You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Translate the chemical IUPAC name 1-[2-(1-benzothiophen-2-yl)-2-hydroxyethyl]-3-[(5-tert-butyl-1,3-oxazol-2-yl)methyl]-2-methylguanidine into its molecular formula.
user
C20H26N4O2S
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