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At least 19 recordsLinked to original sources

Urinary steroids from a newborn human infant. Identification of 2 alpha-hydroxy-4-pregnene-3,20-dione, 3 beta,15 beta-dihydroxy-5-pregnen-20-one and 3 beta,15 alpha-dihydroxy-5-pregnen-20-one.

Urinary steroids from healthy newborn human infants were analyzed by gas-liquid chromatography and gas-liquid chromatography-mass spectrometry. The identification of 2 alpha-hydroxy-4-pregnene-3,20-dione and the characterization of its 2 beta-isomer is recorded here for the first time. Mass spectrometric evidence supporting the identification of 3 beta,15 beta-dihydroxy-5-pregnen-20-one and 3 beta,15 alpha-dihydroxy-5-pregnen-20-one is also presented. Furthermore, the following 15-hydroxylated steroids were also found and identified: 3 beta,15 epsilon,16 epsilon-trihydroxy-5-androsten-17-one, 5-androstene-3 beta,15 alpha,16 alpha,17 beta-tetrol, 3 beta,15 beta,17-trihydroxy-5-pregnen-20-one and 5-pregnene-3 beta,15 epsilon,17,20 epsilon-tetrol. The origin of these 2- and 15-hydroxylated urinary steroids is discussed in relation to current knowledge of 4-pregnene-3,20-dione and 3 beta-hydroxy-5-pregnen-20-one metabolism during the human perinatal period.

17-alpha-Hydroxypregnenolone↗

15 beta-hydroxysteroids (Part V). Steroids of the human perinatal period: the synthesis of 3 beta, 15 beta, 17 alpha-trihydroxy-5-pregnen-20-one from 15 beta, 17 alpha-dihydroxy-4-pregnen-3,20-dione.

A simple three-step synthetic method is reported on the conversion of delta 4-3-ketosteroids to the corresponding 3 beta-hydroxy-delta 5-steroid analogues. 17 alpha-Hydroxy-4-pregnen-3,20-dione (10a) was used as a model to develop a method for the synthesis of 3 beta, 17 alpha-dihydroxy-5-pregnen-20-one (16). The major problem being the synthesis of 3,17 alpha-diacetoxy-3,5-pregnadien-20-one (14) was solved by acetylating using a mixture of acetic anhydride and perchloric acid. The conversion of 15 beta, 17 alpha-dihydroxy-4-pregnen-3, 20-dione (8), product of Penicillium citrinum fermentation, to the desired 3 beta,15 beta,17 alpha-trihydroxy-5-pregnen-20-one (1), is described using a modification of this method. Reaction of 8 with acetic anhydride and perchloric acid in ethyl acetate gave 3,15 beta,17 alpha-triacetoxy-3,5-pregnadien-20-one (17) which on reduction with sodium borohydride gave 5-pregnen-3 beta,15 beta,17 alpha, 20(S + R)-tetrols (18a and 18b); however, reduction of 17 with a mixture of sodium borohydride and potassium bicarbonate gave after basic hydrolysis with methanolic sodium hydroxide the desired product 3 beta,15 beta,17 alpha-trihydroxy-5-pregnen-20-one (1) in good yield (54%).

17-alpha-Hydroxypregnenolone↗

Relative in vitro effectiveness of 17 alpha, 20 beta-dihydroxy-4-pregnen-3-one and other pregnene derivatives on germinal vesicle breakdown in oocytes of ayu (Plecoglossus altivelis), amago salmon (Oncorhynchus rhodurus), rainbow trout (Salmo gairdneri), and goldfish (Carassius auratus).

The relative effectiveness of several pregnene derivatives, which had previously been identified in the ovaries of ayu (Plecoglossus altivelis), on germinal vesicle breakdown (GVBD) was investigated in vitro using folliculated oocytes of four species of teleosts, ayu, amago salmon (Oncorhynchus rhodurus), rainbow trout (Salmo gairdneri), and goldfish (Carassius auratus). Although some species differences existed in the relative effectiveness of each steroid on GVBD, 17 alpha, 20 beta-dihydroxy-4-pregnen-3-one (17 alpha, 20 beta-diOHprog) was consistently the most potent inducer of final oocyte maturation. Both progesterone and 17 alpha-hydroxyprogesterone were effective at relatively high concentrations. Of the 5 beta-reduced metabolites, 17 alpha, 20 beta-dihydroxy-5 beta-pregnan-3-one was almost as effective as 17 alpha, 20 beta-diOHprog in oocytes of amago salmon and rainbow trout, while the other 5 beta-reduced compounds (3 alpha-hydroxy-5 beta-pregnan-20-one, 17 alpha-hydroxy-5 beta-pregnane-3,20-dione, 3 alpha, 17 alpha-dihydroxy-5 beta-pregnan-20-one, 5 beta-pregnane-3 alpha, 17 alpha, 20 beta-triol, and 5 beta-pregnane-3 beta, 17 alpha, 20 beta-triol) were almost or totally ineffective at the concentrations tested (1-0.001 micrograms/ml). These bioassay results, together with previous findings on the capacity of the ovary to produce 17 alpha, 20 beta-diOHprog, indicate that 17 alpha, 20 beta-diOHprog is the natural maturation-inducing steroid hormone common to three species of Salmoniformes, ayu, amago salmon, and rainbow trout. These results, however, only suggest that 17 alpha, 20 beta-diOHprog is involved in maturation of goldfish oocytes, since supportive physiological and biochemical data are lacking. Possible regulatory roles of 5 beta-reduced metabolites on steroid-induced oocyte maturation are discussed.

Animals↗

Biosynthesis of 17,20 alpha-dihydroxy-4-pregnen-3-one, 17,20 beta-dihydroxy-4-pregnen-3-one, and 11-ketotestosterone by testicular fragments and sperm of the roach, Rutilus rutilus.

The effect of incubation time and substrate concentration on the in vitro metabolism of 17-hydroxyprogesterone by testes of the roach has been examined. There was a shift from synthesis of the 11-oxygenated androgens, 11-ketotestosterone, and androstenetrione at low substrate concentration to 17,20 alpha-dihydroxy-4-pregnen-3-one (17,20 alpha P) at high substrate. Glucuronides and sulfates were of significant importance only at low substrate and long incubation times. There was a shift from 17,20 beta-dihydroxy-4-pregnen-3-one to 17,20 alpha P with increased substrate. The results confirm that substrate affects the steroidogenic profile and that 3 hr is optimal time for such studies. Incubations of sperm with 17-hydroxyprogesterone gave predominantly 11-ketotestosterone at low substrate concentrations and 17,20 alpha P at high substrate. The synthesis of 11-ketotestosterone is demonstrated for the first time in teleost sperm.

Animals↗

18-Substituted steroids: synthesis of 18-hydroxycortisol (11 beta,17 alpha,18,21-tetrahydroxy-4-pregnene-3,20-dione) and 18-hydroxycortisone (17 alpha,18,21-trihydroxy-4-pregnene-3,11,20-trione).

The isolation of 18-hydroxycortisol from the urine of patients with primary aldosteronism was recently described and no synthetic procedure was available for its preparation. The C-13 angular methyl group of prednisolone-17 alpha,21-acetonide-11 beta-nitrite was functionalized by photolysis in the presence of oxygen to give the product 18-hydroxy-prednisolone-17 alpha,21-acetonide-18-nitrate. The 18-nitrate was reduced with zinc and ammonium acetate to the corresponding 18-hydroxy compound, 18-hydroxy-prednisolone-17 alpha,21-acetonide. Homogeneous hydrogenation with Tris(triphenyl-phosphine)rhodium (I) chloride as catalyst resulted in the formation of 18-hydroxy-cortisol-17 alpha,21-acetonide. Acid hydrolysis of the latter compound gave 18-hydroxycortisol. Oxidation of 18-hydroxycortisol-17 alpha,21-acetonide with pyridinium dichromate followed by acid hydrolysis gave 18-hydroxycortisone. The 18-hydroxylated steroids exist as the 18,21-hemiacetals. Catalytic reduction with tritium gas with Tris(triphenyl-phosphine)rhodium (I) chloride of 18-hydroxyprednisolone-17 alpha,21-acetonide and acid hydrolysis gave [1,2(3)H]18-hydroxycortisol.

Chemical Phenomena↗