5-Androstene-3,17-dione preparation

Bacterial removal of sterol side chains is carried out by a stepwise P-oxidation, whereas the degradation of the perhydrocyclopentanophenanthrene nucleus is prevented by metaboHc inhibitors (54), chemical modification of the nucleus (55), or the use of bacterial mutants (11,56). P-Sitosterol [83-46-5] (10), a plant sterol, has been used as a raw material for the preparation of 4-androstene-3,17-dione [63-05-8] (13) and related compounds using selected mutants of the P-sitosterol-degrading bacteria (57) (Fig. 2). 

Selective conversion of l,4-androstadiene-3,l7-dione to 4-androsten-3,17-dione was achieved with (Ph Pi RuClj (SI), prepared by refluxing ruthenium... 

The formation of the GSH conjugate (or the J4 isomer of androstene-3,17-dione) is monitored at 30°C in a jacketed spectrophotometer micro-cell. The GSH-containing sodium phosphate buffer (0.1 M, 0.9 ml) of appropriate GSH concentration, is added first to the cuvette followed by the substrate in 0.05 ml ethanol (or methanol for d5-an-drostene-3,17-dione). The reaction is initiated by the addition of the enzyme preparation in the appropriate sodium phosphate buffer and... 

Subsequently the trisanellation reagent, 7-acetoxy-l,ll-dodecadien-3-one 0M>) was prepared from the bisanellation reagent (67), and the synthesis of D-homo-19-norandrosta-4-en-3-one (82) was carried out from (79) as shown below. For the A-ring formation, the unmasking of the termi double bond and hydrogenation afforded the 1,5-diketone (81), which was subjected to intramolecular aldol condensation to give D-homo-4-androstene-3,17a-dione (82 Scheme 23). 

The driving force behind the development of total syntheses for estrane and to some extent gonanes described in Chapters 2 and 3 lay in the then scarce and hence expensive steroid starting materials. The schemes that were developed made possible the elaboration of derivatives not accessible from estrone, such as gonanes with an additional carbon on the angular methyl at C13. Both androstene-17-dione and testosterone have been prepared by total synthesis. The schemes by which that was accomplished, however, were lengthy and complex. Those syntheses mainly represented a tour deforce for chemical synthesis since they were not competitive with sources of androstanes from pregnenolone or by fermentation. 

The 19-azido (93) and 19-methylthio (94) 4-androstene-3,17-diones have been found to be potent competitive reversible inhibitors (Kj = 5 nM and /fj = 1 nM respectively, for (androstenedione) = 25 nM). The same workers also discovered that 19-methanesulphonylthioandrostene-3,17-dione (95) inactivates AR in the presence of NADPH and Oj, although no kinetic or inhibitory data were presented [213]. The interaction of (94) with the active site was found to differ from that of (95) in that the latter displaces the substrate steroid from its binding site and on metabolism deactivates the enzyme, whereas (94) interacts with the substrate binding site but also with the haem-iron complex via a postulated coordinate bond. The differences in binding were deduced by examination of the ultraviolet spectral changes induced by the addition of the two inhibitors to the AR enzyme preparation. 

In a study by Albaum and Staib (1965) 4-androstene-3,17-dione was incubated with reduced nicotinamide adenine dinucleotide phosphate and liver microsomes which had been prepared from normal rats. The following metabolites were demonstrated by infrared spectroscopy 7a-hydroxy-4-androstene-3,17-dione,6) -hydroxy-4-androstene-3,17-dione, and androstane-dione. Another metabolite was very likely identical with testosterone. Differences due to sex were observed in the formation of the various metabolites. 

Monder C, Walker MC, (1970 a) Identification of 11 J , 17a-dihydroxy-3,20-dioxo-4-preg-nene-21-al-l,2- H(21-dehydrocortisol-1,2- H) and 11 j5-hydroxy-4-androstene-3,17-dione-l,2- H as contaminants in preparations of cortisol-1,2- H. Steroids 15 1-10 Monder C, Walker MC (1970 b) Interactions between corticosteroids and histones. Biochemistry 12 2489-2497... 

Figure 12 Screening of a steroid library, (a) An imprinted polymer prepared for lla-hydro-xyprogesterone. Mobile phase dichloromethane (DCM) - 0.1% acetic acid v/v, Flux 0.5mL/min. (b) An imprinted polymer prepared for lla-hydroxyprogesterone. Gradient elution, 0-25 min, DCM 0.1% acetic acid v/v 25-30 min, DCM 0.1-5% acetic acid v/v 30-40 min, DCM 5% acetic acid v/v 40-45 min, DCM 5-0.1% acetic acid v/v. Flux 0.5mL/min. (c) A control polymer prepared in the absence of template molecule. Isocratic elution, DCM 0.1% acetic acid v/v. Flux 0.5mL/min. Sample component. (1) lla-hydroxyprogesterone, (2) lla-hydroxyprogesterone, (3) 17a-hydroxyprogesterone, (4) progesterone, (5) 4-androsten-3,17-dione, (6) l,4-androstadiene-3,17-dione, (7) corticosterone, (8) cortexone, (9) 11-deoxy-cortisol, (10) cortisone, (11) cortisone-21-acetate, (12) cortisol-21-acetate. Reproduced from Ref. 58, with permission.

Step 2. The procedure for preparing 12y9-bromoacetoxy-19-nor-4-androstene-3,17-dione from 12/3-hydroxy-19-nor-4-androstene-3,17-dione is similar to that employed for the synthesis of 16 -bromoacetoxypro-gesterone from 16a-hydroxyprogesterone. °... 

In one of the earliest studies [39], we carried out the purification of A5 4 3-oxosteroid isomerase from a crude extract of Pseudomonas testosteroni by affinity pardoning in a poly(ethylene glycol)/dextran system. The macroligand was prepared by covalent coupling on poly(ethylene glycol) (PEG) of the same steroid derivative as previously described in Fig. 14.2. The resulting macroligand PEG-E,i had an inhibition constant Ki around 5 pM towards the isomerization of A5-androstene-3,17-dione, by isomerase. 

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