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What is the molecular formula of the molecule (4aR,8aS)-6-[(E)-3-(furan-2-yl)prop-2-enyl]-1-[2-(1H-imidazol-5-yl)ethyl]-4,4a,5,7,8,8a-hexahydro-3H-1,6-naphthyridin-2-one ?
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C20H26N4O2
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