You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
N-methyl-N-[(3-methylpyridin-2-yl)methyl]-2-[(2S)-3-oxo-1-(thiophen-2-ylmethyl)piperazin-2-yl]acetamide is the IUPAC name of a molecule. Please give its molecular formula.
user
C19H24N4O2S
assistant