You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
1-[(3R)-3-[4-(3-chloro-2-fluoroanilino)-7-methoxyquinazolin-6-yl]oxypiperidin-1-yl]-2-thiophen-3-ylethanone The above is the IUPAC name of a molecule. Write its molecular formula.
user
C26H24ClFN4O3S
assistant