2-Amino-3-carb­oxy­pyridinium perchlorate

The asymmetric unit includes two crystallographically independent equivalents of the title salt, C₆H₇N₂O₂⁺·ClO₄⁻. The cations and anions form separate layers alternating along the c axis, which are linked by N—H...O, O—H...O and C—H...O hydrogen bonds into a two-dimensional network parallel to (100). Further C—H...O contacts connect these layers, forming a three-dimensional network, in which R₄⁴(20) rings and C₂²(11) infinite chains can be identified.