Potent inhibitors of histamine release: polyhydroxylated sterols from the Okinawan soft coral Sinularia abrupta

A new polyhydroxylated steroid (24-methylene-1 alpha, 3 beta, 11 alpha-trihydroxycholest-5-ene-18-oic acid-3-acetate, 1) and known related compounds (2-4) from the soft coral Sinularia abrupta have potently inhibited histamine release from rat peritoneal mast cells induced by anti-immunoglobulin E. The inhibitory effect of 1 was approximately 6500 times stronger than that of disodium cromoglycate, a well-known antiallergic drug.

New delta 8- and delta 8(14)-5 alpha,6 alpha-epoxysterols from the marine sponge Spongia officinalis

Six new delta 8- and delta 8(14)-5 alpha,6 alpha-epoxysterols (1-6) have been isolated from a collection of the Mediterranean sponge Spongia officinalis. The structures of the new metabolites, isolated as diacetate derivatives, have been determined by spectral analyses and an x-ray diffraction experiment performed on the diacetyl derivative of 1.

Production of a novel steroid sulfate metabolite [4,4,24-trimethylcholesta-8,14,24(28)-trien-2 alpha,3 beta,11 alpha,12 beta-tetrol 12-acetate, 3-sulfate] by Fusarium species and its biological activity

A novel steroid sulfate, 4,4,24-trimethylcholesta-8,14-24(28)-trien-2 alpha,3 beta,11 alpha,12 beta- tetrol 12-acetate, 3-sulfate, was discovered in Fusarium spp. Forty Fusarium strains belonging to F. sporotrichioides, F. chlamydosporum, E. equiseti, F. acuminatum, F. sambucinum, F. culmorum, and F. graminearum produced the steroid on white corn grits at 25 degrees C for 20 days. This steroid sulfate is one of the more abundant and easily attainable microbial steroids. At a concentration of 160 micrograms/ml, it inhibited the growth of six fungi, two gram-positive bacteria, and an alga, as well as the germination of both wheat and tomato seeds.

20-isosterols from the marine bivalve Macoma balthica

A fraction of 20-isosterols has been isolated from the Baltic Sea bivalve Macoma balthica. The main component of this fraction, (20S)-cholest-5-en-3 beta-ol, has been characterized by 300 MHz nuclear magnetic resonance spectroscopy. 20-Isosterols in M balthica probably originate from sea-bottom sediments, an important component of a diet of the animal studied.

Identification of 8 alpha,25-dihydroxy-9,10-seco-4,6,10(19)-cholestatrien-3-one as a product of metabolism of 25-hydroxycholecalciferol by liver microsomes

The ability of liver microsomes, sites of synthesis of 25-hydroxycholecalciferol, to further metabolize 25-hydroxycholecalciferol has been assessed. When liver microsomes were incubated with 25-hydroxycholecalciferol in the presence of cytosol, a metabolite was isolated that comigrated with 8 alpha,25-dihydroxy-9,10-seco-4,6,10(19)-cholestatrien-3- one in three different chromatographic systems. The ultraviolet spectrum (220-350 nm) and mass spectrum of the purified metabolite were identical to that of synthetic 8 alpha,25-dihydroxy-9,10-seco-4,6,10(19)-cholestatrien-3-one. This study indicates that liver microsomes convert 25-hydroxycholecalciferol to 8 alpha,25-dihydroxy-9,10-seco-4,6,10(19)-cholestatrien-3-one. The significance of this metabolite, which has been shown previously by others to be produced by alveolar macrophages, has yet to be determined.

Three new 7-keto sterols from the Mediterranean sponge Clathrina clathrus

The CHCl3 extract of the Mediterranean sponge Clathrina clathrus was shown to contain three new sterols: (22 E)-3 beta-hydroxycholesta-5,8,22-trien-7-one (1), (22 E, 24 xi)-3 beta-hydroxy-24-methylcholesta-5,8,22-trien-7-one (2), and (22 E, 24 xi)-3 beta-hydroxy-24-ethylcholesta-5,8,22-trien-7-one (3), whose structures were elucidated on the basis of physico-chemical evidence.

Isolation and structure of a cytotoxic epoxy sterol from the marine mollusc Planaxis sulcatus

A novel epoxy sterol isolated from the marine mollusc Planaxis sulcatus has been identified as 9 alpha,11 alpha-epoxycholest-7-ene-3 beta,5 alpha,6 beta-triol by spectrometric methods.

Inhibitors of sterol synthesis. Reverse phase high performance liquid chromatography for the separation of cholesterol, 5 alpha-cholest-8(14)-en-3 beta-ol-15-one, and their fatty acid esters

A relatively simple and rapid method was required for the separation of 5 alpha-cholest-8(14)-en-3 beta-ol-15-one, a potent inhibitor of sterol synthesis, from its major metabolites. Conditions have been determined which permit the resolution of the 15-ketosterol and cholesterol and fatty acid esters of the two sterols by reverse phase high performance chromatography. This methodology also permits the resolution of the major esters of the 15-ketosterol and of cholesterol.

Isolation, identification, and chemical synthesis of 8 alpha,25-dihydroxy-9,10-seco-4,6,10(19)-cholestatrien-3-one. A new metabolite of 25-hydroxyvitamin D3 produced by mouse myeloid leukemia cells (M1)

It is known that phagocytic cells such as monocyte-macrophages and myeloid leukemia cells metabolize 25-hydroxyvitamin D3 to 10-oxo-19-nor-25-hydroxyvitamin D3. Now we have found that phagocytic cells metabolize 25-hydroxyvitamin D3 not only to 10-oxo-19-nor-25-hydroxyvitamin D3 but also to a new metabolite eluted just after 24R,25-dihydroxyvitamin D3 on straight phase high pressure liquid chromatography with a 2-propanol-hexane solvent system. The new metabolite, produced by murine myeloid leukemia cells (M1), was isolated in pure form and identified as 8,25-dihydroxy-9,10-seco-4,6,10(19)-cholestatrien-3-one on the basis of mass, ultraviolet, infrared, and proton magnetic resonance spectra. The 8 alpha-hydroxy epimer of the putative metabolite was chemically synthesized in two steps starting from 25-hydroxyvitamin D3. The spectral data and chromatographic behavior of chemically synthesized 8 alpha,25-dihydroxy-9,10-seco-4,6,10(19)-cholestatrien-3-one coincided exactly with those of the isolated metabolite, indicating that the stereochemistry of the hydroxyl group at the 8-position is alpha. On the basis of the structural characteristics of the two metabolites produced from 25-hydroxyvitamin D3 (the present metabolite and 10-oxo-19-nor-25-hydroxyvitamin D3), it is suggested that dioxygenases are involved in the production of these metabolites from 25-hydroxyvitamin D3 in phagocytic cells.

Sterols of the cultured euglenid Eutreptia viridis: a novel delta 23-unsaturated sterol

The sterol mixture isolated from the marine alga Eutreptia viridis consists mainly of delta 5,7-dienes which account for 80% of the free sterols. Eighteen different sterols were detected, including a novel sterol with the rare delta 23-unsaturation, viz. 24-ethylcholesta-5,7,23Z-trien-3 beta-o1.

The ecdysteroids from young embryonated eggs of the tobacco hornworm

26-Hydroxyecdysone, which is the major free recoverable ecdysteroid of older age groups of embryonated eggs of the tobacco hornworm was also the major component in 4- to 18-hour-old embryonated eggs. The other 3 beta-ecdysteroids, ecdysone, 20-hydroxyecdysone, and 20,26-dihydroxy-ecdysone, were also present and accounted for all the molting hormone activity; 26-hydroxyecdysone was devoid of molting hormone activity in the house fly assay. 20-Hydroxyecdysone was a minor component, which confirms the earlier observations that the main metabolic route for ecdysteroids during embryonic development is that leading to 26-hydroxyecdysone, whereas formation of 20-hydroxyecdysone is a minor pathway. A new 3 alpha-ecdysteroid, 3-epi-26-hydroxyecdysone, also devoid of molting hormone activity, was the second major ecdysteroid isolated from the eggs. 3-Epi-20,26-dihydroxyecdysone was detected in very minute amounts. In addition to the six 3 beta-and 3 alpha-ecdysteroids there were at least an equivalent number of unknown ecdysteroids all of which lacked molting hormone activity. Their physical properties including chromatographic behavior are discussed.

Characterization of two steroidal ketones and two isoprenoid alcohols in dairy products

Two steroidal ketones, delta-4-cholesten-3-one and delta-3,-5-cholestadiene-7-one, were isolated and identified for the first time in anhydrous milk fat and in nonfat dry milk. Together with these, two isoprenoid alcohols, phytol and dihydrophytol, were identified in anhydrous milk fat. Their identities were established on the basis of chromatographic and mass spectral data and confirmed by comparison with authentic materials.

The isolation of cholest-5-ene-3beta,26-diol from human brain

Cholest-5-ene-3beta,26-diol, isolated from human brain, was further characterized by oxidation to 3-oxocholest-4-en-26-ol and to 3-oxocholest-4-en-26-oic acid. Identification was achieved by comparison (by t.l.c., g.l.c. and g.l.c.-mass spectrometry) with corresponding reference compounds derived from kryptogenin.