Total synthesis of actinobolin from d-glucose by way of the stereoselective three-component coupling reaction

The total synthesis of (-)-actinobolin 3, an antipode of the natural product, starting from d-glucose is described. A three-component coupling reaction of functionalized cyclohexenone (+)-6 derived from d-glucose by way of Ferrier's carbocyclization reaction, with vinyl cuprate and 2-alkoxypropanal 7 effectively constructed the carbon framework of 3 in a highly stereoselective manner. In an aldol process of the three-component coupling reaction, stereochemical control (chelation and Felkin-Anh conditions) was achieved by the choice of the protecting groups of a hydroxy function in 2-hydroxypropanal and the reaction solvents. The formal synthesis of the natural enantiomer, (+)-actinobolin 1, starting from d-glucose was also accomplished.