Xanthatin, or (3aR,7S,8aS)-7-methyl-3-methylidene-6-[(E)-3-oxobut-1-enyl]-4,7,8,8a-tetrahydro-3aH-cyclohepta[b]furan-2-one (C15H18O3) is a major bioactive compound found in the leaves of the Xanthium strumarium (Asteracae) plant.
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