title: Two new alkaloids from Brachystemma calycinum and their inhibitory effects on lymphocyte proliferation.
abstract: Two new alkaloids, brachystemidines F (1) and G (2), were isolated from the roots of Brachystemma calycinum. Their structures were established on the basis of detailed spectroscopic analyses, including extensive NMR and HR-MS techniques. Compound 2, which exhibits an unusual N-hydroxydiazenyl (HO-N=N) moiety, is a potent immunosuppressive agent, as demonstrated by inhibition of mouse T- and B-lymphocyte proliferation, with IC50 values of 6.33 and 5.60 microg/ml, resp.
authors: State Key Laboratory of Phytochemistry and Plant Resources in West China, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, 650204, PR China.
authors: Qing
authors: Q
authors: Lu
authors: Li
authors: L
authors: Zhang
authors: Guo-Rong
authors: GR
authors: He
authors: Heng-Xing
authors: HX
authors: Liang
authors: Guan-Hua
authors: GH
authors: Du
authors: Yong-Xian
authors: YX
authors: Cheng
mesh_terms: D000470:Alkaloids / Q000737:chemistry* / Q000302:isolation & purification / Q000494:pharmacology*; D000818:Animals; D029748:Caryophyllaceae / Q000737:chemistry*; D049109:Cell Proliferation / Q000187:drug effects; D002478:Cells, Cultured; D008214:Lymphocytes / Q000166:cytology* / Q000187:drug effects*; D009682:Magnetic Resonance Spectroscopy; D051379:Mice; D008807:Mice, Inbred BALB C; D015394:Molecular Structure
chemical_list: D000470:Alkaloids