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What is the molecular formula of the molecule identified by (6S)-8-[2-(4-fluorophenyl)ethyl]-2-methyl-6-(2-methylsulfanylethyl)-4,7-dioxo-3,6,9,9a-tetrahydropyrazino[2,1-c][1,2,4]triazine-1-carbaldehyde ?
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C19H25FN4O3S
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