You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Convert the IUPAC name of a molecule methyl N-[5-(3-amino-2-cyclobutylsulfanyl-4-pyridin-3-ylthieno[2,3-b]pyridin-6-yl)pyridin-2-yl]carbamate into molecular formula.
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C23H21N5O2S2
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