Polycyclic polyprenylated acylphloroglucinols (PPAPs) are a structurally diverse group of natural products possessing neurotrophic and antiproliferative activities. PPAPs have been reported so far only from plants of the families Clusiaceae (Guttiferae) and Hypericaeae, and the majority has been isolated from the genus Hypericum [1-3]. In a systematic search for new PPAPs from Iranian Hypericum species we investigated H. scabrum. The species is commonly known in Persian as "Gol-e Raeei deihimi", and is used in traditional Iranian medicine for the treatment of wounds, gastric ulcers, and as an antiseptic, sedative, and antispasmodic drug. From the n-hexane extract of the aerial parts three (1-3) new polyprenylated acylphloroglucinol derivatives (1-3) and compound 4 were obtained. Isolation was achieved by a combination of column chromatography on silica gel, and preparative and semipreparative HPLC. The structures were established on the basis of extensive spectroscopic analysis, including 1D and 2D NMR, HRMS, and ECD for determination of absolute configurations. Compound 3 represents a new scaffold of PPAPs, and compound 4 possesses a new scaffold for natural products.
References
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