You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
3-(2,4-dimethylphenyl)-1-[2-[4-(4-fluorophenyl)-4H-pyrrolo[1,2-a]quinoxalin-5-yl]-2-oxoethyl]-1-propan-2-ylurea The above is the IUPAC name of a molecule. Write its molecular formula.
user
C31H31FN4O2
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