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 2-N-(2,6-dimethylphenyl)-5-methyl-7-N-(4-methylphenyl)-[1,3]thiazolo[5,4-d]pyrimidine-2,7-diamine into molecular formula.
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C21H21N5S
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