A stereoselective route to the spirobicyclic ring system of oscillatoxin D
摘要:
Using a model system, a stereoselective assembly of the 1-oxaspiro[5.5]undec-4-ene-8-one ring system of the antileukemic natural products oscillatoxin D and 30-methyloscillatoxin D was demonstrated. A key step was an intramolecular attack of the C1-C3 beta-ketoester enol on a silyl-activated 2,3-dihydro-4-pyranone to create a silyloxy analogue of the natural product's spirobicyclic ring system.