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What is the molecular formula of the molecule identified by tert-butyl (6R)-7-[[2-(furan-3-yl)acetyl]amino]-3-(2-methylpropanoyl)-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylate ?
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C21H26N2O6S
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