Two tetradentate chelate systems have been synthesized in order to prepare metal complexes with oxorhenium (V) whose structures will mimic that of steroids. The chelate system with amide/amine/thioether/thiol donor sites failed to give a stable complex, but the corresponding diamine chelate gave a stable complex.
[Vasanthakumar, Ganga-Ramu; Patil, Basanagoud S.; Suresh Babu, Vommina V. Journal of the Chemical Society. Perkin Transactions 1, 2002 , # 18 p. 2087 - 2089]