16490-15-6 2-Thioorotic acid (VAN) 2-Thiouracil-4-carboxylic acid 4-Pyrimidinecarboxylic acid, 1,2,3,6-tetrahydro-6-oxo-2-thioxo- 6-Carboxy-2-thiouracil 6953-78-2 AI3-26587 Mercaptoorotic acid NSC 39961 Orotic acid, 2-thio- (VAN) (8CI)