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What is the molecular formula of the molecule identified by [(3aR,4R,6R,6aR)-1'-butyl-2,2-dimethyl-5'-oxo-2'-sulfanylidenespiro[6,6a-dihydro-3aH-furo[3,4-d][1,3]dioxole-4,4'-imidazolidine]-6-yl]methyl benzoate ?
user
C21H26N2O6S
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