Ruta graveolens the isolation of the furanocoumarin chalepensin. The essential oil of "R. graveolens" contains two main constituents, undecan-2-one (46.8%) and nonan-2-one (18.8%). The bitter taste of its leaves led to rue being associated with the (etymologically unrelated) verb "rue" "to regret". Rue is well known for its symbolic meaning of regret and it has sometimes been called "herb-of-grace" in literary works. It is one of the flowers distributed by the mad Ophelia in William Shakespeare's "Hamlet" (IV.5): It was planted by the gardener in "Richard II" to mark the spot where the Queen wept upon hearing news of Richard's capture (III.4.104–105):
Hamlet (1948 film) poison into the late King Hamlet's ear, thereby killing him. Hamlet does not at first accept this as the truth, and then prepares to feign madness, so as to test Claudius' conscience, without jumping to conclusions. This feigned insanity attracts the attention of Polonius (Felix Aylmer) who is completely convinced that Hamlet has gone mad. Polonius pushes this point with the King, claiming that it is derived from Hamlet's love for Ophelia (Jean Simmons), Polonius's daughter. Claudius, however, is not fully convinced, and has Polonius set up a meeting between Hamlet and Ophelia. Hamlet's "madness" is constant even in this