6-Bromo-1,2,4-triazine-3,5(2H,4H)-dione4956-05-232 % similar 4-Thiouracil591-28-632 % similar 6-Azathymine932-53-632 % similar Xanthine69-89-631 % similar 5-Bromo-2(1H)-pyrimidinone214290-49-030 % similar 5-Bromo-2(1H)-pyrimidinone38353-06-930 % similar 2-Pyrimidinone hydrochloride38353-09-230 % similar 5-Chloro-2(1H)-pyrimidinone54326-16-830 % similar 4,5-Dihydro-1H-1,2,4-triazol-5-one930-33-630 % similar