Collect. Czech. Chem. Commun. 1997, 62, 1905-1918

Functionalization of Lupane-3β,28-diyl Diacetate with Chromium(VI) Oxide. Part 2

Jan Sejbala, Jiří Klinota, Miloš Buděšínskýb and Jiří Protivaa

a Department of Organic Chemistry, Charles University, 128 40 Prague 2, Czech Republic
b Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, 166 10 Prague 6, Czech Republic


Oxidation of lupane-3β,28-diyl diacetate (1) with chromium trioxide was reported already earlier to give small amounts of products functionalized in position 19β and 11 (19β-hydroxylupane-3β,28-diyl diacetate (3) and 11-oxolupane-3β,28-diyl diacetate (6)), together with products of subsequent oxidation, 21-oxolup-18-ene-3β,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-3β,28-diyl diacetate (8), 12-oxolupane-3β,28-diyl diacetate (9), 11-oxolup-12-ene-3β,28-diyl diacetate (17), 21-oxolupane-3β,28-diyl diacetate (20) and 16-oxolupane-3β,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 1H NMR, 13C NMR and mass spectroscopy.

Keywords: Triterpenes; Triterpenoids; Lupane derivatives; Oxidation; Functionalization; Chromium (VI) oxide.