The blood-brain barrier permeability of 20(S) and 20(R)-protopanaxatriol epimers and dammar-20(22)E,24-diene- 313,6α,12β-triol were investigated using the MDCK-pHaMDR cell monolayer model. The bidirectional pe...
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The blood-brain barrier permeability of 20(S) and 20(R)-protopanaxatriol epimers and dammar-20(22)E,24-diene- 313,6α,12β-triol were investigated using the MDCK-pHaMDR cell monolayer model. The bidirectional permeability tests were carried out, and the apparent permeability coefficients (Papp) were calculated. The two protopanaxatriol epimers showed good permeability with Papp values of-10^-5 cm/s, whereas dammar-20(22)E,24-diene-3β,6α, 12β-triol showed poor permeability with Papp of 〈1 × 10^-7 cm/s. The three compounds showed differences in intracellular accumulations due to their different structures. Inhibition of P-gp with verapamil showed that the transport mechanisms in MDCK-pHaMDR cell monolayer for compounds 1 and 2 epimers were not only simple passive diffusion but also involving an effiux way mediated by P-gp. These findings provided new basis for the further study of compounds 1 and 2 acting on the brain.
To facilitate the species identification and quality assessment of Chaihu (Bupleuri Radix), a simple and valid chromatographic fingerprint method was developed. The method uses high-performance liquid chromatography...
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To facilitate the species identification and quality assessment of Chaihu (Bupleuri Radix), a simple and valid chromatographic fingerprint method was developed. The method uses high-performance liquid chromatography coupled with evaporative light scattering detector (HPLC-ELSD) and the data analysis is assisted by professional analytical software recommended by the State Food and Drug Administration (SFDA). The results indicate that Nan Chaihu raw materials and Chaihu decoction pieces vary markedly in chemical quality, while Bei Chaihu raw materials are relatively more stable. Furthermore, it is obvious that Nan Chaihu is chemically very different from Bei Chaihu, suggesting that Nan Chaihu may not be suitable for medicinal use. In addition, the obvious differences between the chromatograms of decoction pieces and raw materials, especially the peaks between 30 and 40 rain and after 45 rain, indicate possible effects of the processing procedures on the chemicals. By analyzing the fingerprints of all samples, 12 main saponin-like fingerprint peaks, of which at least three are characteristic peaks of saikosaponins a, c, and d, are proposed to be considered for further characterization and quality evaluation of Chaihu.
Methyleugenol (1), one of the main bioactive constituents of the seeds of Myristicafragrans Houtt. (family: Myristicaceae), was incubated with rat hepatic microsomes from rats pretreated with sodium phenobarbital...
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Methyleugenol (1), one of the main bioactive constituents of the seeds of Myristicafragrans Houtt. (family: Myristicaceae), was incubated with rat hepatic microsomes from rats pretreated with sodium phenobarbital. Eight biotransformation products named (R)-l'-methoxymethyleugenol (2), 3-(3,4-dimethoxyphenyl)-l-methoxyprop-2-ene (3), cis-3,4-dimethoxycinnamyl acetate (4), trans-3,4-dimethoxycinnamyl acetate (5), (R)-I hydroxymethyleugenol (6), trans-3,4-dimethoxycinnamyl alcohol (7), cis-3,4-dimethoxycinnamyl alcohol (8), and (R)-3-(3,4-dimethoxyphenyl)-propane-l,2-diol (9) were obtained and their structures were elucidated by NMR and MS data analysis and by comparison with the previously reported data. The biotransformation of 1 may provide valuable information for the use of methyleugenol. The NMR data of compounds 4 and 6 were reported for the first time.
A series of E and Z-isomers of 3-(4'-substituted benzylidene)-indolin-2-one derivatives were synthesized and separated. Based on their 1H NMR characterization, an unusual counterintuitive deshielding phenomenon for...
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A series of E and Z-isomers of 3-(4'-substituted benzylidene)-indolin-2-one derivatives were synthesized and separated. Based on their 1H NMR characterization, an unusual counterintuitive deshielding phenomenon for the protons presenting in the shielding zone of phenyl ring was observed and analyzed for the first time.
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