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 (7R)-2-methyl-1'-(5-methylthiophene-2-carbonyl)spiro[6,8-dihydropyrrolo[2,1-c][1,2,4]triazine-7,3'-pyrrolidine]-3,4-dione .
user
C16H18N4O3S
assistant