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What is the molecular formula of the molecule 3-[5-[[(3S,3'R,4'S,5'S,6'R)-6-chloro-3',4',5'-trihydroxy-6'-methylspiro[1H-2-benzofuran-3,2'-oxane]-5-yl]methyl]thiophen-2-yl]propanoate ?
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C21H22ClO7S-
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