title: Ethyl 2-amino-7,7-dimethyl-2',5-dioxo-spiro-[5,6,7,8-tetra-hydro-4H-chromene-4,3'(2'H)-1H-indole]-3-carboxyl-ate.
abstract: In the mol-ecule of the title compound, C(21)H(22)N(2)O(5), the indole system and the spiro-pyran ring are almost planar [maximum deviations of 0.0447 (17) and 0.0781 (17) Å, respectively]; the dihedral angle between them is 84.6 (3)°. The remaining six-membered ring adopts a twisted conformation. Intra-molecular N-H⋯O hydrogen bonds occur. In the crystal structure, intera-molecular N-H⋯O and C-H⋯O hydrogen bonds link the mol-ecules.
authors.affiliation: Department of Chemistry, Xuzhou Medical College, Xuzhou 221004, People's Republic of China.
authors.forename: Jing
authors.initials: J
authors.lastname: Wang
authors.forename: Song-Lei
authors.initials: SL
authors.lastname: Zhu