Synthetic studies towards ergot alkaloids.

Some of the background to the biosynthesis, synthesis and uses of ergot alkaloids has been reviewed.A novel synthesis of the indole system has been used in an attempt to synthesise a derivative of the tricyclic Uhles ketone. A variation on this method has been carried out using 3-indole propionic acid as the starting material. The novel synthesis of the indole ring system has been developed into a synthesis of a 4-substituted indole.A number of literature methods for the synthesis of 4-substituted indoles have been investigated, and their usefulness in the laboratory assessed. A modified Reissert synthesis has been carried out, along with a Batcho-Leimgruber synthesis. Also the use of a thallium based method and palladium catalysed carbon-carbon bond formation have been investigated.A novel synthesis of p-benzoquinones has been discovered, by oxidation of aromatic sulphonamides. This method has not been optimised but low to moderate yields of quinones have been achieved. This method was used in an attempt to synthesise o-benzoquinones, but was found to be unsuitable.A novel synthesis of aromatic thiol esters has been developed starting from simple substituted benzaldehydes esters and methylmethylthiomethylsulphoxide. The resulting ketene thioacetal monosulphoxide was treated under the same conditions as those used in the novel indole synthesis. High yields of thiolesters were obtained.