alkaline-earth picrates were carried out in a waterchloroform system using newly synthesized tetralactams containing dimethyleneoxy moieties. These ligands display excellent extracting properties for Ca2+, Ba2+, and Sr2+ cations. Some of the less lipophilic derivatives have greater preference for Ba2+ vs. Na+ and Zn2+ and, to a lesser extent, K+, Mg2+ and Ca2+. In addition, the stability constants were determined