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system
Name the molecular formula for the molecule established as 3-[(5Z)-5-[(4-ethyl-2,3,3a,8b-tetrahydro-1H-cyclopenta[b]indol-7-yl)methylidene]-4-oxo-2-sulfanylidene-1,3-thiazolidin-3-yl]propanoic acid using the IUPAC nomenclature.
user
C20H22N2O3S2
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