You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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For the molecule named 2-amino-3-[[2-amino-3-[8-butan-2-yl-2-(2-methoxyphenyl)-6,8-dihydro-5H-imidazo[1,2-a]pyrazin-7-yl]-3-oxopropyl]disulfanyl]-1-[8-butan-2-yl-2-(2-methoxyphenyl)-6,8-dihydro-5H-imidazo[1,2-a]pyrazin-7-yl]propan-1-one by IUPAC nomenclature, provide its molecular formula.
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C40H54N8O4S2
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