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What is the molecular formula of the molecule 1-[(5S,8aS)-7-[(2-amino-1,3-benzothiazol-4-yl)methyl]-5-[(4-fluorophenyl)methyl]-3,6-dioxo-2,5,8,8a-tetrahydroimidazo[1,2-a]pyrazin-1-yl]-3-butyl-1-(cyanomethyl)urea ?
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C28H31FN8O3S
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