title: Ethyl 4-methyl-1,3-dioxo-1,2,3,4-tetra-hydro-isoquinoline-4-carboxyl-ate.
abstract: In the title compound, C(13)H(13)NO(4), the fused-ring system is nearly planar, with an r.m.s. deviation of 0.0408 Å. In the crystal, mol-ecules are linked into centrosymmetric dimers by a pair of N-H⋯O hydrogen bonds. The ethyl group is disordered over two positions in a ratio of 0.758 (6):0.242 (6).
authors.affiliation: Laboratory of Asymmetric Catalysis and Synthesis, Department of Chemistry, Zhejiang University, Hangzhou 310027,  People's Republic of China.
authors.forename: Xing-Yao
authors.initials: XY
authors.lastname: Li
authors.forename: Jin-Long
authors.initials: JL
authors.lastname: Wu