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system
What is the molecular formula of the molecule propan-2-yl (6S,9aS)-6-butyl-8-(3-methylbutyl)-4,7-dioxospiro[2,6,9,9a-tetrahydropyrazino[1,2-a]pyrimidine-3,1'-cyclohexane]-1-carboxylate ?
user
C25H43N3O4
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