Stereoselective ketal-tethered intramolecular Diels-Alder cycloadditions. An approach to the 2-oxadecalin spiroketal core of antifungal agent fusidilactione C

An approach toward the 2-oxadecalin spiroketal core of fusidilactone C via a rare ketal-tethered intramolecular Diels-Alder cycloaddition is described here. This intramolecular Diels-Alder cycloaddition is highly endo-selective and overall depended upon the nature of solvents and Lewis acids, We also observed some remarkable rate acceleration in MeOH.