You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
For the molecule named (5S)-1'-[4-(1,1-difluoroethyl)pyridin-2-yl]-5-phenylspiro[5,6,7,7a-tetrahydropyrrolo[2,1-b][1,3]oxazole-2,4'-piperidine]-3-one by IUPAC nomenclature, provide its molecular formula.
user
C23H25F2N3O2
assistant