You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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For the molecule named 3-[4-[(6-chloro-2,3-dihydro-1,3-benzothiazol-2-yl)amino]phenyl]-[1,2,4]triazolo[4,3-a]pyrazine-8-carboxylic acid by IUPAC nomenclature, provide its molecular formula.
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C19H13ClN6O2S
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