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At least 19 recordsLinked to original sources

Initial steroid-free versus steroid-based maintenance therapy and steroid withdrawal after heart transplantation: two views of the steroid question.

To determine any benefit of maintenance steroids in a cyclosporine and azathioprine immunosuppressive regimen, 112 heart transplant recipients were prospectively randomized to receive cyclosporine, azathioprine, and prednisolone (n = 59) or cyclosporine and azathioprine (n = 53). Of the 53 double-therapy patients, 47% were converted to maintenance steroids for resistant rejection or renal dysfunction. In a comparison of true double-therapy (n = 28) versus true triple-therapy (n = 59) groups, actuarial survival and systolic function did not differ. Linearized rejection during the first 3 months was lower with triple therapy than with double therapy (1.5 +/- 0.18 vs 2.3 +/- 0.23 episodes/100 patient-days; p less than 0.01) as were requirements for cytolytic therapy for rejection with hemodynamic compromise. Patients receiving triple therapy had significantly higher serum cholesterol levels and antihypertensive agent requirements at all annual time points up to 5 years. The rate of steroid-related morbidity (diabetes, bone complications, cataracts, and obesity) was low in both groups and did not differ significantly. Of the 204 patients receiving triple therapy at this unit, 45 underwent steroid withdrawal. The initial success rate was 69%, and an additional 14% of those who initially failed succeeded on the second attempt. Any rejection after steroid cessation tended to occur within 6 weeks. There were, however, no substantial short-term benefits in body weight or lipid or blood pressure control. In patients in whom infection or growth retardation was an indication for steroid withdrawal, these generally improved after cessation. Until predictive markers for the likely success of steroid withdrawal are identified, the case for steroid withdrawal, as opposed to steroid minimization, does not seem compelling.

Adult↗

[Usefulness of inhaled steroids in steroid-dependent intractable asthma--equivalent dose of oral steroid to inhaled steroid].

Twenty-four steroid-dependent intractable asthmatics were treated with oral prednisolone (PSL) (basic dose) + additional PSL and oral PSL (basic dose) + inhaled beclomethasone (BDP) alternately, to assess the clinical symptoms in each administration period. Equivalent doses of PSL to BDP were calculated. 1. Peak expiratory flow rate (PEF) during additional administration of BDP was markedly higher both in the morning and at night compared with that during additional administration of BDP was markedly higher both in the morning and at night compared with that during additional administration of PSL (p < 0.01 and p < 0.05 respectively). 2. The relation between additional doses of either PSL or BDP and attack scores was analysed in regression to obtain a dose equivalence line. 3. BDP 400 micrograms was equivalent to PSL 7.04 mg on average. 4. The equivalent dose of PSL to BDP tended to be lower in cases where the period of dependency on oral steroids was longer, the basic dose was larger, or the asthma was more severe. These data indicate that the application of inhaled steroids may be useful in the therapeutic management of steroid-dependent intractable asthmatics.

Administration, Inhalation↗

Spironolactone versus placebo or in combination with steroids for hirsutism and/or acne.

BACKGROUND: Hirsutism is the presence of excessive hair growth in women and is an important cosmetic condition often resulting in severe distress. Hirsutism is most often caused by increased production of male sex hormones also known as androgens. It is also affected by increased sensitivity to androgens in the hair follicles, and the secretory glands around the hair follicles, called sebaceous glands. Spironolactone is an antiandrogen and aldosterone antagonist used to treat hirsutism. Since 1978, many studies have been conducted to determine its effectiveness. OBJECTIVES: The objective of this review was to investigate the effectiveness of spironolactone and/or in combination with steroids (oral contraceptive pill included) in reducing excess hair growth and/or acne in women. SEARCH STRATEGY: All publications of randomised controlled trials of spironolactone versus placebo and/or in combination with steroids (oral contraceptive pill included) were identified. Search strategy was developed by the Menstrual Disorder Group. All accessable electronic databases were searched. In addition, all reference lists of relevant trials were searched and drug companies contacted for details of unpublished trials. SELECTION CRITERIA: All randomised controlled comparisons of spironolactone versus: placebo steroids (oral contraceptive pill included)) spironolactone of varying dosages or spironolactone and steroids versus steroids alone when used to reduce hair growth and acne in women. DATA COLLECTION AND ANALYSIS: Four trials were included in the review, seven trials were excluded. Two other trials are awaiting assessment. All included trials were small (no more than 31 participants) randomised and controlled. Only one trial studied acne as an outcome, the remaining three were concerned with hirsutism. One trial investigated spironolactone versus placebo; one trial was a dosage studies of spironolactone; one trial compared spironolactone with spironolactone in combination with dexamethasone; the remaining trial used topical spironolactone for the treatment of acne. Major outcome measures include the following: - subjective observations - Ferriman and Gallwey hair scores - hormonal and biochemical parameters - side effects - sebum production measurement MAIN RESULTS: All sample populations were small and confidence intervals were wide. There was no significant difference between treatments for any of the observed outcomes. REVIEWER'S CONCLUSIONS: The effectiveness of treatment for either acne vulgaris or hirsutism cannot be determined due to the small sample populations involved in the trials. Its value in clinical practice is difficult to assess from currently available research.

Acne Vulgaris↗

e-NO peak versus e-NO plateau values in evaluating e-NO production in steroid-naive and in steroid-treated asthmatic children and in detecting response to inhaled steroid treatment.

SUMMARY. Airway nitric oxide (NO) production can be measured by chemiluminescence analyzer in children able to perform a single low exhalation. The aim of the present study was to evaluate whether exhaled NO (e-NO) peaks (first part of the exhalation) were as useful as e-NO plateaus (last part of the exhalation) in evaluating e-NO production in asthmatic children and in detecting responses to inhaled steroid treatment. E-NO peak, plateau, and rate of production values were measured in 100 atopic asthmatic children using a chemiluminescence analyser. Thirty-seven patients (mean age, 11.1 +/- 0.7 years) were receiving inhaled steroids (flunisolide, 0.8-1 mg daily) or beclomethasone (0.2-0.4 mg daily), while the remaining 63 (mean age, 12.0 +/- 0.4 yrs) were-steroid naive and treated only with inhaled beta(2)-agonists on an as-needed basis. Fifteen out of the 63 steroid-naive patients were reevaluated after a short course (3 weeks) of inhaled corticosteroid treatment (flunisolide, 0.8-1 mg daily, or beclomethasone, 0.2-0.4 mg daily). Regardless of the type of data analysis (peak, plateau, or rate of production), the e-NO values of the steroid-naive patients were significantly higher than those of inhaled steroid-treated patients (P < 0.01, each comparison). Similarly, in the subgroup of steroid-naive patients, the three methods were able to detect a decrease in e-NO levels by inhaled steroid therapy (P < 0.001, each comparison). Plotting the difference between e-NO peak and e-NO plateau values against their average, the peak e-NO concentrations were higher than e-NO plateau values. This difference was independent of the absolute e-NO concentration. The results of the two types of data analysis seems to agree more closely in steroid-naive patients than in steroid treated patients, or in the subgroup of steroid-naive patients who received a short course treatment with inhaled steroids. In steroid-treated subjects, the differences were up to five times higher for peak than plateau e-NO values. These data suggest that both e-NO plateau and e-NO peak values are useful in detecting airway NO production in atopic asthmatic children, but they cannot be used interchangeably. Because of possible nasal contamination in e-NO peak measurement, we prefer e-NO plateau levels for evaluating lower airway e-NO production.

Administration, Inhalation↗

Homologous sequences in steroidogenic enzymes, steroid receptors and a steroid binding protein suggest a consensus steroid-binding sequence.

The amino acid sequences of two steroidogenic enzymes, P450c17 (steroid 17 alpha-hydroxylase/17,20 lyse) and P450c21 (steroid 21-hydroxylase), are only 28.9% identical. However, these proteins share a region of 21 amino acids bearing 17 identical residues, which we previously suggested may represent the steroid binding site. We assembled a sequence database of known steroid-binding proteins and searched this with the sequence of this 21 amino acid region. The steroidogenic enzymes, P450c17, P450c21, P450scc (the cholesterol side-chain cleavage enzyme), and P450c11 (steroid 11 beta/18-hydroxylase) share a subregion of 17 amino acids having at least 15 identical residues. Related sequences were identified in a computerized search of the available sequences of steroid hormone receptors and binding proteins. These sequences were invariably found within larger domains previously associated with steroid binding. From these we propose a more general consensus sequence of LPLLL +/- 000KDRE0LKRL +/- PV, where +/- refers to any charged amino acid, and 0 refers to an uncharged amino acid. This consensus sequence predicts 147 or 187 total amino acids in 11 human proteins examined (78.6%). An equivalent degree of sequence identity, 178 of 221 amino acids (80.5%) was found among 13 animal homologs of these human proteins. The ability of this consensus sequence to predict 325 of 408 amino acids (79.7%) strongly suggests this sequence is necessary, if not sufficient, for a steroid binding site in many proteins. Lecithin-cholesterol acetyl transferase, cholesterol ester transfer protein, and steroid sulfatase did not have sequences similar to our consensus sequence.

Amino Acid Sequence↗

Endogenous steroid metabolism is indicated by fluctuations of endogenous steroid and steroid glucuronide levels in early development of the steelhead trout (Oncorhynchus mykiss).

Concentrations of endogenous steroids and their glucuronide conjugates fluctuated during early development in steelhead trout Oncorhynchus mykiss. Whole body content of sex steroids and steroid glucuronides of both bisexual and gynogenetic (all female) steelhead trout were quantified by radioimmunoassay. Concentrations of 17beta-estradiol (E2) and cortisol increased 2-4 days before hatch. Two days after hatch, 11-ketotestosterone (11KT) increased in concentrations in both gynogenetic and bisexual populations, and 11KT glucuronide concentrations increased in the gynogenetic population. Testosterone (T) and E2 concentrations were at their lowest at 39 days postfertilization (dpf) for T and 39 and 61 dpf for E2. Changes in levels of steroid glucuronides were not consistently parallel to free steroids through time. T-, E2-, and 17alpha, 20beta dihydroxyprogesterone glucuronides declined slower than their free forms. Based on fluctuating concentrations of all steroid glucuronides, both populations of fish demonstrated an ability to form glucuronide conjugates of all steroids at the embryonic stage. The changes in levels of both free steroids and their glucuronides during early development of the trout indicate that steroid metabolism is active during development. This study also implicates steroid metabolism as an integral part of embryonic and postembryonic development.

Algestone↗

[Examination on aspirin-induced asthma and hypersensitivity to steroids--a questionnaire to 850 asthma on hypersensitivity to non-steroidal anti-inflammatory drugs and hypersensitivity to steroids].

We surveyed 850 patients with bronchial asthma and investigated such clinical features as the frequency of aspirin-induced asthma and hypersensitivity to steroids in the 457 available answers. We divided them into two groups, one was ASN: the asthmatics who had history of hypersensitivity to non-steroidal anti-inflammatory drugs, another was non-ASN: the asthmatics who had no history of hypersensitivity to non-steroidal anti-inflammatory drugs, and compared the two groups. The survey showed that the frequency of ASN was 12.0%. Its frequency rose with the severity of asthma to a level of 29.0% in severe cases. In ASN it was more frequent rates of female, infectious type, severe cases, and ASN had more frequent histories of oral use of steroids, use of ambulance, treatment in emergency rooms, and hospitalization than non-ASN. The serum IgE level was lower in ASN. The patients were 6 in ASN, none in non-ASN who had histories of hypersensitivity to steroids. They were 1.3% in all patients. 5 of 6 had past asthma attack progressived severely by rapid injection of succinate ester steroids and 2 of 6 had past by rapid injection of phosphoric acid ester steroids. In conclusion it was considered that we had to avoid rapid injection of steroids to aspirin-induced asthma and severe cases who were doubtful of aspirin-induced asthma in case of treatment of asthma attack.

Adult↗

Comparison of high dose inhaled steroids, low dose inhaled steroids plus low dose theophylline, and low dose inhaled steroids alone in chronic asthma in general practice.

BACKGROUND: Theophylline is widely used in the treatment of asthma, and there is evidence that theophylline has anti-inflammatory or immunomodulatory effects. A study was undertaken to determine whether theophylline added to low dose inhaled steroids would be as efficacious as high dose inhaled steroids in asthma. METHODS: In a study in general practice of 155 recruited asthmatic patients with continuing symptomatic asthma while on 400 microgram beclomethasone dipropionate (BDP) daily and inhaled beta(2) agonist as required, the effect of (1) continuing low dose inhaled steroids alone (LDS, 200 microgram BDP twice daily), (2) low dose inhaled steroids plus low dose theophylline (LDT, 400 mg daily), or (3) high dose inhaled steroids (HDS, 500 microgram BDP) over a six month period was examined. RESULTS: One hundred and thirty patients completed the study. Between group comparison using analysis of variance showed no overall differences in peak flow measurements, diurnal variation, and symptom scores. Changes in evening peak flows approached significance at the 5% level (p=0.077). The mean improvement in evening peak flow in the LDT compared with the LDS group was 20.6 l/min (95% confidence interval (CI) -2.5 to 38.8). In the LDT group there was an increase in evening peak flows at the end of the study compared with entry values (22.5 l/min), while in the LDS and HDS groups evening peak flows increased by 1.9 and 8.3 l/min, respectively. There was no significant difference in exacerbations or in side effects. CONCLUSION: There were no overall significant differences between the low dose steroid, low dose steroid with theophylline, and the high dose steroid groups. The greatest within-group improvement in evening peak flows was found after theophylline. A larger study may be necessary to show significant effects.

Adolescent↗

High-performance chromatofocusing of steroid receptor proteins in the presence and absence of steroid. Investigation of steroid-dependent alterations in surface charge heterogeneity.

We have previously reported the development of high-performance chromatofocusing (HPCF) systems for rapid evaluation of the surface charge heterogeneity of steroid receptor proteins, each in the presence of its specific steroid ligand. However, the surface charge properties of ligand-free receptor proteins remain largely unknown. We have now employed HPCF to rapidly evaluate the surface charge properties of cytosolic estrogen receptor proteins in both the presence and absence of the ligand ([3H]estradiol-17 beta). All operations were performed at 0-4 degrees C. Cytosols prepared from immature calf uteri were preparatively analyzed by HPCF on a SynChropak AX-500 column (25 cm X 4.6 mm I.D.) either before or after incubation with 5-10 nM [3H]estradiol-17 beta. Elution of receptor was by generation of internal pH gradients (pH 8.1 to 3.2) using Pharmacia Polybuffers 96 and 74. Postcolumn detection of previously unliganded receptor was accomplished by incubation of pH-neutralized (pH 7.4) fractions with 5 nM [3H]estradiol-17 beta in the presence and absence of unlabelled competitor. Specifically bound steroid was determined in each fraction using an hydroxylapatite adsorption assay. Significant surface charge heterogeneity was observed for both unliganded receptor and the steroid-receptor complex. The heterodisperse pattern of receptor surface charge appeared to vary in a steroid-dependent manner. Preformed steroid-receptor complexes eluted primarily between pH 6.5-7 and between pH 5-6, with indications for heterogeneity within both regions. The surface charge distribution of unliganded receptor routinely revealed additional, more acidic eluting (pH 3.8-4.6) receptor forms. Sodium molybdate, a commonly used receptor-stabilizing agent, maintains receptors during HPCF as relatively acidic eluting forms (pH 3.8-5.0). The specific elution profile of molybdate-stabilized receptor also appears steroid-dependent. These data demonstrate that HPCF can be used preparatively to rapidly isolate unliganded receptor forms in a biologically active state.

Adsorption↗

3 Beta-hydroxy-delta 5-steroid dehydrogenase/3-keto-delta 5-steroid isomerase from bovine adrenals: mechanism of inhibition by 3-oxo-4-aza steroids and kinetic mechanism of the dehydrogenase.

Several 3-oxo-4-aza steroids (1) have been identified as inhibitors of the 3 beta-hydroxy-delta 5-steroid dehydrogenase/3-keto-delta 5-steroid isomerase catalyzed conversion of pregnenolone to progesterone. By kinetically decoupling the two enzyme activities isolated from bovine adrenal cortex, it has been demonstrated that inhibition by 1 occurs through interference of both activities. A preferred ordered association of substrates to the 3 beta-hydroxy-delta 5-steroid dehydrogenase in which the cofactor binds prior to steroid was determined by isotope exchange at equilibrium. With this result, the dead-end inhibition patterns of 1 with the dehydrogenase were interpreted to originate from a preferred association of inhibitor within an enzyme ternate containing NADH; this proposal is supported by data from multiple inhibition analysis indicating synergistic binding of NADH and 1. Similarly, inhibition of the 3-keto-delta 5-steroid isomerase by the 3-oxo-4-aza steroids was enhanced in the presence of the positive effector NADH. On the basis of pH profiles upon Vm, Vm/Km, and 1/Ki for both enzyme activities, inhibition is proposed to result from the structural similarity of 1 to intermediate states formed upon enzyme catalysis.

3-Hydroxysteroid Dehydrogenases↗

Human placental 3 beta-hydroxy-5-ene-steroid dehydrogenase and steroid 5----4-ene-isomerase: purification from microsomes, substrate kinetics, and inhibition by product steroids.

In human pregnancy, placental 3 beta-hydroxy-5-ene-steroid dehydrogenase and steroid 5----4-ene-isomerase produce progesterone from pregnenolone and metabolize fetal dehydroepiandrosterone sulfate to androstenedione, an estrogen precursor. The enzyme complex was solubilized from human placental microsomes using the anionic detergent, sodium cholate. Purification (500-fold, 3.9% yield) was achieved by ion exchange chromatography (Fractogel-TSK DEAE 650-S) followed by hydroxylapatite chromatography (Bio-Gel HT). The purified enzyme was detected as a single protein band in sodium dodecylsulfate-polyacrylamide gel electrophoresis (monomeric Mr = 19,000). Fractionation by gel filtration chromatography at constant specific enzyme activity supported enzyme homogeneity and determined the molecular mass (Mr = 76,000). The dehydrogenase and isomerase activities copurified. Kinetic constants were determined at pH 7.4, 37 degrees C for the oxidation of pregnenolone (Km = 1.9 microM, Vmax = 32.6 nmol/min/mg) and dehydroepiandrosterone (Km = 2.8 microM, Vmax = 32.0 nmol/min/mg) and for the isomerization of 5-pregnene-3,20-dione (Km = 9.7 microM, Vmax = 618.3 nmol/min/mg) and 5-androstene-3,17-dione (Km = 23.7 microM, Vmax = 625.7 nmol/min/mg). Mixed substrate analyses showed that the dehydrogenase and isomerase reactions use the appropriate pregnene and androstene steroids as alternative, competitive substrates. Dixon analyses demonstrated competitive inhibition of the oxidation of pregnenolone and dehydroepiandrosterone by both product steroids, progesterone and androstenedione. The enzyme has a 3-fold higher affinity for androstenedione than for progesterone as an inhibitor of dehydrogenase activity. Based on these competitive patterns of substrate utilization and product inhibition, the pregnene and androstene activities of 3 beta-hydroxy-5-ene-steroid dehydrogenase and steroid 5----4-ene-isomerase may be expressed at a single catalytic site on one protein in human placenta.

3-Hydroxysteroid Dehydrogenases↗

Steroid sulphatase deficiency is the major cause of extremely low oestriol production at mid-pregnancy: a urinary steroid assay for the discrimination of steroid sulphatase deficiency from other causes.

A method for determining whether a pregnant woman with an extremely low serum oestriol (ELSE) measurement of mid-trimester is carrying a fetus with steroid sulphatase deficiency or another more serious disorder is described. We undertook GC/MS analysis of steroids in random maternal urine samples and quantified oestriol, oestriol precursors (dehydroepiandrosterone (DHEA), 5-androstene-3 beta, 17 beta-diol, 16 alpha-hydroxy-dehydroepiandrosterone and 5-androstene-3 beta, 16 alpha, 17 beta-triol), pregnanediol, and five other steroids largely unaffected by pregnancy (androsterone, etiocholanolone, tetrahydrocortisol, 5 alpha-tetrahydrocortisol and tetrahydrocortisone). Thirty-two samples collected from seven normal pregnant women between the 7th and 27th week of pregnancy and 22 from individuals with ELSE were analysed. Diagnostic ratios of excreted products were developed. These included ratios of oestriol and oestriol precursors to the cumulative value for the five non-pregnancy-related steroids and ratios of oestriol and oestriol precursors to pregnanediol and to each other. Our data demonstrated high 3 beta-hydroxy-5-ene steroid excretion in all ELSE patients together with low urinary oestriol excretion, a situation only consistent with deficiency of steroid sulphatase. The normal individuals had high oestriol and low excretion of oestriol precursors. No patient in our series showed the low oestriol levels and low oestriol precursor values that would indicate a fetal adrenal abnormality as the underlying defect.

Androstenediol↗

Mass spectrometry of steroid glucuronide conjugates. II-Electron impact fragmentation of 3-keto-4-en- and 3-keto-5alpha-steroid-17-O-beta glucuronides and 5alpha-steroid-3alpha,17beta-diol 3- and 17-glucuronides.

The steroid glucuronide conjugates of 16,16,17-d(3)-testosterone, epitestosterone, nandrolone (19-nortestosterone), 16,16,17-d(3)-nortestosterone, methyltestosterone, metenolone, mesterolone, 5alpha-androstane-3alpha,17beta-diol, 2,2,3,4,4-d(5)-5alpha-androstane-3alpha,17beta-diol, 19-nor-5alpha-androstane-3alpha,17beta-diol, 2,2,4,4-d(4)-19-nor-5alpha-androstane-3alpha,17beta-diol and 1alpha-methyl-5alpha-androstane-3alpha/beta,17beta-diol were synthesized by means of the Koenigs-Knorr reaction. Selective 3- or 17-O-conjugation of bis-hydroxylated steroids was performed either by glucuronidation of the corresponding steroid ketole and subsequent reduction of the keto group or via a four-step synthesis starting from a mono-hydroxylated steroid including (a) protection of the hydroxy group, (b) reduction of the keto group, (c) conjugation reaction and (d) removal of protecting groups. The mass spectra and fragmentation patterns of all glucuronide conjugates were compared with those of the commercially available testosterone glucuronide and their characterization was performed by gas chromatography/mass spectrometry and nuclear magnetic resonance spectroscopy. For mass spectrometry the substances were derivatized to methyl esters followed by trimethylsilylation of hydroxy groups and to pertrimethylsilylated products using labelled and unlabelled trimethylsilylating agents. The resulting electron ionization mass spectra obtained by GC/MS quadrupole and ion trap instruments, full scan and selected reaction monitoring experiments are discussed, common and individual fragment ions are described and their origins are proposed.

Deuterium↗

Steroids and hematopoiesis. II. The effect of steroids on in vitro erythroid colony growth: evidence for different target cells for different classes of steroids.

Androgenic steroids and their non-androgenic 5beta-H metabolites enhance the number of colonies of hemoglobin synthesizing cells grown from rat bone marrow in response to a standard (0.25 unit/ml) concentration of erythropoietin. The target cells for two steroids were found to be different. Cells influenced by the androgen, fluoxymesterone (fluoxy), resembled cells responding to erythropoietin in their cycle characteristics, as measured by tritiated thymidine suicide, and in their physical characteristics, as determined by velocity sedimentation gradient separation. Cells responding to etiocholanolone (etio) had a much lower tritiated thymidine suicide rate and different sedimentation velocities. Preincubation of marrow cells with etio for two hours was sufficient to enhance erythroid colony growth by 84%, whereas a similar incubation with fluoxy produced no increment. These studies demonstrate that different classes of steroids may influence in vitro erythropoiesis by acting on distinct populations of marrow cells. Fluoxymesterone appears to act through cells already committed to respond to erythropoietin, while etiocholanolone appears to act on a separate, perhaps more primitive population of marrow cells.

Animals↗

Steroidal 5-en-3-ones, intermediates of the transformation of steroidal 5-en-3 beta-ols to steroidal 4-en-3,6-diones oxidized by pyridinium dichromate and pyridinium chlorochromate.

Oxidation of cholesterol (1a) or pregnenolone (1b) with pyridinium dichromate (PDC) in dimethylformamide (DMF) or in dichloromethane (DCM) and pyridinium chlorochromate (PCC) in DCM provided cholest-4-en-3,6-dione (2a) or pregn-4-en-3,6,20-trione (2b). TLC monitoration of the reactions implied that cholest-5-en-3-one (3a) or pregn-5-en-3,20-dione (3b) and cholest-4-en-3-one (4a) or pregn-4-en-3,20-dione (4b) might be intermediates. Individual oxidation of 3a or 3b with PDC and PCC could give 2a or 2b, but 4a or 4b remained unchanged. Further investigation indicated that 4a or 4b was an isomerization product of 3a or 3b on silica gel TLC plate rather than really existence in the reaction mixture. These results shown steroidal 5-en-3-ones were intermediates of the transformation of steroidal 5-en-3 beta-ols to steroidal 4-en-3,6-diones oxidized by PDC and PCC.

Cholestenones↗

Steroids in Porifera. II. Steroid derivatives from two sponges of the family Halichondriidae. Sokotrasterol sulfate, a marine steroid with a new pattern of side chain alkylation.

A trisulfated derivative of 24,25,26,26-tetramethyl-5 alpha-cholest-23E-ene-2 alpha, 3 beta, 6 alpha-triol (sokotrasterol sulfate) has been isolated from the sponge Halichondriidae gen. sp., collected near Sokotra Island (Arabian Sea), and its structure has been elucidated. The side chain of the new steroid involves a "normal" alkylation at C-24 and the unprecedented addition of two extra methyl groups at C-26 and one extra methyl group at C-25. A free sterol fraction contained only 24-isopropyl-5-cholesten-3 beta-ol and 24-isopropyl-5, 22E-cholestadien-3 beta-ol. 24-Isopropyl-5, 22E-cholestadien-3 beta-ol as sole monohydroxy sterol and halistanol sulfate as major polyhydroxylated steroid derivative have been detected in Halichondria sp., a Madagascar sponge.

Animals↗