The structures of two brucinium (2,3-dimethoxy-10-oxostrychnidinium) salts of the alpha-hydroxy acids L-malic acid and L-tartaric acid, namely brucinium hydrogen (S)-malate pentahydrate, C23H27N2O4+.C4H5O5-.5H2O, (I), and anhydrous brucinium hydrogen (2R,3R)-tartrate, C23H27N2O4+.C4H5O6-,(II), have