Sesquiterpenoids from Common Ragweed (Ambrosia artemisiifolia L.), an Invasive Biological Polluter

Allergy to common ragweed (Ambrosia artemisiifolia L.) is increasingly important from a clinical standpoint, but surprisingly, little is known on the secondary metabolites of this plant and their potential involvement in the severity of the allergic reactions induced by its pollen. Along with known compounds, eight novel sesquiterpenoids were isolated from the aerial parts of A. artemisiifolia, evidencing the presence of large amounts of electrophilic a,beta-unsaturated carbonyl derivatives. Because compounds of this type were also present in pollen, their reactivity with thiols was investigated and correlated to the activation of TRPA1, a polymodal sensor highly expressed in the aerial pathways and involved in airways sensory irritation, a common complication of allergy to Ambrosia.