You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
2-methyl-6-(propanoylamino)-N-[(1R)-1-[3-(trifluoromethyl)phenyl]ethyl]pyridine-4-carboxamide is the IUPAC name of a molecule. Please give its molecular formula.
user
C19H20F3N3O2
assistant