New cytotoxic and anti-inflammatory compounds isolated from Morus alba L.

Six Diels–Alder adducts (1–6) and nine prenylated flavanones (7–15) were isolated from the root bark of Morus alba L. Among them, soroceal B (1) and sanggenol Q (7) were new compounds. Their structures were elucidated on the basis of extensive spectroscopic methods, including 1D and 2D NMR techniques. Compounds 1–3, 9, 10, 12, 13 and 15 exhibited cytotoxic activity against five human tumour lines and compound 2 inhibited significantly selective cytotoxic activities towards HL-60 and AGS cells with IC₅₀ of 3.4 and 3.6 μM. Compounds 3, 5, 9 and 12 exhibited moderate inhibitory activity against nitric oxide production in LPS-activated RAW264.7.