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2.
Steroids ; 64(3): 205-12, 1999 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10400381

RESUMO

The syntheses of N-desmethyl derivatives of CDB-2914 and the mono-N-desmethyl derivative of Mifepristone are described. We also describe the use of the mono-desmethyl derivatives as substrates for the synthesis of N-tritomethyl derivatives of CDB-2914 and Mifepristone with high specific activity (ca. 80 Ci/mmol), which serve as radioligands for radioimmunoassay.


Assuntos
Mifepristona/síntese química , Norpregnadienos/síntese química , Ensaio Radioligante , Espectroscopia de Ressonância Magnética , Mifepristona/química , Norpregnadienos/química , Radioimunoensaio
3.
Steroids ; 63(10): 523-30, 1998 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9800283

RESUMO

The syntheses of three 11 beta-aryl-19-norpregna-4,9-dien-3-one derivatives with 17-spirolactone and 17 beta-hydroxy-17 alpha-cyanoethyl substitutions are described. The progesterone agonist/antagonist activities of the new compounds are investigated using a recently developed tissue culture system that relies on the progesterone agonist up-regulation of the prostate-specific antigen (PSA) gene in female breast tumor cell lines. Two of the newly synthesized compounds exhibit mixed agonistic/antagonistic progestational activity.


Assuntos
Norpregnadienos/farmacologia , Progestinas/farmacologia , Feminino , Humanos , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Estrutura Molecular , Progestinas/antagonistas & inibidores , Progestinas/química , Células Tumorais Cultivadas
4.
Steroids ; 63(3): 141-5, 1998 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9558714

RESUMO

Syntheses of the 6 alpha-O-carboxymethyl ether derivatives of estrone and estradiol-17 beta and the preparation of their bovine serum albumin conjugates are described. The generation and evaluation of antisera produced from these conjugates is discussed.


Assuntos
Estradiol/imunologia , Estrona/imunologia , Soros Imunes , Vacinas Sintéticas/química , Animais , Estradiol/química , Estrona/química , Estudos de Avaliação como Assunto , Espectroscopia de Ressonância Magnética , Masculino , Estrutura Molecular , Coelhos , Soroalbumina Bovina/química
5.
Steroids ; 63(1): 50-7, 1998 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9437795

RESUMO

The syntheses of three 17 alpha-acetoxy-13 beta-ethyl-11 beta-aryl-18,19-dinorpregna-4,9-diene-3,20 diones from levonorgestrel are described. Despite their close structural similarity to the antiprogesterone CDB-2914, one of the compounds exhibits agonistic progestational activity, and the other two compounds are totally inactive.


Assuntos
Gonanos/farmacologia , Antagonistas de Hormônios/farmacologia , Progestinas/agonistas , Progestinas/antagonistas & inibidores , Animais , Bioensaio , Feminino , Gonanos/química , Levanogestrel/análogos & derivados , Levanogestrel/farmacologia , Mifepristona/análogos & derivados , Mifepristona/farmacologia , Norpregnadienos/farmacologia , Coelhos , Receptores de Glucocorticoides/efeitos dos fármacos , Receptores de Glucocorticoides/metabolismo , Receptores de Progesterona/efeitos dos fármacos , Receptores de Progesterona/metabolismo
6.
Steroids ; 59(11): 621-7, 1994 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-7701537

RESUMO

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.


Assuntos
Cetosteroides/química , Aromatase/metabolismo , Estrutura Molecular , Oxirredução
7.
Amino Acids ; 6(1): 97-105, 1994 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24190745

RESUMO

The chirospecific conversions of D-glucosamine hydrochloride and D-mannosamine hydrochloride to the configurationally stable L and D isomers of N-t-butyloxycarbonylserinal were carried out byt-butylcarbonylation followed by sodium borohydride reduction and sodium meta-periodate oxidation. Reaction of the L and D aldehydes with the Wittig reagent prepared from 4-chlorobenzyltriphenylphosphonium chloride and butyl lithium followed by catalytic hydrogenation, Jones oxidation and salt formation with dicyclohexylamine gave the DCHA salts of the D and L isomers ofp-chlorohomophenylalanine N-t-Boc in high enatiomeric excess. The optical purity of the title compounds was established by hydrolysis to the respective free amino acids, followed by chiral derivatization and HPLC analysis.

8.
J Med Chem ; 35(15): 2744-52, 1992 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-1495008

RESUMO

The antiviral/antitumor marine alkaloid dercitin was used as a lead compound to design analogues with anti-HIV and tumor inhibitory activities. Deletion of structural features contributing to cytotoxicity led to analogues with lowered T-lymphocyte toxicity profiles. One compound, 5, induced complete protection against HIV-1 infectivity in vitro at 12.5 micrograms/mL (38 microM) without T-cell toxicity up to 400 micrograms/mL. Compound 4 and 5 also inhibited the binding of HIV-1 to H-9 lymphocytes. These compounds may exert antiviral activity by a unique dual extracellular and intracellular mode of action--both preventing viral attachment to lymphocytes as well as intercalating with viral nucleic acid. Analogues with higher cytotoxicity such as 2 which retain the thiazole ring of the natural product proved effective in completely inhibiting the cell proliferation of breast, colon, and lung tumor cell lines at 1.5 microM concentration compared to a 70 microM dose level of 5-fluorouracil. A means of molecular separation of antiviral activity from cytotoxicity was thus achieved, and putative pharmacophores for antiviral and antitumor actions of the prototype molecule dercitin have been deduced. The 2-thio-9-acridinone derivatives 4 and 5 represent a new structural type exhibiting activity against HIV in vitro, serving as chemical leads in the design of anti-AIDS agents, while thiazolo[5,4-b]acridines such as 2 provide leads in the drug design of new antitumor agents.


Assuntos
Alcaloides/farmacologia , Antivirais/farmacologia , Divisão Celular/efeitos dos fármacos , HIV-1/efeitos dos fármacos , Alcaloides/química , Alcaloides/toxicidade , Antivirais/química , Antivirais/toxicidade , Células Cultivadas , Efeito Citopatogênico Viral/efeitos dos fármacos , DNA/metabolismo , Humanos , Interferon gama/biossíntese , Linfócitos/efeitos dos fármacos , Linfócitos/microbiologia , Radioimunoensaio , Relação Estrutura-Atividade , Células Tumorais Cultivadas
9.
Steroids ; 57(5): 216-21, 1992 May.
Artigo em Inglês | MEDLINE | ID: mdl-1488783

RESUMO

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.


Assuntos
Androstano-3,17-diol/análogos & derivados , Radioimunoensaio/métodos , Androstano-3,17-diol/sangue , Androstano-3,17-diol/imunologia , Especificidade de Anticorpos , Antígenos/imunologia , Humanos , Soros Imunes/biossíntese , Soros Imunes/imunologia
10.
Int J Pept Protein Res ; 29(1): 118-25, 1987 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-3570651

RESUMO

The DL-arylamino acid ethyl ester derivatives of beta-(3-pyridyl)-DL-alanine, and beta-(3-benzo[b]thienyl)-DL-alanine were synthesized by diethyl acetamidomalonate condensation with the respective arylmethyl halides followed by partial hydrolysis to the monoethyl ester and decarboxylation. Each derivative was enzymatically resolved to a separable mixture of the corresponding N-acetyl-L-amino acid and the unchanged D amino acid derivative. Acidic hydrolysis of the latter gave the corresponding D-amino acid, the optical purity of which was established by HPLC analysis of the 2,3,4,6-tetra-O-acetyl-beta-D-glucopyranosyl isothiocyanate (GITC) derivative. The free D amino acids were converted to D-BOC derivatives by reaction with di-tert-butyldicarbonate in tert-butyl alcohol, water and sodium hydroxide.


Assuntos
Alanina/análogos & derivados , Alanina/síntese química , Indicadores e Reagentes , Espectroscopia de Ressonância Magnética , Espectrofotometria Infravermelho
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