3-(2,5-Di-methyl-phen-yl)-8-meth-oxy-2-oxo-1-aza-spiro-[4.5]dec-3-en-4-yl 3-(2-bromo-4-fluoro-phen-yl)acrylate.

In the title compound, C27H27BrFNO4, which is an inhibitor of acetyl-CoA carboxyl-ase, the cyclo-hexane ring displays a chair comformation with the spiro-C and meth-oxy-bearing C atoms deviating by 0.681 (7) and -0.655 (1) Å, resppectively, from the mean plane formed by the other four C atoms of the spiro-C6 ring. The mean planes of the cyclo-hexane and 2-bromo-4-fluoro-phenyl rings are nearly perpendicular to that of the pyrrolidine ring, making dihedral angles 89.75 (6) and 87.60 (9)°, respectively. In the crystal, mol-ecules are linked via pairs of N-H⋯O hydrogen bonds, forming inversion dimers.

(1'S,4'S)-5-(2,5-Dimethyl-phen-yl)-4'-meth-oxy-6-oxa-3-aza-spiro-[bicyclo-[3.1.0]hexane-2,1'-cyclo-hexa-n]-4-one.

In the title compound, C18H23NO3, the cyclo-hexane ring has a chair conformation. The oxirane plane (OCC) makes a dihedral angle of 76.15 (13)° with that of the pyrrolidine ring to which it is fused. The mean plane of the cyclo-hexane ring and the benzene ring are almost normal to the pyrrolidine ring, with dihedral angles of 88.47 (8) and 77.85 (8)°, respectively. In the crystal, mol-ecules are linked via pairs of N-H⋯O hydrogen bonds, forming inversion dimers. These dimers are linked via pairs of C-H⋯O hydrogen bonds, forming chains along the a-axis direction.