A Molecular Keypad Lock Based on the Thiacalix[4]arene of 1,3-Alternate Conformation

A chemosensor based on the thiacalix[4]arene of 1,3-alternate conformation has been designed and synthesized. The binding behavior of this chemosensor has been studied toward different metal ions by fluorescence spectroscopy, and it was observed that the chemosensor selectively senses Cu2+ ions. The chemical inputs of Cu2+ and F- in a sequential manner generate an output which mimics the functions of a security keypad lock.