Aminopyridine−Benzoxanthene Enantioselective Receptor for Sulfonylamino Acids

Combination of a cis-tetrahydrobenzoxanthene skeleton with a benzoxazole and an amidopyridine provides an enantioselective receptor for
sulfonylamino acids with chiral recognitions of up to 18. The structure of the complex between receptor 1 and the leucine triflate is known
by X-ray analysis. The receptor racemic mixture can be suitably resolved through crystalization in the presence of leucine triflate as guest.
Receptor 1 can be used for the enantioselective extraction of sulfonylamino acids from aqueous solutions of their salts.