Synthesis of [19- 2H3]-analogs of dehydroepiandrosterone and pregnenolone and their sulfates

Steroids: partial synthesis in medicinal chemistry

This article reviews the progress in the chemistry of the steroids that was published between January and December 2004. The reactions and partial synthesis of estrogens, androgens, pregnanes, cholic acid derivatives, cholestanes and vitamin D analogues are covered. There are 127 references.

The identification and simultaneous quantification of 7-hydroxylated metabolites of pregnenolone, dehydroepiandrosterone, 3beta,17beta-androstenediol, and testosterone in human serum using gas chromatography-mass spectrometry

7-Hydroxy-metabolites of dehydroepiandrosterone (DHEA) and 3beta,17beta-androstenediol (AD) possess immunomodulatory and neuroprotective properties; therefore, the measurement of these steroids in patients with autoimmune diseases or disturbances in the CNS may be of interest. A gas chromatography-mass spectrometry (GC-MS) method for the determination of 7-hydroxy-metabolites of pregnenolone, DHEA, AD, and testosterone including the parent steroids was applied to serum samples from 12 adult men (27-66 years), 13 male adolescents (13-20 years), 5 boys (6-10 years), 15 women in the follicular phase of the menstrual cycle (22-45 years), 17 women in the luteal phase (22-45 years), and 4 girls (6-10 years). The steroids were age and sex dependent, but independent of the menstrual cycle. The ratio of the 7alpha-hydroxy-metabolites to their parent steroids were age dependent, exhibiting an increasing trend (p < 0.0001, ANOVA) from pregnenolone (5%) to AD (20%). The ratio of 7beta- to 7alpha-metabolites ranged from 0.6 to 1. These results are consistent with models suggesting 7alpha-hydroxylation of the parent steroid, conversion to a 7-oxo-steroid and finally to the 7beta-hydroxylated-metabolite. Partial correlations suggested that 7-hydroxylation might reduce the concentration of circulating androgens. Despite the three times lower concentration of AD-metabolites, their antiglucocorticoid, immunomodulatory, and neuroprotective effects may be comparable to that of DHEA based on their reported greater biological activity.

Synthetic Approach to 5α-Pregnanolone 19-[O-(Carboxymethyl)oxime] Derivatives

Syntheses of 5α-pregnanolone derivatives (3-hydroxy-5α-pregnan-20-ones) with 3α- and 3β-configuration and 19-[O-(carboxymethyl)oxime] group were developed, starting from 19-hydroxy-20-oxopregn-5-en-3β-yl acetate. After catalytic hydrogenation, acetylation and ketone protection, the acetyl in position 3 was removed. To obtain the 3α-derivative, nitrite epimerization of the intermediate tosylate was performed before the introduction of methoxymethyl protecting group, while the 3β-derivative was protected directly. In both series, deacetylation, oxidation to an aldehyde andO-(carboxymethyl)hydroxylamine condenzation followed. Conversion to the methyl ester, simultaneous deprotection of positions 3 and 20, and alkaline hydrolysis gave the corresponding 19-[O-(carboxymethyl)oximes]. The nine- and ten-step syntheses described herein (yields 19.5 and 7.3%, respectively) gave the target compounds, designed as haptens for immunological use.