You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Provide the molecular formula for the IUPAC named substance 2-(6-amino-2-methyl-1,3-benzothiazol-5-yl)-1,3,4,7,8,8a-hexahydropyrrolo[1,2-a]pyrazin-6-one .
user
C15H18N4OS
assistant