Crystal structure of ethyl (4R)-2-amino-7-hy-droxy-4-phenyl-4H-chromene-3-carboxyl-ate.

In the title compound, C18H17NO4, the dihedral angle between the phenyl ring and the fused six-membered ring is 77.65†(4)°. The conformation of the mol-ecule is determined in part by an intra-molecular N-H⋯O hydrogen bond between the amino H atom and the carbonyl O atom, forming an S(6) motif. In the crystal, mol-ecules are linked into N-H⋯O hydrogen-bonded inversion dimers which are then connected into chains along [001], forming a two-dimensional network parallel to (100) via O-H⋯O hydrogen bonds. C-H⋯O interactions further contribute to the crystal stability. The ethyl group is disordered over two sets of sites in a 0.801†(5):0.199†(5) ratio.