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system
Name the molecular formula for the molecule established as 1'-[(3-chlorophenyl)methyl]-2-[(2-methyl-1,3-thiazol-4-yl)methyl]spiro[6,7-dihydropyrrolo[2,1-c][1,2,4]triazine-8,3'-pyrrolidine]-3,4-dione using the IUPAC nomenclature.
user
C21H22ClN5O2S
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