You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
1-ethyl-3-(2-methyl-3-pyrazol-1-ylpropyl)-2-[(5-methylthiophen-2-yl)methyl]guanidine The above is the IUPAC name of a molecule. Write its molecular formula.
user
C16H25N5S
assistant