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What is the molecular formula of the compound with this IUPAC name sodium;(2R,7S,8S)-4-anilino-9-oxo-8-[(2-thiophen-2-ylacetyl)amino]-6-thia-1,3-diazabicyclo[5.2.0]non-3-ene-2-carboxylate ?
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C19H17N4NaO4S2
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