Three-dimensional hydrogen-bonded structures in the hydrated proton-transfer salts of isonipecotamide with the di­carb­oxy­lic oxalic and adipic acid homologues

The structures of the 1:1 hydrated proton-transfer compounds of isonipecotamide (piperidine-4-carboxamide) with oxalic acid and adipic acid are three-dimensional hydrogen-bonded constructs involving several different types of enlarged water-bridged cyclic associations.