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system
Name the molecular formula for the molecule established as methyl (1R,3S,3aR,6aS)-5-ethyl-3-[(4-hydroxyphenyl)methyl]-4,6-dioxo-1-thiophen-2-yl-1,2,3a,6a-tetrahydropyrrolo[3,4-c]pyrrole-3-carboxylate using the IUPAC nomenclature.
user
C21H22N2O5S
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