Bi-bicyclic and bi-tricyclic compounds from Dendrobium thyrsiflorum.
One bi-bicyclic and two bi-tricyclic derivatives of coumarin-benzofuran, phenanthrene-phenanthrene and phenanthrene-phenanthraquinone, along with seven known compounds, were isolated from stems of Dendrobium thyrsiflorum Rchb.f. (Orchidaceae). On the basis of chemical, NMR (1H, 13C, HMQC, HMBC and NOESY) and mass spectrometry data, their structures were elucidated as denthyrsin [3-(5',6'-dimethoxybenzofuran-2'-yl)-6,7-dimethoxy-2H-chromen-2-one; 1], denthyrsinol (4,5'-dimethoxy-[1,1']biphenanthrenyl-2,5,4',7'-tetraol; 2), and denthyrsinone (7,4',7'-trihydroxy-2,2',8'-trimethoxy-[5,1']biphenanthrenyl-1,4-dione; 3). Compounds 1-3 and denthyrsinin (1,5,7-trimethoxyphenanthrene-2,6-diol; 4) showed significant cytotoxic activities against Hela (13.5, 9.3, 9.9 and 2.7 microM, respectively), K-562 (0.45, 1.6, 6.0 and 2.3 microM, respectively) and MCF-7 (18.1, not tested, 3.5 and 4.8 microM, respectively) cell lines.
Zhang
Guang-Nong
GN
Department of Pharmacognosy, China Pharmaceutical University, Nanjing 210038, China.
Zhong
Ling-Yan
LY
Bligh
S W Annie
SW
Guo
Ying-Li
YL
Zhang
Chao-Feng
CF
Zhang
Mian
M
Wang
Zheng-Tao
ZT
Xu
Luo-Shan
LS
D000818:Animals; D000972:Antineoplastic Agents, Phytogenic / Q000737:chemistry / Q000494:pharmacology; D045744:Cell Line, Tumor; D031667:Dendrobium / Q000737:chemistry*; D006801:Humans; D006844:Hydrocarbons, Cyclic / Q000737:chemistry* / Q000494:pharmacology; D015394:Molecular Structure; D018547:Plant Stems / Q000737:chemistry
D000972:Antineoplastic Agents, Phytogenic; D006844:Hydrocarbons, Cyclic