In the title ep-oxy monomer, C(24)H(22)O(5), the dihedral angle in the biphenyl residue is 3.34 (19)°, indicating a nearly coplanar conformation; this residue is not planar with the adjacent benzene ring [dihedral angle = 58.93 (14)°]. Each of the epoxide rings is disordered. Each epoxide ring was resolved over two alternative positions with site-occupancy ratios of 0.638 (10):0.362 (10) and 0.797 (9):0.203 (9).