A new prenylated flavanone from the roots of Sophora flavescens
Introduction
The dry root of Sophora flavescens Ait. (Fabaceae) is a well-known Chinese herbal medicine used as a diuretic and for the treatment of acute dysentery, gastrointestinal hemorrhage, and eczema [1], [2]. It is known to contain a number of quinolizidine alkaloids [3] and a series of flavonoids [3], [4], [5], [6], [7], [8]. In this paper, we report the structural determination of a new prenylated flavanone 1 on the basis of spectroscopic analysis, including 2D NMR spectroscopic techniques.
Section snippets
Results and discussion
Compound 1 was obtained as an amorphous yellowish powder, m.p. 204–206°C. Its molecular formula C21H22O5 was deduced from HREIMS (Found 354.1471, calc. 354.1467). The IR spectrum of 1 showed strong absorptions at 3345 (OH), 1649 (α,β-unsaturated CO) and 1603 cm−1 (aromatic CC), and UV absorptions at 289 and 321 nm (sh) which suggested the presence of a flavanone skeleton [9]. It was clear from the 13C-NMR spectrum [signals at 44.6 ppm (C-3), 77.8 ppm (C-2) and 188.1 ppm (C-4)] that 1 was a
Plant materials
The roots of S. flavescens Ait. were collected in August 1998, Yangku in Kangwon Province, Korea and authenticated by Dr T.J. Kim of our Institute. A voucher specimen (SSK98002) was deposited in the herbarium of the Natural Products Research Institute, Seoul National University.
Extraction and isolation
The dry roots (3.65 kg) were extracted three times with MeOH at room temperature. The MeOH extract was evaporated to dryness, and the dry residue was partitioned in succession between H2O and CH2Cl2, and then EtOAc
Acknowledgements
This work was supported by the research fund from KOSEF (Project No. 98-0403-11-01-3). We thank Drs Y.H. Kim and J.-J. Seo (Korea Basic Science Institute) for measurements of HREIMS and NMR, respectively. SSK and JSK gratefully acknowledge the financial assistance of the Ministry of Education through BK21 project.
References (17)
- et al.
J Plant Physiol
(1987) - et al.
- et al.
- et al.
Arch Pharm Res
(1997) - et al.
Chem Pharm Bull
(1985) - et al.
Yakugaku Zasshi
(1985) - et al.
Shoyakugaku Zasshi
(1989)