Some tridentate ligands have been prepared for coordination of zinc (I1) ions (or cobalt (II), which acts as a surrogate for Zn (I1) ions) in a manner analogous to the coordination found in liver alcohol dehydrogenase. This entails coordination of the metal ion to two thiolates and an imidazole. The ligands must be sufficiently sterically hindered to prevent thiolate from acting as a bridging ligand between two metal ions. For some aspects of this work pyridine ...