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Query: UMLS:C0338671 (Steroids)
 9,479 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The Cooperative Statistical Program was initiated in 1963, the 1st effort to evaluate a method of contraception by using pooled data from several clinics and a systematic statistical method. Progress reports were issued from 1963 through 1970. The reports provided epidemiological evidence that Lippes Loop D has the best overall performance of all the IUDs studied. Expulsion, pregnancy, and removal rates for bleeding and pain were measured. Performance rates for all these indices are better with the duration of the device. Since 1970, numbers of new IUDs have been designed and tested clinically. The aim was to improve efficacy, to make IUDs suitable for women who had never been pregnant, and to reduce the incidence of pain and bleeding. The T-shaped IUD has been found to cause lowered rates of removal for pain and bleeding. To counteract the higher pregnancy rate with this device, an antifertility agent can be added to the IUD for timed release. Steroids and copper have both been used. Clinics differ in their performance rates due to differing patient populations, differing physician experience, and differing clinic attitudes. The insertion technique is important to long-term performance.
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PMID:Historical considerations in the development of modern IUD's: patient and device selection and the importance of insertion techniques. 34 70

Nuclear extracts from the uteri of estradiol-implanted rats contain a tyrosinase-like enzyme that has three activities: monophenolase or cresolase, diphenolase or catecholase, and estrogen binding. When [3H]estradiol was used as a substrate, 3H2O was released from the A ring in the presence of copper and ascorbic acid. The optimal concentrations of these cofactors for the cresolase activity were established. The cresolase activity was lost on attempts at further purification. Estradiol binding was observed in conjunction with the enzymatic activity and was dependent on the presence of ascorbic acid and copper. The most potent inhibitors of 3H2O release from [3H]estradiol were those with a dihydroxyphenol moiety. The reaction was also sensitive to sulfhydryl reagents. These features of the enzyme are distinctive from other oxidases capable of attacking the aromatic ring of estrogens.
Steroids 1992 May
PMID:Tyrosinase-like activity and estradiol binding in rat uterine nuclear extracts. 148 87

As part of continuing studies on the synthesis of new, biologically interesting 11 beta-substituted steroidal spirolactones, we describe here the competition between 10 beta-propargylation and 11 beta-allenylation. Grignard addition of allenyl magnesium bromide to an appropriate 5,10-epoxy-9(11)-olefin provides 10 beta-propargylation or 11 beta-allenylation. The role of the catalytic effect of copper chloride and of the solvent is evaluated. Confirmation of the structural assignments of these new 3,3-ethylenethioxy-10 beta-propargyl (or 11 beta-allenyl)-19-nor-17 alpha-pregna-4,9-diene-21,17-carbolactones is reported.
Steroids 1991 Nov
PMID:Synthesis of new 10 beta-propargylic and 11 beta-allenic steroidal spirolactones. 181 22

The concentrations of selenium, zinc, and copper were determined in whole blood, plasma, and leucocytes in 20 patients with relatively mild Crohn's disease, nine of whom were being treated with steroids, and compared with those of a control group. There was a significant decrease in the concentration of selenium in the leucocytes as well as in whole blood and plasma in the patients. Steroids seemed to affect only the concentrations of zinc and copper in plasma. The concentrations of copper and zinc in whole blood, plasma, and leucocytes in patients not taking steroids were not significantly different from those of the control group. The observations suggest that those patients with an apparently satisfactory whole body concentration of copper and zinc may still be at risk of a decrease in the body content of selenium.
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PMID:Reduced concentrations of selenium in mild Crohn's disease. 335 Sep 80

4-Methoxyequilin and 2-methoxyequilin were synthesized from the corresponding 4-bromoequilin and 2-iodoequilin derivatives, respectively, by nucleophilic displacement of halogen with methoxide ion in the presence of copper (II) chloride and 15-crown-5-ether. 4-Bromoequilin was prepared by reacting equilin with one equivalent of N-bromoacetamide. 2-Iodoequilin was prepared by reductive dehalogenation of 2,4-diiodoequilin, which in turn was obtained by treatment of equilin with two equivalents of iodine in methanolic ammonium hydroxide solution. 4-Methoxy-equilenin and 2-methoxyequilenin were prepared from the corresponding 4-iodo- and 2-iodo-7 epsilon, 8 epsilon-epoxyestrone derivatives, respectively. Nucleophilic displacement of iodine with methoxide ion was carried out as described earlier with simultaneous aromatization of the B ring leading to 4- and 2-methoxyequilenin derivatives. Alternatively, 4-methoxyequilenin was obtained from 4-methoxyequilin by selenium dioxide oxidation.
Steroids
PMID:Synthesis of 2-methoxy and 4-methoxy equine estrogens. 345 53

Two preparative chemical methods for aromatization of 19-nor-delta 4-3-oxosteroids are described. The first method consists of an oxidative aromatization of 19-nor-delta 4-3-oxosteroids with iodine-ceric ammonium nitrate in methanol to give a mixture of 3-methoxy ring-A aromatized derivatives consisting of the desired product, the delta 9,11 derivative, the 6-oxo derivative as well as some ring-A iodinated material. Conversion of this material to a mixture of the 3-methoxy ring-A aromatized derivative and its 6-oxo derivative was achieved by catalytic hydrogenation. Finally, reduction of the 6-oxo function with triethylsilane in trifluoroacetic acid gave the 3-methoxy-17-trifluoroacetate ring-A aromatized derivative as a single product. In the second method, reaction of 19-nor-delta 4-3-oxosteroids with copper (II) bromide in acetonitrile at room temperature resulted in aromatic steroids in a single step in excellent yields. The second method was used in the first practical chemical synthesis of a 6-dehydroestrogen from a 19-nor-delta 4,6-3-oxosteroid.
Steroids 1994 Nov
PMID:Preparative chemical methods for aromatization of 19-nor-delta 4-3-oxosteroids. 770 37

Nuclear extracts from estradiol-treated rat uteri which contain type II estrogen binding sites have recently been found to also contain a tyrosinase-like estradiol metabolizing activity. A recent study suggested that both the binding and enzymatic activities are significantly increased in the presence of micromolar concentrations of copper and ascorbate, display a number of common biochemical sensitivities, and share similar ligand/substrate binding affinities. Levels of both activities are significantly increased in uterus in response to hormone (estrogen) stimulation. These and other similarities indicate a possible relationship between the enzymatic and binding activities. A detailed chromatographic examination of these two activities in the present study revealed that while the type II sites and estradiol metabolizing activity exhibited virtually identical chromatographic properties on DEAE-high-performance liquid chromatography they are readily resolved on other chromatographic matrices, including phosphocellulose, DNA-cellulose, and S-Sepharose. These results demonstrate that type II binding sites are distinct from the tyrosinase-like enzyme activity previously described in rat uterine nuclear extracts.
Steroids 1994 Apr
PMID:Chromatographic resolution of the type II estrogen binding site and a tyrosinase-like enzymatic activity from rat uterine nuclei. 807 83

In connection with studies of alternative pathways in bile acid biosynthesis, potential intermediates in a pathway starting with 27-hydroxylation of cholesterol have been prepared in natural and deuterated forms. Established methods were used to prepare 27-hydroxycholesterol and 3 beta-hydroxy-5-cholestenoic acid. Clemmensen reduction of kryptogenin in unlabeled and deuterated solvents yielded 27-hydroxy-cholesterol and 16-oxo-5-cholestene-3 beta,27-diol, which were separated by adsorption chromatography on Unisil. The labeled 27-hydroxycholesterol and 3 beta-hydroxy-5-cholestenoic acid derived from it consisted of molecules with seven (50%), six (20%), and eight (20%) deuterium atoms, and unlabeled molecules were not detected. The acetates of 27-hydroxycholesterol and methyl 3 beta-hydroxy-5-cholestenoate were 7 alpha-hydroxylated in a copper-catalyzed reaction with tert-butylperbenzoate, and the products were purified by chromatography on Unisil. The 7 beta-epimers were obtained as side products. Labeled 3 beta,7 alpha-dihydroxy-5-cholenoic acid was prepared in the same way from 3 beta-hydroxy-5-[2,2,4,4,23-2H5]-cholenoic acid. The 3-oxo-delta 4 analogs of the 3 beta-hydroxy-delta 5 compounds were prepared by oxidation with cholesterol oxidase. The labeled products had the same isotopic composition as the starting materials. Gas chromatographic retention indices and mass spectral characteristics of the trimethylsilyl ether derivatives of the neutral steroids and the methylated acids are given for all compounds.
Steroids 1993 Mar
PMID:Synthesis of potential C27-intermediates in bile acid biosynthesis and their deuterium-labeled analogs. 847 16

In an effort to assist in the preparation of ligands for the study of the estrogen receptor (ER), we have developed a new synthesis of 7 alpha-substituted estradiols. The key step in the synthesis involves a copper-catalyzed, alpha-selective, 1,6-conjugate addition of 4-pentenyl magnesium bromide to a suitably protected 6-dehydrotestosterone derivative. Desaturation and then reductive aromatization of the resulting 7 alpha-pentenyl androgen gave the 7 alpha-pentenylestradiol in good yields. The alpha-stereoselectivity of this addition in the testosterone series, compared with the 19-nortestosterone series, is significantly improved by the presence of the C-19 methyl group, which shields the beta face from attack. A key intermediate was functionalized further by substitution with fluorine-18 to provide a potential imaging agent for positron emission tomography, and by conjugation with a BODIPY (Molecular Probes Inc., Eugene, OR, USA) fluorophore to make a fluorescent probe for the estrogen receptor. The synthesis and biological evaluation of these analogs is presented, as well as a discussion of the improvements in the synthetic procedure.
Steroids 1993 Apr
PMID:A synthesis of 7 alpha-substituted estradiols: synthesis and biological evaluation of a 7 alpha-pentyl-substituted BODIPY fluorescent conjugate and a fluorine-18-labeled 7 alpha-pentylestradiol analog. 849 5

A successful approach to the synthesis of 3 beta,15 beta-dihydroxy-5-androsten-17-one (14d) has been developed using trichloroethoxy ethers as intermediates in the synthesis of the corresponding alcohols. 3 beta-Methoxymethoxy-5,15-androstadien-17-one (10c) was prepared by a selenation/dehydroselenation strategy from 3 beta-methoxymethoxy-5-androsten-17-one (14c). Base-catalyzed reaction of trichloroethanol with 10c gave 3 beta-methoxymethoxy-15 beta-trichloroethoxy-5-androsten-17-one (14g). Under the same conditions, 3 beta-acetoxy-5,15-androstadien-17-one (10b) gave 3 beta-hydroxy-15 beta-trichloroethoxy-5-androsten-17-one (14f) which was characterized after conversion to 14g. Cleavage of the trichloroethoxy group in 14f with zinc or zinc/copper couple gave 14d. The acid-catalyzed hydrolysis of 17,17-ethylenedioxy-5,15-androstadien-3 beta-ol (15) gave 3 beta-hydroxy-5,15-androstadien-17-one (10a) as the major product along with 14d. However, addition of water to 10a in the presence of acid gave the desired product 14d in poor yield (15%).
Steroids 1996 Jan
PMID:15 beta-hydroxysteroids (Part VI). steroids of the human perinatal period: the preparation and reactions of 3 beta-hydroxy-5,15-androstadien-17-one. The synthesis of 3 beta,15 beta-dihydroxy-5-androsten-17-one and derivatives. 878 32


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