Ciliatonoids A and B, Two Limonoids from Toona ciliata

Three new ring B-seco limonoids, ciliatonoids A–C (1–3), were isolated from Toona ciliate and structurally characterized by spectroscopic data, X-ray crystallography, and electronic circular dichroism analysis. Ciliatonoids A and B feature an unprecedented limonoid architecture, while ciliatonoid C belongs to a rare class of limonoids. Biological evaluation showed that compound 3 exhibited modest activities against the tested tumor cell lines.