You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
For the molecule named 5-(4-methylpiperazin-1-yl)sulfonyl-N-[[2-(propoxymethyl)phenyl]methyl]pyridin-2-amine by IUPAC nomenclature, provide its molecular formula.
user
C21H30N4O3S
assistant