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What is the molecular formula of the compound with this IUPAC name (13S)-13-ethyl-3,3,20,20-tetramethyl-19-(methylamino)-6,9,12,15,18-pentaoxo-1,2-dithia-5,8,11,14,17-pentazacycloicosane-4-carboxamide ?
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C21H37N7O6S2
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