RESUMO
In the title compound, C21H21NO5, obtained from a Morita-Baylis-Hillman adduct, the hydrogenated five-membered ring adopts a shallow envelope conformation, with the C atom bearing the carb-oxy-lic acid substituent deviating by 0.237â (1)â Å from the mean plane of the other four atoms (r.m.s. deviation = 0.007â Å). The dihedral angle between the fused ring system (all atoms; r.m.s. deviation = 0.057â Å) and the pendant trimeth-oxy benzene ring is 66.65â (3)°. The C atoms of the meta-meth-oxy groups lie close to the plane of the benzene ring [deviations = 0.052â (1) and -0.083â (1)â Å], whereas the C atom of the para-meth-oxy group is significantly displaced [deviation = -1.289â (1)â Å]. In the crystal, carb-oxy-lic acid inversion dimers generate R 2 (2)(8) loops. The dimers are connected by N-Hâ¯O hydrogen bonds, forming [011] chains. A C-Hâ¯O inter-action is also observed.