TRITERPENES, PART CVIII - FUNCTIONALIZATION OF LUPANE-3-BETA,28-DIYL DIACETATE WITH CHROMIUM(VI) OXIDE - PART 2

摘要

Oxidation of lupane-3 beta, 28-diyl diacetate (1) with chromium trioxide was reported already earlier to give small amounts of products functionalized in position 19 beta and 11 (19 beta-hydroxylupane-3 beta, 28-diyl diacetate (3) and 11-oxolupane-3 beta, 28-diyl diacetate (6)), together with products of subsequent oxidation, 21-oxolup-18-ene-3 beta, 28-diyl diacetate (4) and anhydride 5). Now we identified further products, arising by functionalization in positions 12, 16 and 21 (12-hydroxy-11-oxolup-12-ene-3 beta, 28-diyl diacetate (8), 12-oxolupane-3 beta, 28-diyl diacetate (9), 11-oxolup-12-ene-3 beta, 28-diyl diacetate (17), 21-oxolupane-3 beta, 28-diyl diacetate (20) and 16-oxolupane-3 beta, 28-diyl diacetate (22)), either as such or after conversion into other derivatives. The obtained compounds were further transformed and structure of the prepared derivatives was confirmed by H-1 NMR, C-13 NMR and mass spectroscopy. [References: 16]