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What is the molecular formula of the molecule identified by potassium;(6S)-4-(2,2-dicyanoethyl)-7-[[2-(furan-2-yl)acetyl]amino]-3-methyl-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylate ?
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C18H15KN4O5S
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