The assignments structures of the four 1:1 pipemidic acid (pipH)–magnesium(II), calcium(II), zinc(II), and iron(III) complexes, [Mg(pip)(H2O)3(Cl)].6H2O, [Ca(pip)(H2O)3(Cl)].2H2O, [Zn(pip)(H2O)3(Cl)].4H2O, [Fe(pip)(H2O)2(Cl)2].6H2O, (where pip = deprotonated pipemidic), were synthesized through chemical reactions MgCl2.6H2O, CaCl2.2H2O, ZnCl2, FeCl3.6H2O metal salt chlorides with pipH chemother...