You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Can you give the molecular formula of the molecule 3-(4-bromophenyl)-1-methyl-1-[2-[5-[(3-methylphenoxy)methyl]-1,2,4-oxadiazol-3-yl]ethyl]urea ?
user
C20H21BrN4O3
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