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What is the molecular formula of the molecule identified by 3-[(2-amino-3-sulfanylpropanoyl)amino]-4-[[1-[(1-carboxy-3-methylsulfanylpropyl)amino]-3-(4-hydroxyphenyl)-1-oxopropan-2-yl]amino]-4-oxobutanoic acid ?
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C21H30N4O8S2
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