A simple and efficient route for preparing 2,3,5,6-tetraaminopyridine hydrochloride salt.

A simple and efficient route for preparing 2,3,5,6-tetraaminopyridine hydrochloride salt (TAP x 3HCl x H(2)O) was introduced in this paper. The title compound was synthesized, as usual, in two steps (nitration and hydrogenation) with a total yield of 90%. The use of an oleum and fuming nitric acid mixture in the nitration step improved the yield and purity of the intermediate product. A highly efficient hydrogenation using a H(2)/Pd/C/C(2)H(5)OH system was developed. The products were characterized by TG, IR, (1)H-NMR, (13)C-NMR, HPLC and elemental analysis.