Chemical constituents of the stem bark of Morus cathayana.

Phytochemical investigation of the stem bark of Morus cathayana led to the isolation and identification of six new compounds, cathayanons F-J (1-5) and cathayanin A (6), and two known compounds, cathayanins B-C (7-8). Their structures were elucidated by spectroscopic methods. Compounds 1, 2, 3, 5, and 7 exhibited weak activities against five human cancer cell lines, with IC(50) values ranging from 4.7 to 9.8 microg/ml.