Synthesis of 5 alpha-androstane-3 alpha,17 beta-diol 3- and 17-glucuronides

Synthesis of 5α-androstane-3α,17β-diol 17-O-glucuronide histaminyl conjugate for immunoassays

Simple method of preparation of 5α-androstane-3α,17β-diol 17-O-glucuronide N-histaminyl amide was developed for the construction of immunoanalytical kit. Improved method of glucuronide derivative synthesis was used, followed by hydroxybenzotriazole-dicyclohexylcarbodiimide coupling with histamine.

Glucuronidation of steroidal alcohols using iodosugar and imidate donors

We report a study of the glucuronidation of a number of important steroidal secondary alcohols. The alcohols studied are androsterone 7, epiandrosterone 8, 17-acetoxy-androstane-3alpha,17beta-diol 9, 11alpha-hydroxyprogesterone 10, and 3-benzoylestradiol 11. These were first glucuronidated using the Schmidt trichloroacetimidate method with variations in acyl substituent (viz. derivatives 2 and 3), Lewis acid catalyst and order of addition. The results are contrasted with those obtained using our recently described glycosyl iodide donor 4, catalysed either by N-iodosuccinimide (NIS) or various metal salts.

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.

Synthesis of deuterium-labeled 5 alpha-androstane-3 alpha, 17 beta-diol and its 17 beta-glucuronide

Using unlabeled androsterone as starting material, 5 alpha-[16,16-2H2]androstan-3 alpha-ol-17-one was synthesized by exchange using deuterated potassium methoxide. This labeled androsterone product was reduced by sodium borodeuteride, which gave predominantly trideuterated 5 alpha-androstane-3 alpha, 17 beta-diol. The labeled androstanediol was conjugated with glucuronide by using the Koenig-Knorr reaction with methyl-1-bromo-1-deoxy-2,3,4-tri-O-acetyl-alpha-D-glucopyranosuronate . The dominant product was identified by thermospray high-performance liquid chromatography/mass spectrometry (MS) and electrospray MS as 5 alpha-[16,16,17-2H3]androstane-3 alpha, 17 beta-diol, 17 beta-glucuronide.

A direct radioimmunoassay for 5 alpha-androstane-3 alpha,17 beta-diol 17-glucuronide

Synthesis of the 11 alpha-hemiglutaryl derivative of 5 alpha-androstane-3 alpha,17 beta-diol 17-glucuronide (androstane-diol-17G) starting from androsta-4,9(11)-diene-3,17-dione through a 10-step sequence and the preparation of its bovine serum albumin conjugate is described. By using this conjugate, antiserum was raised in rabbits which proved to be very specific for androstanediol-17G. A direct radioimmunoassay using a double antibody procedure is described for the measurement of androstanediol-17G from plasma without prior chromatography.

Synthesis of new steroid haptens for radioimmunoassay--VIII. Development and validation of a specific radioimmunoassay for serum 5 alpha-androstane-3 alpha, 17 beta-diol 17-glucuronide

5 alpha-Androstane-3 alpha, 17 beta-diol glucuronide (androstanediol-G) is a dihydrotestosterone metabolite whose serum levels are elevated in hirsute women. Current assay methods do not distinguish between the two androstanediol-G isomers, androstanediol 3-G and androstanediol 17-G. Since the production of these isomers may be influenced by different factors, we have developed a specific radioimmunoassay for androstanediol 17G. The antibody was raised against 5 alpha-androstane-3 alpha, 17 beta-diol 17-G conjugated to bovine serum albumin (BSA). [9,11(-3H]5 alpha-Androstane-3 alpha, 17 beta-diol 17-G was used for determination of procedural losses and as the labeled ligand in the assay. Unlabeled androstanediol 17-G was used as assay standard. Serum levels of total androstanediol-G, androstanediol 3-G and androstanediol 17-G were measured in 8 normal men. Total androstanediol-G levels were 16.5 +/- 5.2 nmol/l, androstanediol 17-G levels were 12.9 +/- 5 nmol/l, and androstanediol 3-G levels were 3.3 +/- 1.8 nmol/l. 77 +/- 13% of total androstanediol-G was androstanediol 17-G. These results confirm our previous findings that androstanediol 17-G is the predominant androstanediol-G isomer in human serum and suggests that 5 alpha-dihydrotestosterone (DHT) is preferentially metabolized to androstanediol 17-G.

Androgen glucuronyl transferase activity in rat liver, evidence for the importance of hepatic tissue in 5 alpha-reduced androgen metabolism

To elucidate the role of the liver in 5 alpha-reduced androgen metabolism, we used a rat liver glucuronyl transferase assay to determine the conversion of 17 beta-hydroxy-5 alpha-androstane-3-one (DHT), 5 alpha-androstane-3 alpha, 17 beta-diol (androstanediol), and androsterone to their glucuronide metabolites. Serum levels of the two isomers of androstanediol glucuronide (androstanediol 3- and 17-glucuronide) were also measured. Using 5 microM unconjugated steroid as substrate, the production rate (pmol/mg/min) for each product from its respective unconjugated steroid was 6.9 +/- 0.4 for DHT glucuronide, 101 +/- 3.3 for androstanediol 3-glucuronide, 71 +/- 2.0 for androstanediol 17-glucuronide, and 181 +/- 11 for androsterone glucuronide. Production rates for androstanediol glucuronide were 800 times greater for rat liver than for rat prostate, when examined under similar conditions. In the presence of either 0 or 5 microM unlabeled androstanediol, about 60% of the androstanediol glucuronide formed by rat liver was androstanediol 3-glucuronide. In normal male rat serum, 69 +/- 8% (mean +/- SEM) of total androstanediol glucuronide was androstanediol 3-glucuronide. We have previously shown that rat prostate forms androstanediol 17-glucuronide, but not androstanediol 3-glucuronide. The results from the present study indicate that rat liver forms both androstanediol glucuronide isomers, and does so in about the same ratio as is found in rat serum. The rate of glucuronidation is also much greater in rat liver than in rat prostate. While other sites of glucuronidation are possible, these results are consistent with the hypothesis that DHT and other unconjugated androgens formed in rat prostate are conjugated to glucuronic acid mainly in the liver.

A chemiluminescent immunoassay for the direct measurement of urinary 5 alpha-androstane-3 alpha, 17 beta-diol-glucuronide in urine

We described a chemiluminescent immunoassay (CIA) for 5 alpha-androstane-3 alpha, 17 beta-diol-glucuronide (3 alpha-diol-G) in human diluted urine. This method allowed the direct measurement in 1 microliter of urine avoiding the hydrolysis and extraction steps for sample pretreatment commonly used in routine methods. The hapten 3 alpha-diol-G was synthesized by a Koenigs-Knorr reaction. The immunogenic complex, 3 alpha-diol-G conjugated to bovine serum albumin (BSA), was employed to induce the formation of specific antibodies in New Zealand rabbits. In addition, the required chemiluminescent (CL) tracer was prepared. The characteristics of the antibody was determined as regard to specificity and sensitivity and the precision of the assay methods established. In 22 hirsute women affected by polycystic ovarian syndrome we found 3 alpha-diol-G values significantly (p less than 0.01) higher (146.28 +/- 73.77 micrograms/g of creatinine; mean +/- SD) than those observed in normal women (72.1 +/- 32.58 micrograms/g of creatinine; mean +/- SD).

Isolation and identification of androstanediol glucuronide from human plasma

[3H]Dihydrotestosterone (50 microCi) was infused into normal men and women for 8 h. It was previously shown that this was sufficient time for this material to reach a steady state. Venous plasma was obtained at 6 and 8 h, pooled, and the unconjugated steroids removed by ether extraction. The remaining plasma was adjusted to pH 4.9 and the steroid conjugate was extracted first with ethyl acetate and then with an ether-ethanol mixture. The extracts were combined and taken to dryness. Steroid sulfates were solvolyzed using dioxane, and the mixture partitioned between ether and 1% NaOH. The aqueous phase was acidified and added to an XAD-2 column, washed with water, and the glucuronide fraction eluted with methanol. The solvent was concentrated and the methanol extract was passed through a C18 Sep-Pak, filtered through an Acrodisc CR and then subjected to gradient high performance liquid chromatography [HPLC] (Nova-Pak C18, KH2PO4, pH 3, and methanol). The fractions containing steroid glucuronides were collected and esterified with diazomethane and then acetylated with acetic anhydride in pyridine. The glucuronide triacetyl methyl ester (GAME) derivatives were then run in a second HPLC system (3 Lichrosorb 5 mu columns, 4 mm x 25 cm) using a gradient of ethanol-heptane and heptane. We clearly established that this system separates 3 alpha-diol GAME conjugated at the 17 and 3 positions (44 vs 50 min) with authentic samples previously synthesized in our laboratory. We concluded that the pooled plasma contained only the 17-GAME conjugate. No significant activity of the 3-glucuronide was detected. The natural compound in circulation, therefore, is 5 alpha-androstane-3 alpha, 17 beta-diol 17-glucuronide.