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 7-[1-[(2-amino-7H-purin-6-yl)amino]ethyl]-6-(2-chlorophenyl)-3-methyl-[1,3]thiazolo[3,2-a]pyrimidin-5-one into molecular formula.
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C20H17ClN8OS
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