N-(2-Amino-pyridin-3-yl)-4-methyl-N-(4-methyl-phenyl-sulfon-yl)benzene-sulfonamide.

The title compound, C(19)H(19)N(3)O(4)S(2), was prepared by the reaction of 2,3-diamino-pyridine with tosyl chloride in a mixture of dichloro-methane-pyridine as solvent. In the crystal, mol-ecules associate via pairs of N-H⋯N hydrogen bonds, forming a centrosymmetric eight-membered {⋯HNCN}(2) synthon. The dihedral angles between the amino-pyridine ring and the tosyl benzene rings are 50.01†(6) and 32.01†(4)°.