Methyl 8-bromo-3-[1-(4-meth-oxy-phen-yl)-4-oxo-3-phenyl-azetidin-2-yl]-1-methyl-1,2,3,3a,4,9b-hexa-hydro-chromeno[4,3-b]pyrrole-3a-carboxyl-ate.

In the title compound, C30H29BrN2O5, the β-lactam ring is essentially planar, with the O atom displaced from this plane by 0.856 (9) Å, and forming dihedral angles of 24.35 (13) and 89.42 (14)° with the planes of the benzene substituent groups on this ring. The tetra-hydro-pyran ring adopts an envelope conformation with the C atom bearing the β-lactam ring as the flap. In the crystal, weak C-H⋯O hydrogen bonds with carboxyl and tetra-hydro-pyran O-atom acceptors give rise to a chain structure extending along the b-axis direction.