Enantioseparation and Absolute Configuration Determination of Angular-Type Pyranocoumarins from Peucedani Radix Using Enzymatic Hydrolysis and Chiral HPLC-MS/MS Analysis
作者:Yue-Lin Song、Qing-Wen Zhang、Ya-Ping Li、Ru Yan、Yi-Tao Wang
DOI:10.3390/molecules17044236
日期:——
Angular-type pyranocoumarins from Peucedani Radix (Chinese name: Qian-hu) have exhibited potential for use on treatment of cancer and pulmonary hypertension. Due to the existence of C-3′ and C-4′ chiral centers, compounds belonging to this chemical type commonly exist in enantiomers and/or diastereoisomers, which may elicit distinct activities during their interactions with the human body. In the present study, a new method, which combines enzymatic hydrolysis with chiral LC-MS/MS analysis, has been developed to determine the absolute configurations of these angular-type pyranocoumarins. Pyranocoumarins isolated from Qian-hu, their enantiomers, or metabolites were individually incubated with rat liver microsomes. As the common end product from enzymatic hydrolysis of all tested pyranocoumarins, cis-khellactone was collected and its absolute configuration was determined by comparison with (+)-cis-khellactone and (−)-cis-khellactone using chiral LC-MS/MS. The absolute configurations of all tested parent pyranocoumarins were determined by combination of LC-MS/MS, NMR and polarimetric analysis. The results revealed that the metabolite cis-khellactone retained the same absolute configurations of the stereogenic carbons as the respective parent compound. This method was proven to be rapid and sensitive and also has advantages in discriminating single enantiomers and mixtures of optical isomers with different ratios.
从前胡(中文名:前胡)中提取的角型吡喃香豆素具有治疗癌症和肺动脉高压的潜力。由于存在C-3′和C-4′手性中心,属于这种化学类型的化合物通常以对映异构体和/或非对映异构体的形式存在,它们在与人体相互作用时可能产生不同的活性。在本研究中,我们开发了一种新的方法,将酶水解与手性LC-MS/MS分析相结合,用于确定这些角型吡喃香豆素的绝对构型。从前胡中分离出的吡喃香豆素、其对映异构体或代谢产物分别与大鼠肝微粒体孵育。作为所有测试吡喃香豆素酶水解的常见最终产物,收集顺式-山柰内酯,并通过使用手性LC-MS/MS与(+)-顺式-山柰内酯和(-)-顺式-山柰内酯进行比较来确定其绝对构型。通过结合LC-MS/MS、NMR和偏振分析,确定所有测试的吡喃香豆素母体的绝对构型。结果表明,代谢产物顺式-山柰内酯保留了与各自母体化合物相同的立体碳绝对构型。该方法被证明是快速和灵敏的,并且在