You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Convert the IUPAC name of a molecule ethyl 2-[1-[[N-[3-(4-ethylpiperazin-1-yl)-2-methylpropyl]-N'-methylcarbamimidoyl]amino]ethyl]-4-methyl-1,3-thiazole-5-carboxylate into molecular formula.
user
C21H38N6O2S
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