Crystal structure and Hirshfeld surface analysis of N-(2,6-di-methyl-phen-yl)-2-[3-hy-droxy-2-oxo-3-(2-oxoprop-yl)indolin-1-yl]acetamide.

The cup-shaped conformation of the title mol-ecule, C(21)H(22)N(2)O(4), is largely determined by an intra-molecular N-H⋯O hydrogen bond. In the crystal, double layers of mol-ecules are formed by O-H⋯O and C-H⋯O hydrogen bonds. A Hirshfeld surface analysis was performed, which confirms the regions that are active for inter-molecular inter-actions.