You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
For the molecule named 5-[4-[1-[6-(5-chloropyrazin-2-yl)imidazo[2,1-b][1,3,4]thiadiazol-2-yl]oxyethyl]piperidin-1-yl]-3-propan-2-yl-1,2,4-oxadiazole by IUPAC nomenclature, provide its molecular formula.
user
C20H23ClN8O2S
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