10.6084/m9.figshare.2068809 Suda Chakthong Suda Chakthong Nitima Bindulem Nitima Bindulem Sirorat Raknai Sirorat Raknai Sariya Yodwaree Sariya Yodwaree Soonthorn Kaewsanee Soonthorn Kaewsanee Akkharawit Kanjana-Opas Akkharawit Kanjana-Opas Carbazole-pyranocoumarin conjugate and two carbazole alkaloids from the stems of <i>Clausena excavata</i> Taylor & Francis Group 2016 Clausena excavata carbazole alkaloids Rutaceae cytotoxic activity 2016-01-30 00:45:33 Journal contribution https://tandf.figshare.com/articles/journal_contribution/Carbazole_pyranocoumarin_conjugate_and_two_carbazole_alkaloids_from_the_stems_of_i_Clausena_excavata_i_/2068809 <p>A carbazole-pyranocoumarin conjugate, carbazomarin B (<b>1</b>), and two carbazole alkaloids, 6-methoxymukonidine (<b>2</b>) and 2-hydroxy-3-methoxycarbazole <b>(3</b>), together with 27 known compounds (<b>4</b>–<b>30</b>), were isolated from the stems of <i>Clausena excavata</i>. Their structures have been elucidated by spectroscopic analyses. Compound <b>2</b> showed moderate cytotoxicity to HuCCA-1, MOLT-3 and HepG2 cancer cell lines with IC<sub>50</sub> values of 15.09–28.50 μg/mL, but none to A549 cell line. Heptaphylline (<b>6</b>) and nordentatin (<b>23</b>) were found to show moderate cytotoxic activity against HepG2 cell line with IC<sub>50</sub> values of 12.33 and 11.33, respectively, while clausine K (<b>27</b>) exhibited strong cytotoxicity with IC<sub>50</sub> value of 1.05 μg/mL, better than a standard drug (etoposide, IC<sub>50</sub> 13.40 μg/mL).</p>