红棕杜鹃(原变种)叶中一个新的杜鹃色烯杂萜及其抗凝血活性评价

A new Rhododenderon chromene meroterpenoid from leaves of Rhododendron rubiginosum Franch.var.rubiginosum and its anticoagulant activity

采用硅胶、MCI Gel、Sephadex LH-20、ODS等柱色谱,结合半制备液相色谱,从红棕杜鹃(原变种)叶乙醇提取物的石油醚部位分离纯化得到一对双键位置异构的杜鹃色烯杂萜化合物:isoconfluentin(1)和(+)-confluentin(2),其中化合物1为新化合物。运用现代波谱学方法(1D和2D NMR、UV、IR、MS等)对所分离得到的化合物进行了结构鉴定,而且采用色烷/色烯螺旋规则(chromane/chromene helicity rule)鉴定它们的绝对构型均为2 S构型。测定化合物1和2的体外凝血酶原时间,发现它们均具有有效的抗凝血作用。

Two Rhododenderon chromene meroterpenoids,isoconfluentin(1)and(+)-confluentin(2),were isolated from the petroleum ether extract of ethanol fraction of the leaves of Rhododendron rubiginosum Franch.var.rubiginosum by using various chromatographic methods,including MCI Gel,sephadex LH-20,ODS,silica gel and semi-preparative HPLC.Their planar structures were identified by spectrographic methods,such as NMR,UV,IR,MS,and the absolute configuration of C-2 of 1 and 2 was determined to be the S configuration by the chromane/chromene helicity rule.Compound 1 is a new compound,and compounds 1 and 2 showed effective anticoagulant effect via prothrombin time assays in vitro.