Pyridine series

3,3'-Dihydroxybenzidine

4-Phenylethynylphthalic anhydride

1,4,5,8-Naphthalenetetracarboxylic dianhydride (NTDA)

3,3,4,4-diphenylsulfonetetracarboxy licdianhydride (DSDA)

1,4-Phenylene Bis(1,3-dioxo-1,3-dihydroisobenzof uran-5-carboxylate) (TAHQ)

4,6-di(1-adamantanyl)-1,3-bis(4- anmino-3-hydroxyphenoxy) benzene

bis[(3,4-dicarboxylic anhydride) phenyl]terephthalate (PHAP)

1,3-dioxo-1,3-dihydroisobenzofuran -5-yl 1,3-dioxo-1,3-dihydroisobenzofuran -5-carboxylate (8CI)

[4-(4-aminobenzoyl)oxyphenyl] 4-aminobenzoate (ABHQ)