Chapter 14: Ergot Alkaloids

Ergot alkaloids (EA, syn. ergoline alkaloids) are highly bioactive fungal-derived secondary metabolites. They are a group of structurally diverse l-tryptophan derivatives that share a common, so-called ergoline scaffold. Historically, ergots were infamous as they infected rye and other cereals, thereby causing ergotism in populations that consumed poisoned grain. This negative history has often overshadowed the beneficial properties of ergot alkaloids, which are used as drugs for many pharmacological purposes, such as migraines, Parkinson's disease and cancer. EA are found primarily in filamentous fungi, though these compounds have also been observed in the plant taxa Convolvulaceae, which is associated with Clavicipitaceous fungi. However, these plants are not the producers of EA, which are indeed seed transmitted by colonized Clavicipitaceous fungus. Recently, biosynthesis of EA has been extensively studied, both at the genomic and the biochemical levels, though the chemical mechanism of ergoline scaffold formation still remains unclear. The total synthesis of these complex molecules is of great interest to many organic chemists.