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What is the molecular formula of the molecule 7-[(2-bromoacetyl)amino]-3-[[1-[[1-[2-(3-fluoro-4-hydroxyanilino)-2-oxoethyl]pyridin-1-ium-4-yl]methyl]-2-oxopyrrolidin-3-ylidene]methyl]-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic acid ?
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C28H26BrFN5O7S+
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