You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
5-[(1S)-1-imidazol-1-ylethyl]-3-methyl-2-thiophen-2-yl-1H-pyrazolo[1,5-a]pyrimidin-7-one The above is the IUPAC name of a molecule. Write its molecular formula.
user
C16H15N5OS
assistant