4,5-DIHYDRO-4-OXOFURO[3,2-C]PYRIDINE

4,5-DIMETHYL-2-FURALDEHYDE

3,6-Dihydroxy-4,5-dimethylpyridazine

4,5-DIPHENYLIMIDAZOLIN-2-ONE

4',6-Diamidino-2-phenylindole dihydrochloride

4,6-DIAMINO-2-MERCAPTOPYRIMIDINE

4,6-DIAMINO-2-METHYLMERCAPTOPYRIMIDINE

4,6-DICHLORO-2,8-DIMETHYLQUINOLINE

3,5-DICHLORO-6-PHENYLPYRIDAZINE

4,6-Dihydroxy-2-methylpyrimidine