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Isoforrethins A-D, four ent-abietane diterpenoids from Isodon forrestii var. forrestii
Ling Chen1, Qian Yang1, Kun Hu2
1State Key Laboratory of Phytochemistry and Plant Resources in West China, Kunming Institute of Botany, Chinese Academy of Sciences, Yunnan Key Laboratory of Natural Medicinal Chemistry, Kunming 650201, People's Republic of China; University of Chinese Academy of Sciences, Beijing 100049, People's Republic of China.
Abstract:
Four new ent-abietane diterpenoids, isoforrethins A-D (1-4), were isolated from the aerial parts of Isodon forrestii var. forrestii by a variety of chromatographic techniques. Their structures were elucidated on the basis of spectroscopic data interpretation, single crystal X-ray diffraction, and quantum chemical calculation. All of these compounds were evaluated for their cytotoxicity against five human tumor cell lines (HL-60, SMMC-7721, A-549, MCF-7 and SW-480), and compound 4 showed significant inhibitory activities against SMMC-7721, A-549, MCF-7, and SW-480.
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