Cytotoxic Limonoids from the Twigs and Leaves of .

Eight new limonoids, toononoids A-H (-), eight new B--29-norlimonoids, toonanoronoids A-H (-), and seven known analogues were obtained from the EtOAc extract of the twigs and leaves of . Compounds , , , and are rare lactam-bearing limonoids. Compounds , , and possess an unusual γ-methoxybutenolide moiety at C-17, while compounds , , and have a rare 3β-hydroxy group. Their 2D structure and relative configurations were identified using spectroscopic data. The absolute configurations of , , , and were established via X-ray diffraction crystallography or comparison of experimental and calculated ECD data. The cytotoxicity of the compounds was assessed toward five human tumor cell lines, and their anti-inflammatory activity was assessed based on NO production using LPS-stimulated RAW264.7 macrophages. Compounds and exerted inhibition toward two tumor cell lines (MCF-7, SW-480) with IC values between 2.1 and 3.7 μM, while - inhibited the proliferation of HL-60, MCF-7, and SW-480 cells (IC 0.6-4.0 μM). Only compound exhibited weak anti-inflammatory activity with an IC value of 28.3 μM.