Licochalcone B (LCB) inhibits the proliferation of human malignant bladder cancer cell lines (T24 and EJ) in vitro and antitumor activity in vivo in MB49 (murine bladder cancer cell line) tumor model. LCB and Licochalcone D(LCD) significantly reduced the LPS-induced production of NO, TNFalpha and MCP-1. A novel LCB derivative compound: (E)-3-(3, 4-dihydroxy-2-methoxyphenyl)-1-(2, 4-dihydroxyphenyl)prop-2-en-1-one inhibits inflammatory reactions in macrophages and protects mice from endotoxin shock.