【摘 要】
：
Mufolinin A (1),a ring A-seco rearranged limonoid with an unprecedented ethyl at C-10 and novel 6/6/6/5 fused-ring skeleton,together with three new potential precursors (ring A-seco limonoids,2-4) were iso-lated from Munronia unifoliolata.Their structures
【机 构】
：
Jiangsu Key Laboratory of Bioactive Natural Product Research and State Key Laboratory of Natural Med
论文部分内容阅读
Mufolinin A (1),a ring A-seco rearranged limonoid with an unprecedented ethyl at C-10 and novel 6/6/6/5 fused-ring skeleton,together with three new potential precursors (ring A-seco limonoids,2-4) were iso-lated from Munronia unifoliolata.Their structures and absolute configurations were confirmed by nuclear magnetic resonance (NMR),high resolution electrospray ionization mass spectroscopy (HRESIMS),X-ray crystallography,electronic circular dichroism (ECD) calculations and NMR calculations with DP4+ analy-ses.The unprecedented ethyl group of 1 was hypothesized to be derived from methyl migration and ring reduction rearrangement of ring A-seco limonoid 4.Compounds 2 and 4 showed significant multidrug resistance (MDR) reversal activities in MCF-7/DOX cells with reversal fold (RF) values of 13.1 and 8.0,respectively.
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