You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Convert the IUPAC name of a molecule N-[3-(2-ethylimidazol-1-yl)propyl]-5-(pyrimidin-2-ylsulfanylmethyl)furan-2-carboxamide into molecular formula.
user
C18H21N5O2S
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