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system
Name the molecular formula for the molecule established as (5-chloro-2-methoxyphenyl)methyl (3S,7aS)-5-oxo-7a-phenyl-2,3,6,7-tetrahydropyrrolo[2,1-b][1,3]thiazole-3-carboxylate using the IUPAC nomenclature.
user
C21H20ClNO4S
assistant