Two new sesquiterpene polyol esters from the root barks of Celastrus angulatus

Angulatin F (1) and angulatin I (2), two new sesquiterpene polyol esters, were isolated from the root barks of Celastrus angulatus, together with six known compounds 1β,2β-diacetoxy-4α,6α-dihydroxy-8α-isobutanoyloxy-9β-benzoyloxy-15-(α-methyl) butanoyloxy-β-dihydroagrofuran (3), angulatin A (4), angulatin B (5), celangulatin E (6), 1β,2β,15-triacetoxy-4α,6α-dihydroxy-8α-isobutanoyloxy-9β-benzoyloxy-β-dihydroagrofuran (7), and celangulin I (8). The structures of 1 and 2 were elucidated as 1β,2β,6α,15-tetraacetoxy-4α-hydroxy-8β,9α-difuroyloxy-β-dihydroagrofuran and 1β,2β,6α,8β,15-pentaacetoxy-4α-hydroxy-9β-furoyloxy-β-dihydroagrofuran by spectroscopic means.