Cytotoxic Diarylheptanoids from the Roots of <i>Juglans </i><i>m</i><i>andshurica</i>

A new (<b>2</b>) and three known diarylheptanoids (<b>1</b>, <b>3</b>, and <b>4</b>), along with one known sesquiterpenoid (<b>5</b>), were isolated from the roots of <i>Juglans mandshurica</i>, and their structures were elucidated on the basis of spectroscopic studies. Four of these compounds (<b>2</b>−<b>5</b>) exhibited moderate cytotoxicities against human colon carcinoma and human lung carcinoma cell lines with IC<sub>50</sub>'s ranging from 2 to 25 μg/mL.