You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Convert the IUPAC name of a molecule 1-[4-amino-5-(azetidine-1-carboximidoyl)pyridin-2-yl]-3-[(1R)-1-phenylethyl]urea;molecular hydrogen into molecular formula.
user
C18H28N6O
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