You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Please write the molecular formula of the molecule (2R,3R,3aS,9bS)-1-(2-fluorobenzoyl)-3-(hydroxymethyl)-6-oxo-7-phenyl-N-propyl-3,3a,4,9b-tetrahydro-2H-pyrrolo[2,3-a]indolizine-2-carboxamide .
user
C28H28FN3O4
assistant