Novel arneomas A-B and other naphthoquinone active components in <i>Arnebia euchroma</i> I. M. Johnst

<i>Arnebia euchroma</i> I. M. Johnst., a famous traditional medicine in China, is widely used in TCM clinic. As the purpose to dig bioactive constituents, silica gel, preparative High-Performance Liquid Chromatography and other manners were used to analyse its components. As a result, two new compounds arneomas A-B (<b>1-2</b>), and four known ones deoxyalkannin (<b>3</b>), shikonin (<b>4</b>), arnebifuranone (<b>5</b>), heliotropin one A (<b>6</b>) were obtained. Their structures were determined by spectral data and physical and chemical properties. The CCK-8 method was used to assess the cytotoxicity of the compounds towards the human cervical cancer cell line (Hela cells). Compounds <b>2</b> and <b>4</b> show apparent antitumor activity with median inhibition concentration IC₅₀ of 6.07, 8.37 μM.