Dehydroepiandrosterone acetate

The reaction of ethyl a-bromoacetate with 17-keto steroids such as estrone methyl ether or dehydroepiandrosterone acetate " under standard Reformatsky conditions is stereospecific, producing the 17 -ol in up to 80% yields. Ethyl a-bromopropionate reacts similarly but the yields are somewhat lower. 

The 17,20-glycol grouping (with or without an additional C-21 alcohol) can be cleaved to the 17-ketone by any of the four reagents. However, the presence of a 20-ketone has a marked influence on reactivity. Thus, 17a-hydroxy-20-ketones lacking additional oxygenation at C-21 are readily cleaved only by chromium trioxide. A recent report,however, claims that 17a-hydroxypregnenolone 3-acetate can be quantitatively cleaved to dehydroepiandrosterone acetate using lead tetraacetate in an aprotic solvent... 

Hydrolysis of the acetate (71) followed by Oppenauer oxidation gives B-norcholest-4-en-3-one in high yield. An analogous reaction sequence can be used to prepare B-norprogesterone and derivatives of B-nortestosterone from pregnenolone acetate and dehydroepiandrosterone acetate, respectively."" ... 

Ozonization of A -steroids usually gives complex mixtures (however, see ref. 48). Ozonolysis became a practical step in the general synthesis of B-norsteroids with the discovery that added methanol" (or formaldehyde ) improves yields significantly. Thus, Tanabe and Morisawa prepared 5/ -hydroxy-6/ -formyl-B-norsteroids (74) from cholesterol acetate, dehydroepiandrosterone acetate and pregnenolone acetate in overall yields of 64-74% by the reaction sequence represented below. 

SYNS (3-p,5-a)-3-(ACETYLOXY)ANDROSTAN-17-ONE ANDROSTAN-17-ONE, 3-(ACETYLOXY)-, (3-P,5-a)- DEHYDROEPIANDROSTERONE ACETATE EPIANDROSTERONE, DEHYDRO-, ACETATE ANDROSTEN-17-ONE, 3-p-HYDROXY-, ACETATE... 

DEHYDROCORTISONE see PLZOOO A-l-DEHYDROCORTISONE see PLZOOO DEHYDROEPIANDROSTERONE ACETATE see HJB225... 

A series of oxidative transformations with iodylbenzene as the co-oxidant of vanadyl bis(acetylacetonate) have been reported [1116-1118]. In the presence of VO(acac)2, iodylbenzene oxidizes A -steroids into epoxides a radical mechanism was suggested for this reaction. Epoxidation of cholest-5-ene-3-one occurred with high a-selectivity, while the remaining substrates gave mainly p-epoxides. Oxidation of trans-dehydroepiandrosterone acetate (818) afforded epoxide 819 (Scheme 3.323) [1116]. 

Neutral corticosteroids are prone to the formation of acid adducts [M+RCOO] in negative-ion mode [20-21]. Abundant acetate adducts are observed for steroids with a relatively acidic hydroxyl group [22]. In negative-ion TSP ionization, Kim et al. [23] observed more abundant acid adducts with decreasing pK, of the acid. Marwah et al. [24] showed signal enhancement for a variety of steroids like dehydroepiandrosterone (DHEA) and related compounds due to the addition of low concentration of acid, i.e., typically 1-5 mmol/1 formic acid, 1-8 mmol/1 acetic acid, or 0.05-0.15 mmol/1 trifluoroacetic acid, while higher acid concentrations were found to compromise the response. Formic acid was the best choice for the neutral steroids, while acetic acid is preferred for sulfate conjugates. Post-column addition of 10 nmol/1 silver nitrate resulted in a ten-fold increase in the response for androst-5-ene-3p,17P-diol. [M+Ag] is observed instead of [M+H-HjO] [24]. 

Hydroxypregnenolone acetate affords dehydroepiandrosterone quantitatively on treatment with lead tetra-acetate and calcium carbonate, and a remarkably simple synthesis of A -20-ketones is available by treatment of 17,21-diacyloxy-20-ketones with potassium acetate in hot DMF. The yield of A -steroid from prednisolone 17,21-diacetate was almost quantitative and the method is applicable to other esters and 4-en-3-ones. 

Simultaneous aspirin, benzyl alcohol, benzyl benzoate, boldenone, caffeine, calusterbne, cortisone, dehydroepiandrosterone (UV 210), fluo gonesterone, formebolone, mesterolone (UV 210), methandriol (UV 210), methenolone acetate, methyltestosterone, mibolerone, nandrolone acetate, nandrolone propionate, norethandrolone, norethindrone, norethin-drone acetate, oxandrolone (UV 210), oxymetholone, stanozolol, testolactone, testosterone acetate, testosterone propionate, trenbolone acetate Interfering ethisterone, methandrostenolone, nandrolone, testosterone... 

Form I of dehydroepiandrosterone was obtained by recrystallization from warm ethyl acetate, acetone, acetonitrile, or 2-propanol. Form II was obtained by rapid evaporation, using a vacuum from solutions in dioxane, tetrahydrofuran, or chloroform (which are higher boiling, less polar solvents) [30]. 

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