You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
ethyl 4-[[2-[[5-(3,4,5-trimethoxyphenyl)-1,3,4-oxadiazol-2-yl]sulfanyl]acetyl]amino]butanoate is the IUPAC name of a molecule. Please give its molecular formula.
user
C19H25N3O7S
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