You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
[2-(2-methylpropylcarbamoylamino)-2-oxoethyl] (2R)-3-methyl-2-(phenylcarbamoylamino)butanoate The above is the IUPAC name of a molecule. Write its molecular formula.
user
C19H28N4O5
assistant