Synthesis of cryptophanes With Two Different Reaction Sites: Chemical Platforms for Xenon Biosensing

International audienceWe report the synthesis of new water-soluble cryptophane host molecules that can be used for the preparation of 129Xe NMR-based biosensors. We show that the cryptophane-223 skeleton can be modified in order to introduce a unique secondary alcohol to the propylenedioxy linker. This chemical functionality can then be exploited to introduce a functional group different from the six chemical groups attached to the aromatic rings. In this approach the generation of a statistical mixture when trying to selectively functionalize a symmetrical host molecule is eliminated, which enables the efficient large-scale production of new cryptophanes that can be used as chemical platforms ready to use for the preparation of xenon biosensors. To illustrate this approach molecular platforms 1 and 2 have been prepared. The ability of these new derivatives to bind xenon has also been investigated