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Phloroglucinol Derivatives (phloroglucinol + derivative)
Selected AbstractsPolyprenylated Phloroglucinol Derivatives from Hypericum sampsoniiHELVETICA CHIMICA ACTA, Issue 6 2003Yun-Lian Lin Six new prenylated phloroglucinol derivatives, hypersampsones A,F (1,6), were isolated from the aerial part of Hypericum sampsonii, together with 2,4,6-trihydroxybenzophenone, 2,4,6-trihydroxybenzophenone 4- O -geranyl ether, 2,4,6-trihydroxybenzophenone 3- C -geranyl ether, sampsoniones D and H. Their structures were elucidated by spectroscopic methods, mainly 1D- and 2D-NMR spectroscopy and mass spectrometry. [source] Hypericum caprifoliatum (Guttiferae) Cham.FUNDAMENTAL & CLINICAL PHARMACOLOGY, Issue 6 2006& Schltdl.: a species native to South Brazil with antidepressant-like activity Abstract In this work, previously published and unpublished results on biological activity of Hypericum caprifoliatum, a native specie to South Brazil, are presented. Lipophilic extracts obtained from this species showed an antidepressant-like activity in mice and rat forced swimming test. Results from in vivo experiments suggest an effect on the dopaminergic transmission. Besides that, in vitro experiments demonstrated that the extract and its main component (a phloroglucinol derivative) inhibit monoamine uptake in a concentration-dependent manner, more potently to dopamine, but this effect is not related to direct binding at the uptake sites. It was also observed that a 3-day treatment with lipophilic extract prevents stress-induced corticosterone rise in mice frontal cortex but not in plasma. The lipophilic and methanolic H. caprifoliatum extracts also demonstrated antinociceptive effect, which seems to be indirectly mediated by the opioid system. These results indicate that H. caprifoliatum presents a promising antidepressant-like effect in rodents which seems to be related to a mechanism different from that of other classes of antidepressants. [source] Polyprenylated Phloroglucinol Derivatives from Hypericum sampsoniiHELVETICA CHIMICA ACTA, Issue 6 2003Yun-Lian Lin Six new prenylated phloroglucinol derivatives, hypersampsones A,F (1,6), were isolated from the aerial part of Hypericum sampsonii, together with 2,4,6-trihydroxybenzophenone, 2,4,6-trihydroxybenzophenone 4- O -geranyl ether, 2,4,6-trihydroxybenzophenone 3- C -geranyl ether, sampsoniones D and H. Their structures were elucidated by spectroscopic methods, mainly 1D- and 2D-NMR spectroscopy and mass spectrometry. [source] Structural investigations of isomeric oxidised forms of hyperforin by HPLC-NMR and HPLC-MSnPHYTOCHEMICAL ANALYSIS, Issue 5 2003J.-L. Wolfender Abstract The prenylated phloroglucinol hyperforin, thought to be an essential component for the anti-depressant activity of St. John's Wort (Hypericum perforatum), is unstable. The facile oxidative degradation of hyperforin poses serious problems for standardisation, and may also dramatically affect the pharmacological activity of the extracts. Hyperforin was dissolved in hexane and stored at room temperature for 3 days and yielded various closely related degradation products which, although dif,cult to isolate on the preparative scale, have been analysed by on-,ow and stop-,ow HPLC-NMR and HPLC-MS/MS. From on-line spectroscopic data, and with the aid of complementary in-mixture standard NMR two-dimensional correlation experiments, the different oxidised forms of hyperforin were found to be phloroglucinol derivatives in which a hydroxy-dihydrofuran ring is formed involving the enol OH at C-7 or C-9 (tautomeric form) and the prenyl chain at C-8 of the core nucleus of hyperforin. The strategy followed for the on-line identi,cation of these constituents is discussed. Copyright © 2003 John Wiley & Sons, Ltd. [source] | ||||||||||