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 (Z)-N-[2-(6-oxo-4-propyl-1H-pyrimidin-2-yl)-5-thiophen-2-ylpyrazol-3-yl]but-2-enamide .
user
C18H19N5O2S
assistant