| Abstract: | Six new butanolides, two with 1,2-dioxane moieties: litseadioxanin A (=rel-(2E,3S,4R)-dihydro-2-(10-(3,6-dihydro-1,2-dioxin-3-yl)decylidene)-3-hydroxy-4-methylfuran-1(3H)-one (1), litseadioxanin B (=rel- (2Z,3S,4R)-dihydro-2-(10-(3,6-dihydro-1,2-dioxin-3-yl)decylidene)-3-hydroxy-4-methylfuran-1(3H)-one (2), and another four: litseatrinolide A (=rel-(2E,3S,4R)-dihydro-3-hydroxy-2-((E)-11,14-dihydroxytetradec-12-enylidene)-4-methylfuran-1(3H)-one (3), litseatrinolide B (=rel-(2Z,3S,4R)-dihydro-3-hydroxy-2-((E)-11,14-dihydroxytetradec-12-enylidene)-4-methylfuran1-(3H)-one (4), litseakolide D1 (=(2Z,3S,4R)-dihydro-3-hydroxy-4-methyl-2-(tetradec-13-enylidene)furan-1(3H)-one (5), and litseakolide D2 (=(2E,3S,4R)-dihydro-3-hydroxy-4-methyl-2-(tetradec-13-enylidene)furan-1(3H)-one (6), were isolated from the stem bark of Litsea akoensis Hay. (Lauraceae), together with six known compounds (7-12). Their structures were characterized by in-depth NMR-spectroscopic and mass-spectrometric analyses. Butanolides 1-4, a mixture of 6 and 8, and 9 were tested against human tumor cells, including MCF-7 (human breast adenocarcinoma), NCI-H460 (non-small-cell lung cancer) and SF-268 (glioblastoma cells) cell lines. Among the isolates, litsenolide B1 (9) exhibited marginal cytotoxic activity against MCF-7, NCI-H460 and SF-268 cell lines in vitro. |
