You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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For the molecule named (4R)-2-amino-6-(furan-2-ylmethyl)-7-methyl-5-oxo-4-thiophen-2-yl-4H-pyrano[3,2-c]pyridine-3-carbonitrile by IUPAC nomenclature, provide its molecular formula.
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C19H15N3O3S
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