You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Convert the IUPAC name of a molecule N-[(2R,7S)-4-amino-2,5-dimethyl-6,6-dioxo-6lambda6-thia-3,5-diazatricyclo[9.4.0.02,7]pentadeca-1(11),3,12,14-tetraen-14-yl]-5-methoxypyrazine-2-carboxamide into molecular formula.
user
C20H24N6O4S
assistant