You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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Under IUPAC nomenclature, a molecule named 1-[5-(4-butoxyphenyl)-1,3,4-thiadiazol-2-yl]-3-(2-fluorophenyl)urea is given. What is its corresponding molecular formula?
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C19H19FN4O2S
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