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system
Name the molecular formula for the molecule established as (2E,6R)-2-[(E)-1-(3-fluoro-4-methoxyphenyl)ethylidenehydrazinylidene]-N-(2-methoxyphenyl)-4-oxo-1,3-thiazinane-6-carboxamide using the IUPAC nomenclature.
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C21H21FN4O4S
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