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What is the molecular formula of the compound with this IUPAC name 1-[(8aS)-7-[(2-amino-1,3-benzothiazol-4-yl)methyl]-3,6-dioxo-2,5,8,8a-tetrahydroimidazo[1,2-a]pyrazin-1-yl]-3-[(4-methoxyphenyl)methyl]-1-prop-2-ynylurea ?
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C26H27N7O4S
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