You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Convert the IUPAC name of a molecule 3-amino-6-(2-anilinoethylamino)-5-cyano-4-thiophen-2-ylthieno[2,3-b]pyridine-2-carboxamide into molecular formula.
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C21H18N6OS2
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