Simultaneous Determination of Triptolide and Tripdiolide in Extract of Tripterygium wilfordii Hook. f. by LC–APCI-MS

A novel method using liquid chromatography coupled with atmospheric pressure chemical ionization mass spectrometry in the negative selected ion monitoring mode has been developed and validated for rapid simultaneous determination of triptolide and tripdiolide in the extract of Tripterygium wilfordii Hook. f. The molecular ions m/z [M–H]⁻ 359 and 375 were selected for the quantification in selected ion monitoring mode for triptolide and tripdiolide. Standard calibration curve was linear over the concentration range of 0.12–24 and 0.15–30 μg mL⁻¹ for triptolide and tripdiolide. The relative standard deviations of intra- and inter-day were in the range of 4.7–9.9 and 8.9–12.6%. The average recoveries were between 96.4 and 104.6%. The limits of quantitation were 2.0 × 10⁻³ and 2.5 × 10⁻³ μg mL⁻¹ for triptolide and tripdiolide.     

Two new terpenes from Tripterygium wilfordii

<正>Two new terpenes,wilfornine H(1) and triptobenzene Q(2) were isolated from Tripterygium wilfordii,as well as 11 terpenes. Their structures were elucidated by spectroscopic methods.Compounds 5,9-13 showed significant immunosuppressive activities.     

Two New Abietane Diterpenoids from the Roots of Tripterygium wilfordii Hook. f.

Two new abietane‐type diterpenoids, named triptobenzene R ( 1 ) and triptobenzene S ( 2 ), together with three known abietane‐type diterpenoids, triptophenolide ( 3 ), triptonodiol ( 4 ), and triptonoterpene methyl ether ( 5 ), were isolated from the roots of Tripterygium wilfordii Hook . f. Their structures and relative configurations were established by detailed spectral studies, including 1D‐ and 2D‐NMR (HSQC, HMBC, and NOESY), and HR‐ESI‐TOF‐MS, and by comparison with published data. Their absolute configurations were assigned by the CD technique, applied for the first time to abietane diterpenes from Tripterygium wilfordii. Compound 2 is the first abietane‐type norditerpenoid isolated from the genus Tripterygium.     

Ytterbium triflate hydrate catalyzed Michael addition and cyclocondensation of α,β-unsaturated ketones with active methylene compounds

Catalyzed by ytterbium（III） triflate hydrate [Yb（OTf）3.xH20], the Michael addition and cyclocondensation of α,β-unsaturated ketones with active methylene compounds to afford the 1,4-adducts and benzo[b]pyran derivatives, respectively were studied.     

A Novel Diterpenoid,11—O—β—D—glucopyranosylneo—triptophenolide, from Tripterygium wilfordii Hook.f

A new diterpenoid was isolated from the ethanolic extract of the dried root bark of Tripterygium wilfordii Hook.f. It is the first example of abietane diterpenoid glycoside isolated from Tripterygium wilfordii Hook.f.Its structure was identified to be 11-0-β-D-glucopyranosyl-neotriptophenolide based on spectral methods.     

Separation and simultaneous determination of seven bioactive components in Tripterygium wilfordii Hook. F. and Tripterygium preparations by micellar electrokinetic capillary chromatography

A simple, comprehensive, and highly selective MEKC method has been developed for simultaneous analysis of seven bioactive components (triptolide, wilfortrine, wilfordine, wilforgine, wilforine, triptophenolide, and triptonide) in the root extracts of Tripterygium wilfordii Hook. F. (TWHF) and Tripterygium preparations (TPs). Optimal BGE consisted of 10 mM sodium tetraborate, 30 mM SDS, and 30% v/v methanol. The separation voltage was 20 kV and the temperature was 25°C. A DAD was used and the detection wavelength was at 218 nm. Under the optimum conditions, the baseline separation of seven components was achieved in less than 26 min. Excellent precision, good stability, and accuracy were obtained. For all analytes, linear calibrations were established within 10–100 μg/mL. The LOD and LOQ were within 1.2–4.2 μg/mL and 4.0–14 μg/mL, respectively. The developed method was suitable for the determination of key components in TWHF and TPs.     

Simple method for determination of five terpenoids from different parts of Tripterygium wilfordii and its preparations by HPLC coupled with evaporative light scattering detection

By optimizing the extraction, separation, and analytical conditions, a reliable and accurate high-performance liquid chromatography method coupled with evaporative light scattering detection (ELSD) was developed for simultaneous determination of five terpenoids, i.e., triptolide, tripchlorolide, demethylzelastral, wilforlide B, and wilforlide A, in root, stem, leaves, root bark, twig, and root without bark of Tripterygium wilfordii Hook. f and six of its herbal preparations. This approach would thus provide a more accurate and general method for evaluating the quality of the herb and its preparations. Separation of these five terpenoids was achieved on a ZORBAX Eclipse XDB-C8 column with gradient elution using water and acetonitrile as solvents, both containing 0.05% formic acid, at a temperature of 30 degrees C and a flow rate of 0.8 mL/min. The drift tube temperature of ELSD was set at 100 degrees C, and the nitrogen flow rate at 1.5 L/min. Good linear relationships were obtained with correlation coefficients for the analytes exceeding 0.992, and the LOD and LOQ were less than 0.149 microg and 0.297 microg on column, respectively. Intra-day and inter-day precision of the analytes were less than 1.25% and 5.97%, respectively, and the average recovery rates obtained were in the range of 95.9 +/- 3.7% to 100.4 +/- 5.0% for all terpenoids with RSDs below 4.99%. Quantitative analysis of the five terpenoids in different parts of Tripterygium wilfordii and its six preparations showed that the contents of the terpenoids varied significantly. The tender root contained higher concentrations of triptolide, tripchlorolide, demethylzelastral, and wilforlide B than any other part of the herb. Correspondingly, the root bark contained the greatest concentration of wilforlide A, and the stem and twig came in second and third. This suggested that we could infer whether the medicinal materials were absolute roots without bark or not from the comparative contents of these terpenoids in the tablets in view of the fact that only the roots without bark are the valid officinal part of the plant. This method and the quantitation results obtained can provide a scientific and general as well as simple and convenient approach for the product manufacturers to set up quality control standards and for informing the public about the quality and safety of the preparations.     

Potential hypoglycemic effect of acetophenones from the root bark of Cynanchum wilfordii

Three new acetophenones, named cynwilforones A–C (1–3), together with cynandione A (4) were isolated from the root bark of Cynanchum wilfordii (Maxim.) Hemsl. Their structures were deduced based on spectroscopic analysis and chemical methods. Compounds 1 and 4 exhibited potential hypoglycemic effects through inhibition of hepatic gluconeogenesis by down-regulating the expression of phosphoenolpyruvate carboxykinase and glucose-6-phosphatase. This is the first report that acetophenones from the root bark of C. wilfordii possesses potential hypoglycemic activity in vitro.     

Three new sesquiterpene alkaloids from the root of Tripterygium wilfordii

<正>Three new sesquiterpene alkaloids,1-desacetylwilforgine(1),1-desacetylwilforine(2),and 9′-hydroxy-2-nicotinoylwilforine (3) were isolated from the roots of Tripterygium wilfordii Hook f.,along with six known alkaloids.Their structures were established on the basis of spectral analysis.     

雷公藤胃漂浮缓释胶囊的制备及体外释放度的考察

制备了雷公藤胃漂浮缓释胶囊,对其释放机制进行考察.建立HPLC法考察其体外释放度,以羟丙基甲基纤维素(HPMCK4M)为主要辅料,制备亲水凝胶型骨架胶囊,采用L9(34)正交试验筛选出胶囊的处方.所制备的胃漂浮缓释胶囊在12h内呈良好的零级释药特征;以正交试验设计的雷公藤胃漂浮缓释胶囊处方合理,体外释放性能良好.