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 4-[[(8aR)-5,8-dioxo-1,3,6,8a-tetrahydro-[1,3]thiazolo[3,4-a]pyrazin-7-yl]methyl]-N-[(1S)-1-phenylethyl]benzamide .
user
C22H23N3O3S
assistant