1,2,4-Triazine-3,5(2H,4H)-dione 4(6)-Azauracil 461-89-2 6-Azauracil AZU Azauracil NSC 3425 NSC3425 Usaf cb-30 WLN: T6NMVMVJ as-Triazine-3,5(2H,4H)-dione as-Triazine-3,5-diol