You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
For the molecule named 2-chloro-N-[(2R)-6-methylheptan-2-yl]-5,5-dioxo-8,9,10,11-tetrahydro-7H-azepino[2,1-c][1,2,4]benzothiadiazine-3-carboxamide by IUPAC nomenclature, provide its molecular formula.
user
C21H30ClN3O3S
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