You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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Convert the IUPAC name of a molecule methyl 5,5,7,7-tetramethyl-2-(pentanoylamino)-4,6-dihydrothieno[2,3-c]pyridin-6-ium-3-carboxylate into molecular formula.
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C18H29N2O3S+
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