There has been considerable interest in the synthesis and biological properties of eunicellins as a result of their general cyctotoxic activity. This manuscript describes a concise synthesis of the tricyclic skeleton of key eunicellin analogues using an thermal Diels-Alder cycloaddition of a suitably functionalised 2,9-disubstituted oxonin derivative 3.16 (vide infra). (Fig. 11252A) The development of an organocatalytic Diels-Alder approach to the eunicellin core is also discussed, in which the endo/exo diastereoselectivity of the cycloaddition reaction is determined by the enantiomer of the organocatalyst used. (Fig. 11252B) This methodology represents a powerful way of gaining access to a remarkable family of compounds which exhibit microtubule stabilising properties which are comparable to those reported for paclitaxel^TM.