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system
Name the molecular formula for the molecule established as 2-[3-(2-methylpropyl)-2,4-dioxo-4aH-thieno[3,2-d]pyrimidin-1-ium-1-yl]-N-(3,4,5-trimethoxyphenyl)acetamide using the IUPAC nomenclature.
user
C21H26N3O6S+
assistant