| Abstract: | Twenty-two new limonoids, mufolinoids A—V (1—22), including six rings A, B-seco limonoids (1—6), twelve ring A-seco limonoids (7—18), four ring-intact limonoids (19—22), together with thirteen known compounds (23—35) were isolated from Munronia unifoliolata. Their structures including absolute configurations were elucidated by combination of NMR, HR-MS, single-crystal X-ray diffraction and calculations of ECD and NMR technologies. Compounds 24, 25, 33, 34 could be significantly reversed the multidrug resistance of MCF-7/doxorubicin (DOX) cells, and the reversal fold (RF) was much higher than that of positive drug Verapamil. Compounds 24, 28, and 29 exhibited significant anti-inflammatory activity with the IC50 values in the range of 17.7—39.4 μmol/L. Furthermore, compound 29 could markedly inhibit the release of IL-1β by inhibiting the initiation and assembly of NLRP3 inflammasome, which demonstrates the great potential of limonoids as an anti-inflammatory agent. |
