Limonoids with modified furan rings from root barks of Toona sinensis

Abstract Toonasinemines A–K ( 1 – 12 ), 12 new azadirone- and gedunin-type limonoids with eight-classes of modified furan rings, were isolated from the root barks of Toona sinensis (A. Juss.) Roem. Their structures were elucidated based on detailed spectroscopic analyses, and the absolute configurations of 1 – 9 were established by the electronic circular dichroism exciton chirality method. The lactam-bearing moieties in compounds 1 – 7 were rare in limonoids family. Results of bioactivities screening exhibited that 1 , 4 , and 8 showed moderate cytotoxicities against HepG2, MCF-7, and U2OS human cancer cell lines, and 1 , 2 , 6 , 8 , and 9 exhibited marked inhibitory effects on nitric oxide (NO) production in LPS-activated RAW 264.7 macrophages at nontoxic concentration.