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1.
Sci Eng Ethics ; 6(3): 423-30, 2000 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11273465

RESUMO

Nine examples are presented illustrating the kinds of problems encountered in actual practice by conscientious engineers. These cases are drawn fom the records of the IEEE Ethics Committee, and from the experience of the ethics helpline initiated recently by the Online Ethics Center for Engineering and Science. They range from situations in which companies try to cheat one another to those in which human health and safety are jeopardized. In one case, an engineer learned that even a quiet resignation can prove very costly in a personal sense. Some ways in which professional societies might make ethical practice of engineering somewhat easier are mentioned.


Assuntos
Engenharia , Ética , Academias e Institutos , Humanos , Sociedades Científicas
3.
J Med Chem ; 30(5): 820-3, 1987 May.
Artigo em Inglês | MEDLINE | ID: mdl-3572970

RESUMO

5-Aroyl-6-substituted-1,2-dihydro-3H-pyrrolo[1,2-a]pyrrole-1-carbo xylic acids were synthesized and assayed for analgesic and antiinflammatory activity. Several of these compounds, notably the 5-(4-fluoro- and 4-chlorobenzoyl)-6-methyl derivatives 25 and 26 and the 5-(4-methyl-, 4-fluoro-, 4-chloro-, and 4-methoxybenzoyl)-6-chloro congeners 31-34 were of equal or greater potency than indomethacin as antiinflammatory and analgesic agents both in acute and chronic animal models.


Assuntos
Analgesia , Inflamação/tratamento farmacológico , Pirróis/uso terapêutico , Animais , Ácidos Carboxílicos/síntese química , Ácidos Carboxílicos/uso terapêutico , Fenômenos Químicos , Química , Espectroscopia de Ressonância Magnética , Camundongos , Pirróis/síntese química , Ratos , Relação Estrutura-Atividade
4.
J Med Chem ; 28(8): 1037-49, 1985 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-4020827

RESUMO

5-Acyl-1,2-dihydro-3H-pyrrolo[1,2-a]pyrrole-1-carboxylic acids and the homologous pyridine and azepine derivatives were synthesized and assayed for antiinflammatory and analgesic activity. 5-Benzoyl-1,2-dihydro-3H-pyrrolo-[1,2-a]pyrrole-1-carboxylic acid and the corresponding p-methoxy compound 74 were selected for evaluation as analgesic agents in humans on the basis of their high potency in the mouse phenylquinone writhing assay as well as on their minimal liability to elicit gastrointestinal erosion in rats on chronic administration. Extensive quantitative structure-activity relationship (QSAR) studies of the benzoylpyrrolopyrrolecarboxylic acids have demonstrated that the analgesic (mouse writhing) and antiinflammatory (rat carrageenan paw) potencies of these compounds are satisfactorily correlated with the steric and hydrogen-bonding properties of the benzoyl substituent(s). The 4-vinylbenzoyl compound 95, which was correctly predicted to be highly active in both assays on this basis, is undergoing advanced pharmacological evaluation in animals as a potential antiinflammatory agent.


Assuntos
Analgésicos/síntese química , Anti-Inflamatórios/síntese química , Pirróis/farmacologia , Animais , Edema/tratamento farmacológico , Masculino , Camundongos , Dor/tratamento farmacológico , Pirróis/síntese química , Ratos , Relação Estrutura-Atividade
5.
J Med Chem ; 27(5): 616-27, 1984 May.
Artigo em Inglês | MEDLINE | ID: mdl-6716399

RESUMO

A series of 2-[( alkoxycarbonyl )amino]-4(5)-phenyl-2-imidazolines was prepared and evaluated for central nervous system (CNS) effects (antidepressant, anticonvulsant, muscle relaxant, and depressant) in animal models. Some separation of those CNS activities was achieved through substitutions on the phenyl and imidazoline moieties. Halo-substituted phenyl compounds were among the most potent antidepressants in this series, while imidazole N-alkylation produced compounds with increased depressant effects (loss of righting reflex, mouse behavior). Comparison of in vitro and in vivo data for pairs of 2-[(methoxycarbonyl)amino]-4(5)-phenyl-2-imidazolines and their parent, 2-amino-4(5)-phenyl-2-imidazolines, suggests that the title compounds were prodrugs for the 2-amino-4(5)-phenyl-2-imidazolines in inhibition of norepinephrine reuptake.


Assuntos
Fármacos do Sistema Nervoso Central/síntese química , Sistema Nervoso Central/efeitos dos fármacos , Imidazóis/síntese química , Animais , Anticonvulsivantes/síntese química , Anticonvulsivantes/farmacologia , Antidepressivos/síntese química , Antidepressivos/farmacologia , Comportamento Animal/efeitos dos fármacos , Regulação da Temperatura Corporal/efeitos dos fármacos , Imidazóis/farmacologia , Indicadores e Reagentes , Masculino , Camundongos , Camundongos Endogâmicos ICR , Atividade Motora/efeitos dos fármacos , Relaxantes Musculares Centrais/síntese química , Miocárdio/metabolismo , Norepinefrina/metabolismo , Postura , Reserpina/farmacologia , Relação Estrutura-Atividade
6.
Science ; 219(4582): 257-9, 1983 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-17798255

RESUMO

Executive Order 12356, signed by President Reagan on 2 April 1982, prescribes a system for classifying information on the basis of national security concerns. The order gives unprecedented authority to government officials to intrude at will in controlling academic research that depends on federal support. As such, it poses a serious threat to academic freedom and hence to scientific advances and the national security.

7.
J Pharmacol Exp Ther ; 223(1): 68-76, 1982 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-7120129

RESUMO

Structure-activity relationships were qualitatively and quantitatively examined for 56 chemicals (e.g., derivatives of propionitrile, acrylonitrile and cysteamine) which caused duodenal ulcer and/or adrenocortical necrosis in rats. For the first time the duodenal ulcerogenic property of numerous chemicals has been studied in a rational and predictive manner. Ulcerogenic activity was most intense in the carbonitriles attached to two or three carbon backbones and diminished by shortening, lengthening, branching, unsaturating, halogenating or hydroxylating the carbon chains. Different modes of action are implied. Adrenocorticolytic potency was associated with unsaturation of the carbon chain and substitution of the nitrile by thiol or amine radicals. An action of these chemicals on the central nervous system has been suggested.


Assuntos
Córtex Suprarrenal/efeitos dos fármacos , Úlcera Duodenal/induzido quimicamente , Córtex Suprarrenal/patologia , Aminas/toxicidade , Animais , Elétrons , Feminino , Necrose/induzido quimicamente , Nitrilas/toxicidade , Ratos , Ratos Endogâmicos , Relação Estrutura-Atividade , Compostos de Sulfidrila/toxicidade
8.
J Med Chem ; 25(6): 666-70, 1982 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-6124635

RESUMO

Several 2-[(1,4-benzodioxan-2-yl)alkyl]imidazoles were prepared and evaluated for their blocking activity and relative selectivity on presynaptic (alpha 2) and postsynaptic (alpha 1) receptors in the isolated rat vas deferens. 1-Ethyl-2-[(1,4-benzodioxan 2-yl)methyl]imidazole (13) was the most selective alpha 2-adrenoceptor antagonist of the series and was, for practical purposes, devoid of alpha 1-adrenoceptor antagonist activity. The lipophilicity of 13 (log D = 2.31) indicated that it would have an excellent chance to enter the central nervous system. Compound 13 was selected for clinical evaluation as an antidepressant agent.


Assuntos
Antagonistas Adrenérgicos alfa/síntese química , Imidazóis/síntese química , Animais , Fenômenos Químicos , Química , Imidazóis/farmacologia , Técnicas In Vitro , Masculino , Contração Muscular/efeitos dos fármacos , Músculo Liso/efeitos dos fármacos , Ratos , Relação Estrutura-Atividade , Ducto Deferente/efeitos dos fármacos
9.
J Med Chem ; 24(11): 1320-8, 1981 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-7310808

RESUMO

Forty-three new 1-oxa-3,8-diazaspiro[4,5]decan-2-ones optionally substituted with 2-(3-indolyl)ethyl, 3-(2-methoxyphenoxy)-2-hydroxypropyl, or 2-(1,4-benzodioxan 2-yl)-2-hydroxyethyl at the 8 position were prepared for screening as antihypertensive agents in the spontaneous hypertensive rat. For the 8-[2-(3-indolyl)ethyl] compounds the most active were those substituted in the 4 position, where activity was at maximum with the 4-ethyl compound (1). The 8-[3-(2-methoxyphenoxy)-2-hydroxypropyl] compounds were less active than their 1,4-benzodioxane counterparts, which were tested as mixtures of erythro and threo diastereoisomers. Both the 4-ethyl-8-[2-(1,4-benzodioxan-2-yl)-2-hydroxyethyl]-substituted 38 and (S)-3-methyl-8-[3-(2-methoxyphenoxy)-2-hydroxypropyl]-substituted 42 were designed as mixed alpha- and beta-adrenergic receptor blockers. Bother compounds lowered blood pressure, but they gave no evidence of working as beta-adrenergic blockers. Examination of 8-[2-(3-indolyl)ethyl]-1-oxa-3,8-diazaspiro[4.5]-decan-2-one (8) and 3 methyl-8-[2-(1,4-benzodioxan-2-yl)-2-hydroxyethyl]-1-oxa-3,8-diazaspiro[4,5]decan-2-one (29) in the dog showed them to be alpha-adrenergic blockers. Compound 29 was primarily an alpha 2-adrenoceptor antagonist, while 8 was more skewed toward alpha 1-adrenoceptor antagonism. Tilt-response studies for evaluating the potential for producing orthostatic hypotension showed that both 8 and 29 had little potential for avoiding orthostatic hypotension at therapeutically effective doses.


Assuntos
Anti-Hipertensivos/síntese química , Compostos de Espiro/síntese química , Animais , Pressão Sanguínea/efeitos dos fármacos , Fenômenos Químicos , Química , Cães , Epinefrina/antagonistas & inibidores , Indoramina/farmacologia , Masculino , Norepinefrina/antagonistas & inibidores , Oxazóis/síntese química , Oxazóis/farmacologia , Fentolamina/farmacologia , Fenilefrina/antagonistas & inibidores , Ratos , Compostos de Espiro/farmacologia , Relação Estrutura-Atividade
10.
J Med Chem ; 24(10): 1250-3, 1981 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-7328587

RESUMO

A series of 14 vinylureidopenicillins and a series of 9 ureidopenicillins were prepared by reaction of 6-aminopenicillanic acid with vinyl isocyanates and isocyanates. These compounds were evaluated for their potential to protect ruminants against lactic acidosis. The compounds were tested for inhibition of in vitro ruminal lactic and propionic acid production, and six compounds inhibited lactic acid production to less than 10% of control at doses of 0.31 microgram/mL or lower, whereas they did not inhibit propionic acid production at doses greater than 10 micrograms/mL. The most active compounds also were screened for general antibacterial activity and were found to be weakly active against Gram-positive bacteria. The structure--activity relationships are discussed for both series. Triethylammonium 6-[3[2-(4-tert-butylphenyl)vinyl]ureido]penicillanate (4) was chosen for evaluation as an inhibitor of intraruminal lactic acidosis in vivo.


Assuntos
Antibacterianos/farmacologia , Lactatos/biossíntese , Penicilinas/farmacologia , Rúmen/metabolismo , Acidose/prevenção & controle , Animais , Antibacterianos/síntese química , Bactérias/efeitos dos fármacos , Bovinos , Ácido Láctico , Penicilinas/síntese química , Relação Estrutura-Atividade , Ureia/análogos & derivados , Ureia/síntese química , Ureia/farmacologia , Compostos de Vinila/síntese química , Compostos de Vinila/farmacologia
12.
J Pharm Sci ; 67(10): 1364-7, 1978 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-702280

RESUMO

The described simple, accurate, and precise reversed-phase high-pressure liquid chromatographic procedure is in excellent agreement with 1-octanol shake-flask partition or distribution coefficients over a 3.5 log range. A chemically bonded octadecylsilane support is persilated and coated with 1-octanol. With 1-octanol-saturated buffers as mobile phases, a stable baseline (compared to 1-octanol adsorbed on silica) is obtained rapidly, and the log relative retention times are highly correlated with unit slope to log distribution or partition coefficients obtained from the classical shake-flask procedures. Only relatively basic, unhindered pyridines deviate, probably because of binding with residual silinol sites. In addition, if the apparent pKa or pKab of an ionizable compound lies within the pH operating range of the column support, the apparent pKa or pKab usually can be determined simultaneously with log P by measuring the log distribution coefficient at several pH values. The procedure gives rapid results, requires little material, and can tolerate impurities.


Assuntos
Solubilidade , Química Farmacêutica/métodos , Cromatografia Líquida de Alta Pressão/métodos , Íons , Matemática , Octanóis , Água
13.
J Med Chem ; 21(6): 588-91, 1978 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-671458

RESUMO

A series of para-substituted N-(beta-styryl)formamides, analogues of tuberin (4a), has been prepared and assayed for antibacterial activity. The methylthio, ethoxy, and methyl analogues 4e, 4j, and 4t were about twice as active as tuberin against Mycobacterium phlei. Although tuberin lacks activity against Staphylococcus aureus, several of the analogues described were found to inhibit this organism. The phenyl group of tuberin is not a prerequisite for activity since analogues based on naphthyl or ferrocenyl groups were also active. A quantitative structure-activity relationship further implied that an aromatic group need not be present, suggesting the synthesis of the cyclohexyl and n-amyl analogues which were found to possess high activity.


Assuntos
Antibacterianos/síntese química , Estirenos/síntese química , Cinética , Testes de Sensibilidade Microbiana , Mycobacterium phlei/efeitos dos fármacos , Staphylococcus aureus/efeitos dos fármacos , Relação Estrutura-Atividade , Estirenos/farmacologia
14.
J Med Chem ; 21(6): 529-36, 1978 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-580939

RESUMO

Syntheses of tricyclic aryl-substituted 6-azauracils are described. These compounds showed anticoccidial activity when tested against Eimeria tenella and E. necatrix. Compound activity was correlated with the chemical shift of the azauracil ring proton. No correlation existed between activity and compound lipophilicity. One of the compounds, 2-(11-oxo-6,11-dihydrodibenzo[b,e]thiepin-3yl)-as-triazine-3,5(2H,4H)-dione (23), was tested extensively against E. tenella and E. brunetti both in vivo and in vitro. Compound 23 controlled mortality due to E. tenella at 62 ppm, and it afforded protection as measured by weight gain at 31 ppm. Compound 23 afforded little protection against E. brunetti. In vitro experiments with 23 showed that it exerted a coccidiostatic effect.


Assuntos
Coccidiostáticos/síntese química , Uracila/análogos & derivados , Animais , Galinhas , Coccidiose/tratamento farmacológico , Coccidiostáticos/uso terapêutico , Isomerismo , Masculino , Relação Estrutura-Atividade , Uracila/síntese química , Uracila/uso terapêutico
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