Key indicators: single-crystal X-ray study; T = 293 K; mean (C-C) = 0.003 Å; R factor = 0.045; wR factor = 0.133; data-to-parameter ratio = 14.6.In the title compound, C 28 H 22 O 6 , the chromeno ring system is almost planar, with a dihedral angle between the mean planes of the pyran and benzene rings of 1.87 (8) . The pyran ring bearing the methylphenyl substituent has a half-chair conformation while the other pyran ring has an envelope conformation with the tetrasubstituted C atom as the flap. The benzene ring of the chromeno ring system is inclined to the benzene ring fused to the latter pyran ring by 74.66 (9) . These aromatic rings are inclined to the 4-methylphenyl ring by 52.67 (9) and 66.63 (10) , respectively. In the crystal, molecules are linked via C-HÁ Á ÁO hydrogen bonds, forming a two-dimensional network parallel to the bc plane.
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