Synthesis of flavaspidic acid AB / 中国药科大学学报

@#Flavaspidic acid AB is a bicyclic phloroglucinol derivative with various biological activities in Dryopteris fragrans (L.) Schott. The structure of flavaspidic acid AB was analyzed by inverse synthesis techniques, and its synthesis was designed under the principle of association. Using phloroglucinol as raw material, the 2-methyl-4-butyrylphloroglucinol was synthesized by Vilsmeier-Haack reaction, reduction and acylation, and the flavaspidic acid fragment was synthesized by acylation, alkylation and deacylation, after which N, N-dimethylmethyleneammonium iodide was activated and the flavaspidic acid AB was obtained. The structures of intermediates and flavaspidic acid AB were confirmed by MS, 1H NMR and 13C NMR, and the yield of the target product reached 14.7%. Results indicate that the designed synthetic route of flavaspidic acid AB is simple and easy.

Isolation and antibacterial activities of phloroglucinol derivatives from Dryopteris crassirhizoma / 中草药

Objective To isolate the phloroglucinol derivatives in Dryopteris crassirhizoma and to discuss its antibacterial activity. Methods The phloroglucinol derivatives were isolated and purified by column chromatography on silica gel, Sephadex LH-20, semi preparative liquid phase, and recrystallization. Structures were proved by physicochemical properties and spectral methods (MS, 1H-NMR, 13C-NMR). The antibacterial activities against fungi and bacteria were tested by CLSI M38-A2 and M07-A9. Results 10 derivatives were obtained from ethanol extracts of D. crassirhizoma, and were identified as 1-butyrylphloroglucinol (1), 1-methyl-3-butyrylphloroglucinol (2), 2-acetyl-4-butyrylphloroglucinol (3), 1-methyl-3-acetyl-5-butyrylphloroglucinol (4), flavaspidic acid PB (5), norflavaspidic acid AB (6), flavaspidic acid AA (7), filixic acid ABA (8), flavaspidic acid AB (9), and filixic acid ABP (10). The antibacterial activity of compound 8 against Staphylococcus aureus (S. aureus) and Staphylococcus epidermidis (S. epidermidis) was similar to cefoxitin (positive control), and the MIC of compound 8 was 2.5 μg/mL. Conclusion Compounds 1-4, new compounds, are isolated from D. crassirhizoma. Compound 8 has both antibacterial activities against fungi and bacteria.