Ergosta‐5,7,9(11), 22‐tetraen‐3β‐ol and its 24ξ‐Ethyl Homolog, Two New Marine Sterols from the Red Sea Sponge Biemna fortis
1979; Wiley; Volume: 62; Issue: 6 Linguagem: Inglês
10.1002/hlca.19790620633
ISSN1522-2675
AutoresClaude Delseth, Yoel Kashman, Carl Djerassi,
Tópico(s)Traditional and Medicinal Uses of Annonaceae
ResumoAbstract The steroidal components of a Red Sea sponge, Biemna fortis , were fractionated through reversed phase HPLC. and analyzed by a combination of physical methods, including high resolution GC./MS. and 360 MHz 1 H‐NMR. The sponge contains five conventional Δ 5 ‐sterols, 1a – c , 1e , 1g , which comprise about 25% of the mixture and 2,5% of gorgosterol (1h) , a sterol never found before in Porifera. Three Δ 5,7,22 ‐sterols were also present as major components in the mixture (∼70%): cholesta‐5,7,22‐trien‐3β‐ol (2a) , ergosta‐5,7,22‐trien‐3β‐ol (2c) and (24 R )‐ethylcholesta‐5,7,22‐trien‐3β‐ol (2e) whereas two new tetra‐unsaturated sterols were identified in minor amounts (2%): ergosta‐5,7,9(11),22‐tetraen‐3β‐ol (3c) and 24ξ‐ethylcholesta‐5,7,9 (11), 22‐tetraen‐3β‐ol ( 3e or 3f ). NMR. spectroscopy made possible the assignment of a 24 R configuration for all the C(24) substituted sterols isolated in sufficient amount from the mixture. The possible symbiotic, dietary or biosynthetic origins of these sterols are discussed.
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