thiobarbituric acid 73681-14-8 BARBITURIC ACID, 2-THIO-5-VANILLYLIDENE- BRN 0254168 NSC 509230