【摘 要】
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Hybeanones A and B (1 and 2),two highly oxygenated and rearranged polycyclic polyprenylated acylphloroglucinols (PPAPs),were isolated from the aerial parts of Hypericum beanii.Their structures comprising absolute configurations were elucidated by spectro-
【机 构】
：
Hubei Key Laboratory of Natural Medicinal Chemistry and Resource Evaluation,School of Pharmacy,Tongj
论文部分内容阅读
Hybeanones A and B (1 and 2),two highly oxygenated and rearranged polycyclic polyprenylated acylphloroglucinols (PPAPs),were isolated from the aerial parts of Hypericum beanii.Their structures comprising absolute configurations were elucidated by spectro-scopic analysis,single-crystal X-ray diffraction,and quantum chemical calculations.Compounds 1.and 2 are defined by a newly as-sembled cyclopentanone unit fused to a tricyclic γ-lactone unit via a ketone carbonyl.The breakage of C-1/C-2 linkage via ret-ro-Claisen reaction,attack from C-1 to C-19,and Baeyer-Villiger oxidation at C-1/C-23 bond were presumed to be the key steps in the assembly of 1 and 2.The isolates 1 and 2 showed potential acetylcholinesterase (AchE) inhibitory activities,with ICs0 values of 21.34± 1.48 and 18.79 ±2.36 μmol/L,respectively.
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