“…First, it led to the synthesis of compounds with greatly improved insecticidal activity, although sadly their toxicological profile prohibited practical use. 13 Furthermore, with this methodology, a functionally active ionophoric X-206 may now be covalently attached to fluorescent or radioactive markers, photoaffinity labels, proteins, and solid phases. Because of the large number of functional groups in ionophores, the means of reacting selectively and extraperipherally is all important.…”