Synthesis of (19E)-3 beta,7 alpha-dihydroxy-17-oxoandrost-5-en-19-al 19-(O-carboxymethyl)oxime, a new hapten for 7 alpha-hydroxydehydroepiandrosterone (3 beta,7 alpha-dihydroxyandrost-5-en-17-one).

The title compound was prepared in 11 steps from 17,17-ethylenedioxy-19-hydroxyandrost-5-en-3 beta-yl acetate. After tert-butyldimethylsilyl protection of the 19-hydroxyl group, a 7-oxo group was introduced by oxidation with 3,5-dimethylpyrazole-chromium trioxide complex, and then selectively reduced with L-Selectride to give a 7 alpha-hydroxy derivative. This partially protected triol was acetylated and desilylated to 3,7-diacetate. Subsequent oxidation with pyridine-chromium trioxide complex gave 19-aldehyde, which was transformed into the corresponding protected 19-(O-carboxymethyl)oxime. Successive ketal cleavage, deacetylation, and methyl ester splitting gave the final (19E)-3 beta,7 alpha-dihydroxy-17-oxoandrost-5-en-19-al 19-(O-carboxymethyl)oxime, designed as a hapten for 7 alpha-hydroxydehydroepiandrosterone immunoassays.

Synthesis of (15E)-17 beta-hydroxyandrost-4-en-3,15-dione 15-(O-carboxymethyl)oxime, a potential hapten for testosterone immunoassays.

The key intermediate, 15-oxandrost-5-en-3 beta, 17 beta-diyl 3-acetate 17-benzoate (10), was prepared by a five-step procedure based on the addition of 4-methoxybenzyl alcohol to 3 beta-hydroxyandrosta-5, 15-dien-17-one (1). The resulting C-15 isomers were separated as acetates. In both series, the 17-ketones were reduced to 17 beta-hydroxy derivatives, and after benzoylation, the protecting methoxyphenylmethyl group at position 15 was removed with 2,3-dichloro-5,6-dicyano-1,4-benzoquinone, leaving 15 beta-hydroxyandrost-5-ene-3 beta, 17 beta-diyl 3-acetate 17-benzoate (6) and its 15 alpha-isomer 9. After Jones oxidation, both benzoates afforded the identical ketone 10. The reaction of 10 with (O-carboxymethyl)hydroxylamine in pyridine followed by diazomethane esterification gave (15E)-15-oxandrost-5-ene-3 beta, 17 beta-diyl 3-acetate 17-benzoate 15-(O-carboxymethyl)oxine methyl ester (11). Methyl ester 11 was successively submitted to acidic deacetylation, Oppenauer oxidation, potassium hydroxide treatment and reesterification with diazomethane to give (15E)-17 beta-hydroxyandrost-4-ene-3,15-dione 15-(O-carboxymethyl) oxine methyl ester (14). After purification, ester 14 was hydrolyzed with potassium hydrogen carbonate in aqueous methanol at elevated temperature into fee testosterone 15-(O-carboxymethyl)oxine (15).

Chemical synthesis of 15 beta-hydroxytestosterone and its derivatives using a (4-methoxyphenyl)methyl protecting group.

Reaction of 3 beta-hydroxyandrosta-5,15-dien-17-one with 4-methoxybenzyl alcohol followed by acetylation gave mainly 15 beta-[(4-methoxyphenyl)methoxy]-17-oxoandrost-5-en-3 beta-yl acetate. This product was transformed by borohydride reduction and organosilyl derivatization into the orthogonally protected 17 beta-(dimethylthexylsiloxy)-15 beta-[(4-methoxyphenyl)methoxy]androst-5-en-3 beta-yl acetate and 17 beta-(dimethylisopropylsiloxy)-15 beta-[4-methoxyphenyl)methoxy]androst-5-en-3 beta-yl acetate. After deacetylation, these intermediates were submitted to Oppenauer oxidation and both yielded testosterone derivatives 17 beta-(dimethylthexylsiloxy)-15 beta-[(4-methoxyphenyl)methoxy]androst-4- en-3-one and 17 beta-(dimethylisopropylsiloxy)-15 beta-[(4-methoxyphenyl)- methoxy]androst-4-en-3-one. Removal of the (4-methoxyphenyl)methyl group from position 15 by 2,3-dichloro-5,6-dicyano-1,4-benzoquinone treatment gave the partially protected derivatives 17 beta-(dimethylthexylsiloxy)-15 beta-hydroxyandrost-4-en-3-one and 17 beta-(dimethylisopropylsiloxy)-15 beta-hydroxyandrost-4-en-3-one. After acidic deprotection, the dimethylthexylsilyl derivative yielded 15 beta-hydroxytestosterone (15 beta,17 beta-dihydroxyandrost-4-en-3-one). Dimethylisopropylsilyl derivative was converted to the corresponding 15-hemisuccinate and 15-hemiglutarate (17 beta-hydroxy-3-oxoandrost-4-en-15 beta-yl 15-hemisuccinate and 15-hemiglutarate, respectively), which were designed as model haptens for immunoassay studies.

Preparation and properties of 3-(O-(2-carboxyethyl)oxime derivatives of steroid hormones.

Mixtures of 3E and 3Z isomers of 3-(O-(2-carboxyethyl)oxime (CEO) derivatives of testosterone and 17 alpha-methyltestosterone were prepared by reaction with (O-(2-carboxyethyl))hydroxylamine. These isomers were separated after conversion into methyl esters, and mild alkaline hydrolysis recovered pure E/Z-isomers of 3-CEO derivatives of testosterone and 17 alpha-methyltestosterone. By the same method, after oximation, methylation, and separation, (20R)-20-hydroxypregn-4-en-3-one gave (3E,2OR)-20-hydroxypregn-4-en-3-one 3(O-(2-carboxyethyl)oxime and (3Z,20R)-20-hydroxypregn-4-en-3-one 3-(O-(2-carboxyethyl))oxime methyl esters. The oxidation and subsequent hydrolysis of these compounds produced 3E and 3Z isomers of the 3-CEO derivative of progesterone. Pure E/Z-isomers of 3-CEO derivatives are designed for the development of immunoanalytical systems, which make use of the bridge heterology based on the geometric isomerism.

Reversed phase high performance liquid chromatographic separation of hydroxy steroidal unsaturated esters and their hemisuccinates.

The high performance liquid chromatographic (HPLC) separation and identification of 12 isomeric and/or highly chemically related steroids with an unsaturated ester moiety at position 17 beta has been achieved. The main stereochemical features of the steroid skeleton cover 3 alpha/beta, 5 alpha/beta or delta, and 20 E/Z, bearing the alcohol or hemisuccinate group at the 3 position. The isocratic reversed phase C18 HPLC separation employed ethanol, methanol and its mixtures with water or 0.01 M phosphoric acid as the mobile phase. The best separation of the respective alcohols from their hemisuccinates has been achieved with 20% of aqueous phase content. The best separation among isomeric or related steroids has been achieved with methanol:water 8:2 and 85:15 and similar systems containing phosphoric acid.

Site of motor pathway excitation during cervical spinal stimulation.

In a set of 25 normal subjects the probable site of activation of the motor pathway was looked for using transcutaneous cervical spinal stimulation. The motor conduction time in the fastest fibres between the "spinal cord" and the wrist reached 10.79 (SD 1.17) ms when using this technique and this value was compared to the same parameter obtained with other methods: F wave mean conduction time in the established distance was 11.0 (SD 0.96) ms; the conversion of sensory to motor conduction showed 11.0 (SD 1.1) ms and H wave 10.97 (SD 1.03) ms. The conduction time through the fastest motor fibres with the spinal stimulation corresponds to the activation of the alpha-motoneuron axons near their bodies. When interpreting the results of the cortical and spinal stimulation, it is necessary to take this fact into account.

Synthetic approach to analogues of 19-norsteroids with an acyclic side chain.

Racemic 14 beta-hydroxy-3-methoxy-8 alpha,9 alpha-1,3,5(10)-estratriene-17-one (I), obtained by total synthesis, was converted into a derivative with alkoxycarbonyl-ethylenic side chain, rac-(20E)-21-methoxycarbonyl-19-nor-8 alpha,9 alpha-pregna- 1,3,5(10),20-tetraene-3,14 beta-diol 3-methyl ether (XII) using two Wittig reactions. Analogous derivatives of 5 alpha-androstane were prepared as synthetic models. In the estrane series the stereochemistry of attachement of the side chain in position 17, biological activity of some compounds, and their chromatographic properties were investigated.

Reversed-phase high-performance liquid chromatographic separation of steroids with the beta-crotonate side chain.

An isocratic high-performance liquid chromatographic separation of some ethyl 3-stereoidyl crotonates [ethyl-24-nor-20(22)-cholen-23-oate derivatives] was developed. The separations were achieved by reversed-phase chromatography (Separon Si C18) using methanol, methanol-water, methanol-0.1 M formic acid and ethanol-0.01 M aqueous phosphoric acid mixtures as mobile phases. The steroidal crotonates were detected at 230 and 240 nm.

[Effect of wood waste on the digestibility of glycides and level of volatile fatty acids in sheep]. / Vplyv drevných odpadov na strávitel'nost glycidov a úroven unikavých mastných kyselín u oviec.

Sheep were subject to an experiment concerning the effect of treated beech sawdust and thickened aqueous hydrolyzate of beech wood (xylocel) on the digestibility of glycides and on the level of volatile fatty acids (VFA) in the rumen content. The results prove that the use of treated beech sawdust as a replacer for ground barley straw favourably influenced the digestibility of monosaccharides, cellulose, lignin and total dry matter of the diet. Sawdust reduced the concentration of total VFA in the rumen content but the ratio of acetic acid to propionic acid (A:P) was lower and the energetic efficiency of the VFA produced was higher in the diet containing sawdust. The addition of urea to the diet with beech sawdust conditioned less effectively, as distinct from the case mentioned above, did not give a clear effect. Urea encouraged the digestibility of pentosanes, glucose and cellulose, but reduced the energetic efficiency of the VFA produced. Xylocel had no clear effect on the digestibility of sugars either. The higher A:P ratio and the lower energetic efficiency of the VFA produced testify to the fact that xylocel in combination with beet molasses was not a sufficient replacer of sugar-beet glycides.