You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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Convert the IUPAC name of a molecule 4-(2,5-dichlorophenyl)-3-[1-(4-methyl-3-nitrophenyl)ethylideneamino]-N-prop-2-enyl-1,3-thiazol-2-imine into molecular formula.
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C21H18Cl2N4O2S
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