Functionalization of 3β,28-lupanediol diacetate with chromium(VI) oxide

Abstract

The oxidation of 3β,28-lupanediol diacetate (I) with chromium(VI) oxide gives low yields of products with functional groups in the ring E as products of hydroxylation at the 19β position (IV, VI, and IX) and the 11-ketone VII which has been transformed into other lupane derivatives with an oxygen functional group at 11 position (VIII, XIII - XV) or with a 9(11)-double bond (XVI, XVII). Structure of the compounds prepared has been verified by their 1H and 13C NMR spectra as well as by their mass spectra.