You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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For the molecule named (2S)-3-(7-carbamimidoylnaphthalen-2-yl)-2-[4-[(3S)-1-(cyanomethyl)pyrrolidine-3-carbonyl]phenyl]propanoic acid by IUPAC nomenclature, provide its molecular formula.
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C27H26N4O3
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