You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Please write the molecular formula of the molecule ethyl (4R)-6-[[[(1S)-1-(3,4-difluorophenyl)ethyl]-methylamino]methyl]-4-methyl-2-oxo-3,4-dihydro-1H-pyrimidine-5-carboxylate .
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C18H23F2N3O3
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