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):
To be, or not to be to others that we know not of.<br> Aye that, O this conscience makes cowards of us all,<br> Lady in thy orizons, be all my sins remembered. The text of the Second Quarto (Q2) is considered the earliest version of the play. In Q2 the whole nunnery scene including 'To be' takes place later in the play than in Q1 where it occurs directly after Claudius and Polonius have planned it and the addition of "Soft you now", suggesting that Hamlet has not (or is feigning having not) seen Ophelia thus far during his speech. To be, or not to be,