dimethyl 4-chloro-2,6-pyridinedicarboxylate
4-amino-2,6-pyridinedicarboxylic acid
dimethyl 4-hydroxypyridine-2,6-dicarboxylate
4-oxo-1,4-dihydro-pyridine-2,6-dicarboxylic acid dimethyl ester
bis-pentafluorophenyl 4-pentyloxycarbonylmethoxypyridine-2,6-dicarboxylate