You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
For the molecule named N-methyl-N-(2-methyl-1,3-benzothiazol-6-yl)-2-(4-methylpiperazin-1-yl)pyridine-4-carboxamide by IUPAC nomenclature, provide its molecular formula.
user
C20H23N5OS
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