5,5-DIBROMOMELDRUM'S ACID

Methylenedisalicylic acid

5,6,7,8-TETRAHYDRO-2-NAPHTHOIC ACID

5,6,7,8-Tetrahydroquinoxaline

5,6-DICHLORO-2,3-DICYANOPYRAZINE

5,6-DICHLORO-2,3-DICYANOPYRAZINE

2,4,4,6-TETRAMETHYL-1-OXA-3-AZA-2-CYCLOHEXENE

5,6-DIHYDRO-2-PHENYL-4,4,6-TRIMETHYL-1,3(4H)-OXAZINE

5,6-DIPHENYL-2,3-DIHYDROPYRAZINE