ACTA CRYSTALLOGRAPHICA SECTION E-CRYSTALLOGRAPHIC COMMUNICATIONS, vol.77, pp.247-257, 2021 (ESCI)
In the title compound, C27H33NO5, a 3,3,6,6-tetramethyltetrahydroacridine-1,8-dione ring system carries an ethyl acetate substituent on the acridine N atom and an o-hydroxyphenyl ring on the central methine C atom of the dihydropyridine ring. The benzene ring is inclined to the acridine ring system at an angle of 80.45 (7)degrees and this conformation is stabilized by an intramolecular O-H center dot center dot center dot O hydrogen bond between the hydroxy substituent on the benzene ring and one of the carbonyl groups of the acridinedione unit. The ester C=O oxygen atom is disordered over major and minor orientations in a 0.777 (9):0.223 (9) ratio and the terminal -CH3 unit of the ethyl side chain is disordered over two sets of sites in a 0.725 (5): 0.275 (5) ratio. In the crystal, C-H center dot center dot center dot O hydrogen bonds combine to link the molecules into a three-dimensional network. van der Waals H center dot center dot center dot H contacts contribute the most to the Hirshfeld surface (66.9%) followed by O center dot center dot center dot H/H center dot center dot center dot O (22.1%) contacts associated with weak hydrogen bonds.