5α‐24‐Norcholestan‐3β‐ol and (24Z)‐Stigmasta‐5,7,24(28)‐trien‐3β‐ol, Two New Marine Sterols from the Pacific Sponges Terpios zeteki and Dysidea herbacea

Abstract

SummaryThe steroidal components of 2 marine sponges, Terpios zeteki (from Hawaii) and Dysidea herbacea (from Australia) were fractionated through a combination of chromatographic methods, including reversed phase HPLC., and were analyzed by a combination of physical methods, including high resolution GC.-MS. and 360 MHz 'H-NMR. T. zeteki contains 6 conventional 5a-stanols which comprise 91% of the sterol mixture, and traces (0.5%) of a new C26 sterol, 5a-24-norcholestan-3/3-01. Minor amounts of conventional d5-sterols (6.5%) and of a single d4-3-ketosteroid (1.5%) were also present. In contrast, the Australian sponge (D. herbacea) contains 3 d5,7-sterols which comprise 1.5% of the sterol mixture, and one new C29 sterol, (24 Z)-stigmasta-5,7,24 (28)-trien-38-01, as the major component (75%). In addition, minor amounts of conventional 5a-stanols (0.5%), d5-sterols (5%) and 5a-d7-sterols (18%) were present in this complex sterol mixture. The possible dietary or endosymbiotic origins of these sterols are discussed.

Lipids of an Upper Albian Limestone, Deep Sea Drilling Project Site 465, Section 465A-38-3

“…Certainly 23,24-dimethylcholesteroids are known only in marine organisms. The steroidal ketones also may reflect direct inputs from marine organisms; for example, sponges and dinoflagellates contain cholest-4-en-3-one (XLIa) (Delseth et al, 1979) and 4,23,24-trimethylcholest-22en-3-one (XLII) (Withers et al, 1978), respectively. Alternatively, these compounds may be diagenetic derivatives of sterols (Gaskell and Eglinton, 1975;Gagosian and Smith, 1979).…”

Terpioside from the Marine Sponge Terpios sp., the First Glycosphingolipid Having an L‐Fucofuranose Unit

“…In fact, only a few papers describing the chemistry of Terpios species from the Pacific have been published so far, and these include reports on the isolation of nakiterpiosin, nakiterpiosinone, [6] and terpiodiene [7] from the Okinawan sponge Terpios hoshinata and a norcholestanol [8] from the Hawaian sponge Terpios zeteki.…”

Recent progress in the marine sterol field

“…We have recently isolated a fifth member of this class, the completely reduced 5m-24-norcholestan-36-ol (2) (Ref. 5), along with an entire series of C27 to C 5m-stanols from the Hawaiian sponge Terpios zeketi. An early report (Ref.…”

“…12). Alternatively, if an intermediate carbonium ion (10) is invoked then the terminal carbon atoms on the side chain of the 27-nor-C27 sterols could arise either from C-28, C-25 and C-26 or from C-25, C-28 and C-29 of the original C29 ster9 (5). The final step in each case (6-'-9, 73, and 8÷1) would be the introduction of a t double bond by a reduction-dehydrogenation sequence (Ref.…”

“…(68) ' -cholestatrien-3-ol (2) from the sponge Callyspongia diffusa, whose principal steroidal constituent is isofucosterol (5 Unlike the interesting keto or dihydroxy low molecular weight steroids recently isolated from marine sources (Refs. 56, 57), the C1-C25 sterols possess all the structural requirements to be included under the classical definition with that class of structural membrane constituants referred to as sterols.…”