New Hyperforin Derivatives from Hypericum revolutum VAHL with Growth-Inhibitory Activity against a Human Colon Carcinoma Cell Line
✍ Scribed by Laurent A. Decosterd; Helen Stoeckli-Evans; Jean-Charles Chapuis; Jerome D. Msonthi; Bernard Sordat; Kurt Hostettmann
- Publisher
- John Wiley and Sons
- Year
- 1989
- Tongue
- German
- Weight
- 490 KB
- Volume
- 72
- Category
- Article
- ISSN
- 0018-019X
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✦ Synopsis
The crude petroleum-ether extract of the root bark of Hypericum revolutum VAHL (Guttiferae) exhibited in uitro growth-inhibitory activity against the Co-1 15 human colon carcinoma cell line. Activity-guided fractionation of this extract resulted in the isolation of two new hyperforin derivatives 1 and 2. The structure of 1 (hyperevolutin A) was established by X-ray analysis as the 4-hydroxy-8-exo -methyl-5,7-exo -bis(3-methylbut-2-enyl)-1 -@methyl-I -oxopropyl)-8-endo-(4-methylpent-3-enyl)bicyclo[3.3.l]non-3-ene-2,9-dione. The structure of the homologue 2 was deduced by comparison of its UV and 'H-and I3C-NMR spectra with those of 1.
Introduction. -The antibiotic properties of extracts of Hypericum species (Guttiferae) are well established [ 1-31. One active constituent, designated hyperforin, was isolated from Hypericumperforatum L. and first characterized in 1971 [4] [5]. A number of reports have appeared on this novel antibiotic, particularly on its controversial absolute configuration [&9], but finally X-ray analysis of its 3,s-dinitrobenzoate [lo] and p-bromobenzoate [ 113 allowed direct proof of its absolute configuration.
Recent phytochemical investigations of various Hypericum species for new bioactive products led to the isolation of saroaspidine A, B, and C from Hypericum japonicum THUNB. [12] and of chinesin 1 and 2 from Hypericum chinense L. [13]. All isolated compounds were shown to display interesting antimicrobial activities against various microorganisms. In addition, chinesin 1 had relatively strong activity in a cytotoxicity test against HeLa cells.
Finally, in the course of our systematic chemical and biological screening studies of African plants, antifungal chromenyl ketones have been isolated from the aerial parts of Hypericum revolutum VAHL [14]. Hypericum revolutum is a shrub native to South-East Africa, growing at altitude along the margins of evergreen forests. More extensive investigations showed that the petroleum-ether extract of the root bark of Hypericum revolutum displayed significant growth-inhibitory activity against the Co-1 15 human colon carcinoma cell line. Hyperevolutin A (1) and B (2) were shown to be the main active -')