You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
1-(3,5-dichloropyridin-4-yl)-4-methoxy-2-[(1S)-3-methoxy-1-phenylpropyl]benzimidazole The above is the IUPAC name of a molecule. Write its molecular formula.
user
C23H21Cl2N3O2
assistant