Rare flavonoids and sesquiterpenoids isolated from the leaves of Goniothalamus gracilipes.

Three previously undescribed benzopyranyl sesquiterpenes gracilipins BD (1-3) and two flavonoids 5,4'-dihydroxy-6-(2-hydroxybenzyl)-3,7,3'-trimethoxyflavone (4), and 5,4'-dihydroxy-8-(2-hydroxybenzyl)-3,7-dimethoxyflavone (5) were isolated from the leaves of Goniothalamus gracilipes (Annonaceae). Their structures were determined by analyses of MS and 2D NMR data. The absolute configurations of 1 were established by analysis of X-ray diffraction data. Cytotoxic evaluation of the compounds 1-5 against four cancer cell lines (KB, LU-1, HepG-2 and MCF-7) indicated that compound 5 had inhibitory activity against HepG-2 cell line with IC50 value of 16.7 µM. All new compounds (1-5) were evaluated for their antimicrobial activity against a panel of clinically significant microorganisms. Compound 2 showed significant antimicrobial effect on Staphylococus aureus with MIC value of 32 µg/mL.

Styryllactones and acetogenins from the fruits of Goniothalamus macrocalyx.

Two new styryllactones, macrocalactone (1) and 3-deoxycardiobutanolide (2), were isolated from the fruits of Goniothalamus macrocalyx Ban (Annonaceae), together with seven known compounds including four acetogenins, annonacin (3), solamin (4), isoannonacin (5), trans-murisolinone (6), and three other compounds, 7-acetylaltholactone (7), beta-caryophyllene-8R,9R-oxide (8) and 2-(2'-hydroxytetracosanoylamino)-octadecane-1,3,4-triol (9). Their structures were determined by spectroscopic and MS analysis. The absolute configuration of 1 was determined by X-ray crystallographic analysis. The structures of the acetogenins were confirmed by liquid chromatography coupled to a hybrid quadrupole-time of flight mass spectrometer, using post-column lithium infusion. The results were compared with the fragmentation obtained with a hybrid linear trap-orbitrap mass spectrometer. Compound 7 had cytotoxicity against KB, HepG2, Lu, and MCF7 cell lines with IC50 values of 13.1, 23.7, 26.3 and 60.2 microM, respectively, whereas annonacin (3) was selectively active against KB cells (IC50 value of 6.5 microM). The discovery of 3-deoxycardiobutanolide (2) from the fruits of this plant revealed that G. macrocalyx could be a valuable natural resource to obtain this compound as it has been previously reported to have a significant cytotoxicity against different cancer cell lines, especially HL-60 cells.