You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Under IUPAC nomenclature, a molecule named 5-[[(2R,3S)-2-[1-(4-fluorophenyl)pyrazol-4-yl]-1-methyl-5-oxopyrrolidin-3-yl]methylamino]pyrazine-2-carbonitrile is given. What is its corresponding molecular formula?
user
C20H18FN7O
assistant