Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0338671 (Steroids)
 9,479 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Better synthetic approaches to 2alpha,3beta-dihydroxy-5alpha-cholestane and its ester derivatives, which were hitherto difficult to prepare, are reported. A satisfactory preparation of the desired trans-diequatorial 2alpha,3beta-dibenzoate, starting from the easily available corresponding cis 2alpha,3alpha-diol, has been devised. Finally, the influence of the temperature as well as of the bulkiness of the silver carboxylate on the steric course of the Prevost reaction have also been examined.
Steroids 1975 May
PMID:New synthetic routes to 2alpha,3beta-dihydroxy-5alpha-cholestane. 114 81

18-Hydroxyprogesterone is conveniently prepared from 3beta-acetoxypregn-5-en-20beta-ol by a modified route. 3beta-Acetoxy-18-iodopregn-5-en-20-one, obtained by the hypoiodite-photolysis procedure and oxidation, is treated with methanolic silver acetate to give the 18, 20-epoxy-20-methoxy derivative, which crystallises directly without need for chromatography. Hydrolysis of the 3-acetate, and a modified Oppenauer oxidation, gave 18-hydroxy-progesterone in 24% over-all yield.
Steroids 1976 Feb
PMID:Synthesis of 18-substituted steroids Part II (1). Improvements in the preparation of 18-hydroxyprogesterone. 127 91

18,20-Epoxy-11 beta,17 alpha,20 beta,21-tetrahydroxypregn-4-en-3-one was synthesized by the application of hypoiodite reaction to the cortisol acetonide. The intermediary 18-iodo derivative was converted to the 11-oxo steroid by chromic acid prior to silver ion-assisted solvolysis. Removal of the protective group with hydrochloric acid was finally carried out to give the desired 11 beta,17 alpha,18,21-tetrahydroxypregn-4-ene-3,20-dione as the hemiacetal form. 18,20-Epoxy-11 beta-17 alpha,20 beta,21- tetrahydroxypregna-1,4-dien-3-one was also prepared from prednisolone through a similar reaction sequence.
Steroids 1992 Sep
PMID:Convenient synthesis of 18-hydroxylated cortisol and prednisolone. 145 60

Analogs of 7 alpha-hydroxy-4-cholesten-3-one were prepared to ascertain structural features necessary for maximal activity of hepatic microsomal 12 alpha-steroid hydroxylase. Methyl 3 alpha,7 alpha-dihydroxy-5 beta-cholane-24-carboxylate derived from chenodeoxycholic acid was oxidized at C-3 with silver carbonate/Celite. The product was hydrolyzed and dehydrogenated with SeO2 to provide 3-oxo-7 alpha-hydroxy-4-cholene-24-carboxylic acid. 5 beta-Cholestane-3 alpha,7 alpha,25-triol and 5 beta-cholestane-3 alpha,7 alpha,12 alpha,25-tetrol were similarly oxidized at C-3 and dehydrogenated to provide 7 alpha,25-dihydroxy-4-cholesten-3-one and 7 alpha,12 alpha,25-trihydroxy-4-cholesten-3-one, respectively. The products were characterized by thin-layer and gas chromatography, ultraviolet, infrared, proton resonance and mass spectrometry.
Steroids 1984 Jul
PMID:Bile acids. LXXIII. Synthesis of analogs of 7 alpha-hydroxy-4-cholesten-3-one as substrates for hepatic steroid 12 alpha-hydroxylase. 644 66

A procedure is described for the chemical synthesis of steroidal-20-oxo-21-oic acids and -17 alpha(-hydroxy-20-oxo-21-oic acids. Corticosteroid derivatives containing the 20-oxo-21-aldehyde side chain are oxidized with freshly generated silver oxide in dilute aqueous sodium hydroxide.
Steroids 1983 Nov
PMID:An improved method for the chemical synthesis of steroidal 20-oxo-21-oic acids. 668 Sep 28

A synthetic route for labelling 6 beta-(2'-fluoro)ethyl-19-norcholest-5(10)-en-3 beta-ol (VII) with fluorine-18 was developed to evaluate the potential utility of VII as an adrenal imaging agent. 6 beta-p-Toluene-sulphonyloxymethyl-19-norcholest-5(10)-en-3 beta-ol acetate (I) was converted to the 6 beta-(2'-hydroxy)ethyl (VI) in a five-step process. The treatment of VI with N-N-diethyl (2-chloro-1,1,2,-trifluoroethyl)amine in methylene chloride and subsequent hydrolysis with base gave the required VII. Iodination of VI with triphenoxymethylphosphonium iodide followed by alkaline hydrolysis gave the 6 beta-(2'-iodo)ethyl (IX) which, on treatment with silver fluoride in acetonitrile, furnished the 6 beta-(2'-fluoro)ethyl (VII). Excellent conversion of the 6-beta-(2'-p-toluenesulphonyloxy)-ethyl (X) into VII was also achieved by heating with potassium fluoride for 2 hr in diethylene glycol in 76% yield, which is a readily applicable method for labelling with fluorine-18.
Steroids 1982 May
PMID:Fluoro norcholesterol analogues. Synthesis of 6 beta-(2'-fluoro) ethyl-19-norcholest-5(10)-en-3 beta-ol. 714 88

On treatment with methyl 2,3,4-tri-O-acetyl-1-bromo-1-deoxy-alpha-D-glucuronate and silver carbonate, tetrahydrocortisone 21-acetate gave the corresponding 3-glucosiduronate triacetyl methyl ester. This product was converted into the 20-semicarbazone which, by treatment with alkali to hydrolyze the ester functions and acid to hydrolyze the semicarbazone moiety, gave tetrahydrocortisone 3-glucosiduronic acid. The acid was converted into the crystalline barium salt and into the methyl ester. An analogous series of reactions was carried out on tetrahydrocortexolone 21-acetate. Treatment of the 20-semicarbazone of tetrahydrocortisone 3-glucosiduronic acid with potassium borohydride reduced the 11-oxo function to an 11 beta hydroxyl group; acid-catalyzed removal of the semicarbazone group produced tetrahydrocortisol 3-glucosiduronic acid which also was obtained as the barium salt and the methyl ester.
Steroids 1982 Jul
PMID:C-3 glucosiduronates of metabolites of adrenal steroids. 715 44

A method for separation and analysis of conjugates of ethynylestradiol in urine is described. Steroid conjugates are separated on a lipophilic strong anion exchanger (triethylaminohydroxypropyl Sephadex LH-230), and phenolic steroids released by enzyme hydrolysis or solvolysis ar isolated by chromatography on the same ion exchanger. Steroids carrying an ethynyl group are isolated by chromatography on SP-Sephadex (Ag+). Ethynylestradiol is analyzed by gas chromatography-mass spectrometry of the trimethylsilyl ether, using [9,11,11,12,12-(2)H5] ethynylestradiol and internal standard.
 ...
PMID:Analysis of isomeric ethynylestradiol glucuronides in urine. 732 Jan 16

A convenient procedure for the synthesis of 5 beta-cholestane-3 alpha,7 alpha,12 alpha,25-tetrol via a modified homologation sequence of the intermediate 3 alpha,7 alpha,12 alpha-triformyloxy-24-oxo-25-diazo-25-homo-5 beta-cholane involving a homogeneous medium is described. This involves treating the intermediate alpha-diazoketone in methanol with a solution of silver benzoate in triethylamine. Grignard reaction of the resulting triformyloxy methyl homocholate yielded 5 beta-cholestane-3 alpha,7 alpha,12 alpha,25-tetrol. Large amounts of this bile alcohol were needed to further investigate the defect of cholic acid biosynthesis in patients with cerebrotendinous xanthomatosis (CTX).
Steroids 1980 Apr
PMID:A facile synthesis of 5 beta-cholestane-3 alpha,7 alpha,12 alpha,25-tetrol. 737 30

Allylic acetoxylation of androst-5-en-17-one (1) with bromine and silver acetate gave 6 alpha- and 6 beta-acetoxyandrost-4-en-17-ones [4 (3%) and 5 (12%)] and 5 alpha-bromo-6 beta-acetoxy steroid 8 (4%) along with the expected product 4 beta-acetoxy derivative 2 (45%). Treatment of 5 alpha,6 beta-bromide 12, an intermediate of the acetoxylation reaction, with silver acetate also produced the acetates 2, 4, 5, and 8 in relative yields similar to those above. These results indicate that the 6-acetates 4 and 5 are produced through a competing pathway involving formation of a bridged carbonium ion 13 followed by attack of an acetate anion. Oxidation of the axial allylic alcohol, 5-en-4 beta-ol 3, with Jones reagent yielded no trace of the previously reported androst-5-ene-4,17-dione (18) but instead gave a 1:4 mixture of 5 beta,6 beta-epoxy-4-one 16 and 4 beta,5 beta-epoxy-6-one 17 in high yield. In contrast, a 1:4 mixture of androst-4-ene-6,17-dione (10) and compound 18 was obtained upon treatment with chromium trioxide in pyridine. Similar results were also found with the oxidation of another axial allylic alcohol, 4-en-6 beta-ol 7.
Steroids 1995 Aug
PMID:Competing pathway involved in allylic acetoxylation of androst-5-en-17-one, and oxidation of allylic alcohols with chromium oxides. 853 91


1 2 3 Next >>