You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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For the molecule named (2R)-2-[[(3R,4S,5S,6R)-5-methoxy-4-[(2S,3S)-2-methyl-3-(3-methylbut-2-enyl)oxiran-2-yl]-1-oxaspiro[2.5]octan-6-yl]oxycarbonylamino]-3-methylbutanoic acid by IUPAC nomenclature, provide its molecular formula.
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C22H35NO7
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