Kazuko Yoshikawa*†, Takuya Ito†, Kanako Iseki†, Chihiro Baba†, Hiroshi Imagawa†, Yasuyuki Yagi†, Hiroshi Morita‡, Yoshinori Asakawa†, Sachiko Kawano§, and Toshihiro Hashimoto†
† Faculty of Pharmaceutical Sciences, Tokushima Bunri University, Yamashiro-cho, Tokushima, 770-8514, Japan
‡ Faculty of Pharmaceutical Sciences, Hoshi University, Ebara 2-4-41 Shinagawa, Tokyo 142-8501, Japan
§ Kawano Mericlone Co., Ltd., Hokushou 562-1, Wakimachi, Mima, Tokushima 779-3604, Japan
J. Nat. Prod., Article ASAP
DOI: 10.1021/np200788u
Publication Date (Web): March 9, 2012
A new phenanthrendione, ephemeranthoquinone B (1), two phenanthrenes, marylaurencinols A (2) and B (3), and a phenanthrene glucoside, marylaurencinoside A (4), were isolated from the roots of Cymbidium Great Flower Marie Laurencin, along with six known phenanthrenes, 5–10. The structures of these compounds were established by a combination of extensive NMR spectroscopy and/or X-ray crystallographic analysis and chemical degradation. The compounds were tested for antibacterial activities against Bacillus subtilis and Klebsiella pneumoniae and for cytotoxic activity against the human promyelocytic leukemia (HL-60) cell line. Compounds 1, 3, and 6 showed antibacterial activities with minimum inhibitory concentration (MIC) values in the range of 4.88 to 65.10 μM. Notably, ephemeranthoquinone B (1) had a strong antibacterial effect on B. subtilis. Furthermore, 1 exhibited moderate cytotoxic activity (IC50 2.8 μM) against HL-60 cells. Compounds 4–9 also showed weak cytotoxic activity against the HL-60 cell line with IC50 values of 19.3–52.4 μM.