1',3',3'-Trimethyl-2,3-diphenyl-2,3-di-hydro-isoxazole-5(4H)-spiro-2'-indoline.

Two diastereoisomers of the title compound, C(25)H(26)N(2)O, have been prepared by cyclo-addition between 1,3,3-trimethyl-2-methyl-eneindoline and C-phenyl-N-phenyl-nitrone. The stereochemistry of the major diastereoisomer, viz. S,R/R,S, is confirmed by the X-ray analysis. The oxazole and the pyrole rings have envelope conformations. The packing is stabilized by weak C-H⋯π inter-actions involving the phenyl ring attached to the N atom of the oxazole and the phenyl ring of the indole fragment.