从草药中分离和纯化天然存在的异构体仍然具有挑战性。高速逆流色谱(HSCCC)已用于分离天然产物。在这项研究中,开发了一种离线多维高速逆流色谱(multi-DHSCCC)策略,利用原位浓缩技术和在线存储循环洗脱技术,从植物PiperbetleL的氯仿分配样品中快速分离生物活性异构的新木脂素。在程序中,在由石油醚-乙酸乙酯-甲醇-水(7:5:12:3)组成的两相溶剂系统中,使用在线储存回收技术实施粗样品(105mg),首先简单地提供了新木素卡德瑞酮(1,5.3mg)及其差向异构体(-)-地udatinB(2,6.4mg)。然后,在石油醚-乙酸乙酯-甲醇-水(5:5:11,15)的另一个溶剂系统中,使用原位浓缩技术和在线储存回收技术对残留物fra进行二维HSCCC洗脱。因此,KadsureninI(3,0.6mg)及其区域异构体比比尼奥利坦C(4,5.0mg),连同剩余的分数frb和frc,已获得。第三,重新加载frc以允许HSCCC使用采用原位浓缩策略的前溶剂系统再循环洗脱,并产生一对差向异构体,(7R,8S,1\'S)-1\'-烯丙基-5-甲氧基-8-甲基-7-胡椒基-7,8,3,6-四氢-2-氧代苯并呋喃(5,10.2mg),和3-上-(-)-Burchullin(6,2.6mg)。最后,从P.betle的粗级分中分离出三对较少量且结构相似的异构体1-6,化合物2,4-6和化合物1的92.5%,3的91.0%的高HPLC纯度,而1和3在1HNMR中的纯度分别为89.9%和91.1%,分别。整个分离过程快速高效。化合物1、2、4和5对5种耐药金黄色葡萄球菌与FICI在0.156至0.375之间的组合显示出显著的协同活性。这种新型的离线多维HSCCC策略可以扩展到快速分离复杂天然产物的应用。
Separation and purification of naturally occurring isomers from herbs are still challenging. High-speed counter-current chromatography (HSCCC) has been applied to isolate natural products. In this study, an off-line multi-dimensional high-speed counter-current chromatography (multi-D HSCCC) strategy was developed utilizing the in situ concentration technique with online storage recycling elution to rapidly separate bioactive isomeric
neolignans from chloroform-partitioned samples of the plant Piper betle L. In the procedure, the crude sample (105 mg) was implemented using the online storage recycling technique in a two-phase solvent system composed of petroleum ether-ethyl acetate-methanol-water (7: 5: 12: 3), which first simply afforded a neolignane kadsurenone (1, 5.3 mg) and its epimer (-)-denudatin B (2, 6.4 mg). Then, the remains fr a was subjected to the second-dimensional HSCCC elution using the in situ concentration technique with online storage recycling technique in another solvent system of petroleum ether-ethyl acetate-methanol-water (5: 5: 11, 15). As a result, kadsurenin I (3, 0.6 mg) and its regioisomer pibeneolignan C (4, 5.0 mg), together with the fractional remaining fr b and fr c, were obtained. Thirdly, the fr c was reloaded to allow the HSCCC for recycling elution with the former solvent system employing the in situ concentration strategy and yielded a pair of epimers, (7R,8S,1\'S)-1\'-allyl-5-methoxy-8-methyl-7-piperonyl-7,8,3,6-tetrahydro-2-oxobenzofuran (5, 10.2 mg), and 3-epi-(-)-burchullin (6, 2.6 mg). Finally, the three pairs of less amount and the structurally similar isomers 1-6 were isolated from the crude fraction of P. betle with a high HPLC purity of over 95.0 % for compound 2, 4-6 and 92.5 % for compound 1, 91.0 % for 3, while the purity of 1 and 3 in 1H NMR were 89.9 % and 91.1 %, respectively. The whole isolation process was quick and efficient. Compounds 1, 2, 4 and 5 showed significantly synergistic activities combining several antibiotics against five drug-resistant Staphylococcus aureus with FICIs from 0.156 to 0.375. This novel off-line multi-dimensional HSCCC strategy could be broadened to application for the rapid separation of complex natural products.