Intramolecular Diels–Alder route to angularly oxygenated hydrindanes. Synthesis of the functionalized bicylic skeleton present in galiellalactone

Intramolecular Diels–Alder reaction of trienones embedded in a sugar derivative with or without Me substituents on the diene part has been investigated for synthesis of hydrindanes with angular oxygen functionality. One of these adducts has been transformed to a functionalized bicyclic skeleton present in galiellalactone.