You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Convert the IUPAC name of a molecule 1-[2-(4-methoxyphenoxy)ethylsulfonyl]-4-propan-2-yl-[1,2,4]triazolo[4,3-a]benzimidazole into molecular formula.
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C20H22N4O4S
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