You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
2-(2,4-dichloro-6-methylphenoxy)-N-[3-([1,3]oxazolo[4,5-b]pyridin-2-yl)phenyl]acetamide is the IUPAC name of a molecule. Please give its molecular formula.
user
C21H15Cl2N3O3
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