In the title compound, C13H12O5, the mean plane of the 2H-chromene ring system (r.m.s deviation = 0.026 Å) forms a dihedral angle of 81.71 (6)° with the mean plane of ethyl 2-hy-droxy-acetate moiety (r.m.s deviation = 0.034 Å). In the crystal, C-H⋯O hydrogen bonds result in the formation of zigzag layers parallel to the bc plane.
In the title compound, C14H17N3O2, the mean plane of the 1,8-naphthyridine ring system (r.m.s deviation = 0.020 Å) forms a dihedral angle of 23.4 (1)° with the acetamide moiety (r.m.s deviation = 0.001 Å). The mol-ecular structure is stabilized by an intra-molecular O-H⋯N hydrogen bond, which generates an S(5) ring motif. In the crystal, mol-ecules are linked into inversion dimers by pairs of N-H⋯O hydrogen bonds, generating 18-membered R 2 (2)(18) ring motifs.
On the basis of the Förster resonance energy transfer mechanism between rhodamine and quinoline-benzothiazole conjugated dyad, a new colorimetric as well as fluorescence ratiometric probe was synthesized for the selective detection of Cd(2+). The complex formation of the probe with Cd(2+) was confirmed through Cd(2+)-bound single-crystal structure. Capability of the probe as imaging agent to detect the cellular uptake of Cd(2+) was demonstrated here using living RAW cells.