title: Analysis and identification of lignans in Phyllanthus urinaria by HPLC-SPE-NMR.
abstract: HPLC-SPE-NMR has been applied to the analysis of a number of structurally similar lignans present in Phyllanthus urinaria. A reversed-phase HPLC system, using a C8 column eluted with tetrahydrofuran-water-methanol and detected at 225 nm was developed that gave good resolution for seven lignans from Phyllanthus urinaria. Coupling of this system with SPE-NMR provided clean 1H-NMR spectra for nine lignans present in 4 mg of a lignan-rich fraction, equivalent to ca. 1.0 g of dry plant material. The result demonstrates that HPLC-SPE-NMR is a very efficient and powerful tool for the unambiguous identification of natural products that have been previously characterised.
authors.affiliation: School of Pharmacy, College of Medicine, National Taiwan University, 1 Jen-Ai Rd., Sec. 1, Taipei 100, Taiwan, Republic of China.
authors.forename: Chen-Yu
authors.initials: CY
authors.lastname: Wang
authors.forename: Shoei-Sheng
authors.initials: SS
authors.lastname: Lee
mesh_terms: D002851:Chromatography, High Pressure Liquid; D017705:Lignans / Q000032:analysis* / Q000737:chemistry; D009682:Magnetic Resonance Spectroscopy; D015394:Molecular Structure; D029803:Phyllanthus / Q000737:chemistry*
chemical_list: D017705:Lignans