You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
N-[(R)-(4-fluorophenyl)-(5-phenyl-1,3,4-oxadiazol-2-yl)methyl]-2-methylpropanamide is the IUPAC name of a molecule. Please give its molecular formula.
user
C19H18FN3O2
assistant