You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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Convert the IUPAC name of a molecule 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]-3-methyl-1-propan-2-ylurea into molecular formula.
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C27H33N7O4S
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