Crystal structures and hydrogen bonding in the co-crystalline adducts of 3,5-di­nitro­benzoic acid with 4-amino­salicylic acid and 2-hy­droxy-3-(1H-indol-3-yl)propenoic acid

The structures of the co-crystalline adducts of 3,5-di­nitro­benzoic acid (3,5-DNBA) with 4-amino­salicylic acid (PASA), the 1:1 partial hydrate, C(7)H(4)N(2)O(6)·C(7)H(7)NO(3)·0.2H(2)O, (I), and with 2-hy­droxy-3-(1H-indol-3-yl)propenoic acid (HIPA), the 1:1:1 d (6)-dimethyl sulfoxide solvate, C(7)H(4)N(2)O(6)·C(11)H(9)NO(3)·C(2)D(6)OS, (II), are reported. The crystal substructure of (I) comprises two centrosymmetric hydrogen-bonded R (2) (2)(8) homodimers, one with 3,5-DNBA, the other with PASA, and an R (2) (2)(8) 3,5-DNBA–PASA heterodimer. In the crystal, inter-unit amine N—H⋯O and water O—H⋯O hydrogen bonds generate a three-dimensional supra­molecular structure. In (II), the asymmetric unit consists of the three constituent mol­ecules, which form an essentially planar cyclic hydrogen-bonded heterotrimer unit [graph set R (3) (2)(17)] through carboxyl, hy­droxy and amino groups. These units associate across a crystallographic inversion centre through the HIPA carb­oxy­lic acid group in an R (2) (2)(8) hydrogen-bonding association, giving a zero-dimensional structure lying parallel to (100). In both structures, π–π inter­actions are present [minimum ring-centroid separations = 3.6471 (18) Å in (I) and 3.5819 (10) Å in (II)].