2-Amino-5-methyl-4,6(1H,5H)-pyrimidinedione55477-35-5100 % similar Bromisoval496-67-339 % similar 5-Isopropylhydantoin16935-34-531 % similar Isobutyrohydrazide3619-17-831 % similar Dihydrothymine696-04-830 % similar