5-{N-[4-(4'-chlorophenoxy)but-2-ynyl]-N-ethylamino}-1,3-dimethyluracil
1,3-dimethyl-5-{N-[4-(4'-methylphenoxy)but-2-ynyl]-N-ethylamino}uracil
5-{N-[4-(2'-chlorophenoxy)but-2-ynyl]-N-ethylamino}-1,3-dimethyluracil
5-((2-bromo-5-methoxybenzyl)(ethyl)amino)-1,3-dimethylpyrimidine-4(1H,3H)-dione
5-((2-bromobenzyl)(ethyl)amino)-1,3-dimethylpyrimidine-2,4(1H,3H)-dione