Chiral anion recognition by color change utilizing thiourea, azophenol, and glucopyranosyl groups

A new colorimetric anion sensor 1 was synthesized for the chiral recognition, which accommodates a combination of three different functional groups such as chromophore (azophenol dye), binding site (thiourea group), and chiral barrier (glucopyranosyl group). The colorimetric changes of host 1 with various α-amino carboxylates as well as chiral carboxylates such as naproxen were examined.