Synthesis of esters and amides of 1,4-dihydro-1,2,4,5-tetrazine-3,6-dicarboxylic acid

Alkyl esters and alkyl amides of 1,4-dihydro-1,2,4,5-tetrazine-3,6-dicarboxylic acid were synthesised and characterised by IR, 1 H NMR, El-MS and elemental analysis. The structure of 1,4-dihydro-1,2,4,5-tetrazine-3,6-dicarboxylic was confirmed by X-ray diffraction analysis. Some selected compounds were evaluated against P-388 and A-549 cancer cell lines, but showed poor inhibitory activities.