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What is the molecular formula of the molecule S-[(3S,6R,8aS)-8a-acetylsulfanyl-7-cyano-6-(6-methoxypyridin-3-yl)-2-methyl-1,4-dioxo-3,6,7,8-tetrahydropyrrolo[1,2-a]pyrazin-3-yl] ethanethioate ?
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C19H20N4O5S2
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