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What is the molecular formula of the molecule (2S)-N-[(3aS,6aS)-3-(3-butoxyphenyl)-5,5-dioxo-3a,4,6,6a-tetrahydrothieno[3,4-d][1,3]thiazol-2-ylidene]oxolane-2-carboxamide ?
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C20H26N2O5S2
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