You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
For the molecule named N-[2-(dimethylamino)ethyl]-N-(6-methyl-1,3-benzothiazol-2-yl)-2-(4-methylphenyl)sulfonylacetamide;hydrochloride by IUPAC nomenclature, provide its molecular formula.
user
C21H26ClN3O3S2
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