Cipadessains A-K, eleven limonoids from the fruits of Cipadessa cinerascens

Eleven new mexicanolide-type limonoids, cipadessains A-K (1-11), were isolated from the fruits of Cipadessa cinerascens (Pellegr) Hand.-Mazz. Their planar structures were determined based on IR, UV, 1D and 2D NMR spectra and HRESIMS data. The absolute configuration of 1 was elucidated by single-crystal X-ray diffraction using mirror Cu K radiation, and that of compounds 2-8 were determined by ECD analysis. Two mexicanolides bearing methoxybutenolide moiety originated from the furan ring 3 and 6, showed significant cytotoxicity against HepG2 cell line with IC50 values of 5.23 +/- 0.12, 8.67 +/- 1.02 M, respectively; and NO inhibitory activities in LPS-activated RAW 264.7 macrophages at nontoxic concentration (IC50 5.79 +/- 0.18, 6.93 +/- 0.89 M, respectively).