Ethyl 1,2,3,4-tetrahydro-4-oxo-2-thioxo-5-pyrimidinecarboxylate38026-46-931 % similar Thioguanine154-42-731 % similar 5-Bromo-4,6-dihydroxypyrimidine15726-38-230 % similar 6-Hydrazinyl-9H-purine5404-86-430 % similar 4,6-Dihydroxy-5-methylpyrimidine63447-38-130 % similar