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1.
Chemistry ; 27(14): 4588-4598, 2021 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-33026656

RESUMO

In this work, zirconium-based metal-organic framework Zr-MOF-808-P has been found to be an efficient and versatile catalyst for amide esterification. Comparing with previously reported homogeneous and heterogeneous catalysts, Zr-MOF-808-P can promote the reaction for a wide range of primary, secondary and tertiary amides with n-butanol as nucleophilic agent. Different alcohols have been employed in amide esterification with quantitative yields. Moreover, the catalyst acts as a heterogeneous catalyst and could be reused for at least five consecutive cycles. The amide esterification mechanism has been studied on the Zr-MOF-808 at molecular level by in situ FTIR spectroscopic technique and kinetic study.

2.
Molecules ; 26(6)2021 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-33809941

RESUMO

In synthetic organic chemistry, there are very useful basic compounds known as building blocks. One of the main reactions wherein they are applied for the synthesis of complex molecules is the Diels-Alder cycloaddition. This reaction is between a diene and a dienophile. Among the most important dienes are the cyclic dienes, as they facilitate the reaction. This review considers the synthesis and reactivity of one of these dienes with special characteristics-it is cyclic and has an electron withdrawing group. This building block has been used for the synthesis of biologically active compounds and is present in natural compounds with interesting properties.


Assuntos
Reação de Cicloadição , Polienos , Estrutura Molecular , Polienos/síntese química , Polienos/química , Polienos/uso terapêutico , Estereoisomerismo
3.
Int J Mol Sci ; 16(9): 23012-34, 2015 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-26404263

RESUMO

We have carried out a bibliometric study about the international scientific publications on clozapine. We have used the EMBASE and MEDLINE databases, and we applied bibliometric indicators of production, as Price's Law on the increase of scientific literature. We also calculated the participation index (PI) of the different countries. The bibliometric data have also been correlated with some social and health data from the 12 most productive countries in biomedicine and health sciences. In addition, 5607 original documents dealing with clozapine, published between 1970 and 2013, were downloaded. Our results state non-fulfilment of Price's Law, with scientific production on clozapine showing linear growth (r=0.8691, vs. r=0.8478 after exponential adjustment). Seven of the 12 journals with the highest numbers of publications on clozapine have an Impact Factor>2. Among the countries generating clozapine research, the most prominent is the USA (PI=24.32), followed by the UK (PI=6.27) and Germany (PI=5.40). The differences among countries on clozapine research are significantly related to economic variables linked to research. The scientific interest in clozapine remains remarkable, although after the application of bibliometric indicators of production, a saturation point is evident in the growth of scientific literature on this topic.


Assuntos
Antipsicóticos/uso terapêutico , Bibliometria , Clozapina/uso terapêutico , Esquizofrenia/tratamento farmacológico , Antipsicóticos/história , Pesquisa Biomédica/história , Clozapina/história , História do Século XX , História do Século XXI , Humanos , Fator de Impacto de Revistas , MEDLINE , Esquizofrenia/história
4.
Psychogeriatrics ; 14(4): 261-8, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25495088

RESUMO

Depression in the elderly is a significant health issue that has the potential to seriously affect physical and emotional well-being. Therefore, the treatment of geriatric depression is necessary. Antidepressant treatment in older depressed patients is efficacious, but differences in the effectiveness of different classes of antidepressants have not been demonstrated. However, differences in tolerability profile are most recognizable in the elderly. With ageing, a series of changes occur in the elderly that modify both the pharmacokinetics and pharmacodynamics of antidepressants and may influence the efficacy, tolerability and safety of treatment in the elderly. Comorbidities require the use of other drugs, which increases the possibility of drug-drug interactions. Given these aspects, individualized therapy for each elderly patient is needed to achieve acceptable risk-benefit ratio. Effective treatment of depression in the elderly, which may require combined pharmacological with psychosocial treatment, can decrease both morbidity and mortality; it also may lead to reduced demands on family members and on health-care and social services.


Assuntos
Antidepressivos/efeitos adversos , Depressão/tratamento farmacológico , Transtorno Depressivo/tratamento farmacológico , Medição de Risco , Idoso , Envelhecimento , Antidepressivos/uso terapêutico , Interações Medicamentosas , Humanos
5.
Angew Chem Int Ed Engl ; 53(33): 8687-90, 2014 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-24939840

RESUMO

Multisite organic-inorganic hybrid catalysts have been prepared and applied in a new general, practical, and sustainable synthetic procedure toward industrially relevant GABA derivatives. The domino sequence is composed of seven chemical transformations which are performed in two one-pot reactions. The method produces both enantiomeric forms of the product in high enantiopurity as well as the racemate in good yields after a single column purification step. This protocol highlights major process intensification, catalyst recyclability, and low waste generation.


Assuntos
GABAérgicos/química , Compostos Inorgânicos/química , Compostos Orgânicos/química , Aminobutiratos/síntese química , Aminobutiratos/química , Catálise , Ciclização , GABAérgicos/síntese química , GABAérgicos/isolamento & purificação , Hidrólise , Oxirredução , Estereoisomerismo
6.
J Org Chem ; 78(14): 7068-75, 2013 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-23808573

RESUMO

Polyhydroxylated pyrrolidines have been synthesized in a one-pot procedure by the addition of an organometallic reagent to isoxazolidines obtained by a 1,3-dipolar cycloaddition between nitrones and vinylsulfones. This method highlights sulfone reactivity and provides an easy approach for the preparation of chiral pyrrolidines using cyclic imines as key intermediates.


Assuntos
Pirrolidinas/síntese química , Conformação Molecular , Pirrolidinas/química
7.
Actas Esp Psiquiatr ; 41(6): 349-60, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24203507

RESUMO

OBJECTIVES: We carried out a bibliometric study on the scientific publications in relation to atypical antipsychotic drugs (AADs) in Spain. METHODS: We used the EMBASE and MEDLINE databases and we applied some bibliometric indicators of paper production and dispersion (Price's law and Bradford's law, respectively). We also calculated the participation index of the different countries and correlated the bibliometric data with some social and health data (total per capita expenditure on health and gross domestic expenditure on research and development). RESULTS: We collected 656 original papers published between 1988 and 2011. Our study results fulfilled Price's law with scientific production on AADs showing exponential growth (correlation coefficient r = 0.9693, vs. r = 0.9177 after linear adjustment). The most widely studied drugs were risperidone (181 papers), olanzapine (143), clozapine (94), and quetiapine (74). Division into Bradford zones yielded a nucleus occupied by the European Psychiatry and European Neuropsychopharmacology (70 articles). Totally 194 different journals were published, with 5 of the first 10 used journals having an impact factor being greater than 4. CONCLUSION: The publications on AADs in Spain have undergone exponential growth over the studied period, without evidence of reaching a saturation point.


Assuntos
Antipsicóticos/uso terapêutico , Editoração/estatística & dados numéricos , Bibliometria , Pesquisa Biomédica , Humanos , Espanha , Fatores de Tempo
8.
Pharmaceutics ; 15(12)2023 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-38140069

RESUMO

Podophyllotoxin is a naturally occurring cyclolignan isolated from rhizomes of Podophyllum sp. In the clinic, it is used mainly as an antiviral; however, its antitumor activity is even more interesting. While podophyllotoxin possesses severe side effects that limit its development as an anticancer agent, nevertheless, it has become a good lead compound for the synthesis of derivatives with fewer side effects and better selectivity. Several examples, such as etoposide, highlight the potential of this natural product for chemomodulation in the search for new antitumor agents. This review focuses on the recent chemical modifications (2017-mid-2023) of the podophyllotoxin skeleton performed mainly at the C-ring (but also at the lactone D-ring and at the trimethoxyphenyl E-ring) together with their biological properties. Special emphasis is placed on hybrids or conjugates with other natural products (either primary or secondary metabolites) and other molecules (heterocycles, benzoheterocycles, synthetic drugs, and other moieties) that contribute to improved podophyllotoxin bioactivity. In fact, hybridization has been a good strategy to design podophyllotoxin derivatives with enhanced bioactivity. The way in which the two components are joined (directly or through spacers) was also considered for the organization of this review. This comprehensive perspective is presented with the aim of guiding the medicinal chemistry community in the design of new podophyllotoxin-based drugs with improved anticancer properties.

9.
Chemistry ; 18(51): 16283-7, 2012 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-23180552

RESUMO

Counteranion control enables the enantioselective, organo Lewis acid catalyzed Hosomi-Sakurai reaction of (hetero)aromatic aldehydes and allylsilanes using an easily handled disulfonimide precatalyst (see scheme). The key to the success of this system is to turn the usually undesired silylium ion catalysis into the desired catalytic regime and pair the cation with an enantiopure disulfonimide anion, thereby applying the concept of asymmetric counteranion-directed catalysis.

11.
Chemistry ; 16(34): 10462-73, 2010 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-20665581

RESUMO

This contribution describes the development and demonstration of the ambient-temperature, high-speed living polymerization of polar vinyl monomers (M) with a low silylium catalyst loading (≤ 0.05 mol % relative to M). The catalyst is generated in situ by protonation of a trialkylsilyl ketene acetal ((R)SKA) initiator (I) with a strong Brønsted acid. The living character of the polymerization system has been demonstrated by several key lines of evidence, including the observed linear growth of the chain length as a function of monomer conversion at a given [M]/[I] ratio, near-precise polymer number-average molecular weight (M(n), controlled by the [M]/[I] ratio) with narrow molecular weight distributions (MWD), absence of an induction period and chain-termination reactions (as revealed by kinetics), readily achievable chain extension, and the successful synthesis of well-defined block copolymers. Fundamental steps of activation, initiation, propagation, and catalyst "self-repair" involved in this living polymerization system have been elucidated, chiefly featuring a propagation "catalysis" cycle consisting of a rate-limiting C--C bond formation step and fast release of the silylium catalyst to the incoming monomer. Effects of acid activator, catalyst and monomer structure, and reaction temperature on polymerization characteristics have also been examined. Among the three strong acids incorporating a weakly coordinating borate or a chiral disulfonimide anion, the oxonium acid [H(Et(2)O)(2)](+)[B(C(6)F(5))(4)](-) is the most effective activator, which spontaneously delivers the most active R(3)Si(+), reaching a high catalyst turn-over frequency (TOF) of 6.0×10(3) h(-1) for methyl methacrylate polymerization by Me(3)Si(+) or an exceptionally high TOF of 2.4×10(5) h(-1) for n-butyl acrylate polymerization by iBu(3)Si(+), in addition to its high (>90 %) to quantitative efficiencies and a high degree of control over M(n) and MWD (1.07-1.12). An intriguing catalyst "self-repair" feature has also been demonstrated for the current living polymerization system.

12.
Angew Chem Int Ed Engl ; 48(24): 4363-6, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19437518

RESUMO

Room to swing a cat: A chiral disulfonimide has been designed as a powerful new motif for asymmetric catalysis. As a first illustration, a highly efficient and enantioselective Mukaiyama aldol reaction has been developed (see scheme). The actual catalyst is proposed to be an N-silyl imide which is generated in situ.


Assuntos
Ânions/química , Sulfonas/química , Catálise , Ciclização , Imidas/química , Isomerismo , Ácidos Fosfóricos/química
13.
Rev Psiquiatr Salud Ment (Engl Ed) ; 12(3): 170-186, 2019.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-30612921

RESUMO

The introduction of the first antidepressants in the 50s of the 20th century radically changed the treatment of depression, while providing information on pathophysiological aspects of this disease. New antidepressants drugs (agomelatine, tianeptine, vortioxetine) are providing data that give rise to pathophysiological hypotheses of depression that differ from the classic monoaminergic theory. In this sense, tianeptina, an atypical drug by its mechanism of differential action, contributes to clarify that in depression there is more than monoamines. Thus, tianeptine does not modify the rate of extracellular serotonin, so it does not increase or decrease the reuptake of serotonin. Chronic administration of tianeptine does not alter the density or affinity of more than a hundred classical receptors related to depression. Recently, a weak action of tianeptine on Mu opioid receptors has been described that could explain the release of dopamine in the limbic system and its participation in the modulation of glutamatergic mechanisms. These mechanisms support the hypothesis of the possible mechanism of action of this antidepressant. Tianeptine is an antidepressant, with anxiolytic properties, that can improve somatic symptoms. Tianeptine as a glutamatergic modulator, among other mechanisms, allows us to approach depression from a different point of view than other antidepressants.


Assuntos
Antidepressivos/uso terapêutico , Depressão/tratamento farmacológico , Tiazepinas/uso terapêutico , Antidepressivos/farmacocinética , Antidepressivos/farmacologia , Ansiedade/complicações , Ansiedade/tratamento farmacológico , Biomarcadores/metabolismo , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Cognição/efeitos dos fármacos , Depressão/complicações , Depressão/fisiopatologia , Ácido Glutâmico/metabolismo , Humanos , Sistema Hipotálamo-Hipofisário/efeitos dos fármacos , Sistema Hipotálamo-Hipofisário/fisiopatologia , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/fisiologia , Plasticidade Neuronal/efeitos dos fármacos , Tiazepinas/farmacocinética , Tiazepinas/farmacologia
14.
ChemSusChem ; 11(2): 432-438, 2018 01 23.
Artigo em Inglês | MEDLINE | ID: mdl-29139603

RESUMO

A series of highly crystalline, porous, hafnium-based metal-organic frameworks (Hf-MOFs) have been shown to catalyze the transfer hydrogenation reaction of levulinic ester to produce γ-valerolactone by using isopropanol as a hydrogen donor. The results are compared with their zirconium-based counterparts. The role of the metal center in Hf-MOFs has been identified and reaction parameters optimized. NMR studies using isotopically labeled isopropanol provide evidence that the transfer hydrogenation occurs through a direct intermolecular hydrogen transfer route. The catalyst, Hf-MOF-808, can be recycled several times with only a minor decrease in catalytic activity. The generality of the procedure has been demonstrated by accomplishing the transformation with aldehydes, ketones, and α,ß-unsaturated carbonyl compounds. The combination of Hf-MOF-808 with the Brønsted-acidic Al-Beta zeolite gives the four-step one-pot transformation of furfural to γ-valerolactone in good yield of 75 %.


Assuntos
Aldeídos/química , Biomassa , Háfnio/química , Estruturas Metalorgânicas/química , 2-Propanol/química , Catálise , Furaldeído/química , Cromatografia Gasosa-Espectrometria de Massas , Hidrogenação , Lactonas/química , Porosidade , Espectroscopia de Prótons por Ressonância Magnética
15.
Prog Neuropsychopharmacol Biol Psychiatry ; 31(4): 791-806, 2007 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-17223241

RESUMO

Sixty years ago at the Nuremberg Trials, 23 Nazi leaders were tried as war criminals, in what was known as "The Doctors' Trial". This trial exposed a perverse system of the criminal use of medicine in the fields of public health and human research. These practices, in which racial hygiene constituted one of the fundamental principles and euthanasia programmes were the most obvious consequence, violated the majority of known bioethical principles. Psychiatry played a central role in these programmes, and the mentally ill were the principal victims. The aim of the present work is to review, from the historical perspective, the antecedents of the shameful euthanasia programmes for the mentally ill, the procedures involved in their implementation and the use of mentally ill people as research material. The Nuremberg Code, a direct consequence of the Doctors' Trial, is considered to be the first international code of ethics for research with human beings, and represented an attempt to prevent any repeat of the tragedy that occurred under Nazism. Nevertheless, the last 60 years have seen continued government-endorsed psychiatric abuse and illegitimate use of psychoactive drugs in countries such as the Soviet Union or China, and even in some with a long democratic tradition, such as the United States. Even today, the improper use of psychiatry on behalf of governments is seen to be occurring in numerous parts of the globe: religious repression in China, enforced hospitalization in Russia, administration of psychoactive drugs in immigrant detention centres in Australia, and the application of the death penalty by lethal injection and psychiatric participation in coercive interrogation at military prisons, in relation to the USA. The Declaration of Madrid in 1996 constituted the most recent attempt to eradicate, from the ethical point of view, these horrendous practices. Various strategies can be used to combat such abuses, though it is uncertain how effective they are in preventing them.


Assuntos
Ética Médica , Psiquiatria/ética , Ética Médica/história , Eutanásia , História do Século XX , História do Século XXI , Holocausto/ética , Holocausto/história , Violação de Direitos Humanos/ética , Violação de Direitos Humanos/história , Humanos , Sistemas Políticos/história , Psiquiatria/história
16.
J Affect Disord ; 92(2-3): 161-70, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16530847

RESUMO

BACKGROUND: To carry out a bibliometric study on the scientific publications in relation to bipolar disorder. METHODS: Using the EMBASE and MEDLINE databases, we selected those documents whose title included the descriptors bipolar disorder, bipolar illness, bipolar patient, bipolar mani, bipolar depress, bipolar spectrum, manic-depressive, and rapid cycling. We applied some bibliometric indicators, as Price's Law on the increase of scientific literature, or the participation index (PI) of the different countries. The bibliometric data have also been correlated with some social and health data from the countries that are most prolific in biomedical scientific production, such as number of physicians, total per capita expenditure on health and overall volume of production in the field of psychiatry. RESULTS: A total of 4270 original documents published between 1980 and 2004 were downloaded, of which 1825 corresponded to aspects related to drug therapy. Our results state fulfilment of Price's Law, with scientific production on bipolar disorder showing exponential growth (correlation coefficient r = 0.947, as against an r = 0.849 after linear adjustment). The drugs most widely studied are lithium (1351 documents), valproate (544), carbamazepine (493), lamotrigine (240), and olanzapine (210). United States is the most productive country (participation index, PI = 44.2), followed by the United Kingdom (14.4), Netherlands (9.1) and France (4.1). CONCLUSION: The publications on bipolar disorder and mood stabilizers have undergone exponential growth over the last 25 years, without evidence a saturation point.


Assuntos
Bibliometria , Transtorno Bipolar/epidemiologia , Transtorno Bipolar/psicologia , Anticonvulsivantes/uso terapêutico , Antipsicóticos/uso terapêutico , Transtorno Bipolar/tratamento farmacológico , Bases de Dados como Assunto , Humanos , Incidência , Terminologia como Assunto
17.
Clin Neuropharmacol ; 29(4): 192-6, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16855420

RESUMO

OBJECTIVES: Treatment-resistant depression is a common occurrence in clinical practice as well as combination treatment with 2 different antidepressants. In the present case series, we study the effectiveness of the addition of reboxetine, during 12 weeks, to 14 outpatients diagnosed with major depressive disorder, according to Diagnostic and Statistical Manual of Mental Disorders (Fourth Edition, Text Revision) criteria, who had previously failed to respond or who had only responded partially, over a period of 6 weeks, to conventional treatment with mirtazapine. METHODS: Evaluation of antidepressant efficacy was carried out through the application of the 21-item Hamilton Depression Rating Scale (HDRS) and the Clinical Global Impressions-Global Improvement Scale (CGI-I). RESULTS: The percentages of responders (HDRS>or=50%), patients in remission (HDRS

Assuntos
Antidepressivos/uso terapêutico , Transtorno Depressivo Maior/tratamento farmacológico , Mianserina/análogos & derivados , Morfolinas/uso terapêutico , Adulto , Idoso , Idoso de 80 Anos ou mais , Antidepressivos/efeitos adversos , Resistência a Medicamentos , Quimioterapia Combinada , Feminino , Humanos , Masculino , Mianserina/efeitos adversos , Mianserina/uso terapêutico , Pessoa de Meia-Idade , Mirtazapina , Morfolinas/efeitos adversos , Reboxetina
18.
J Ethnopharmacol ; 106(3): 429-41, 2006 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-16757137

RESUMO

Don Quixote, the most outstanding novel of the Spanish literature, represents a documentary source widely used among those specialists who intend to deepen in the knowledge of the late Renaissance society. In this sense, Don Quixote has been also studied from a medical perspective, including a general therapeutical view (oils, ointments, balms, poultices, syrups and other pharmacy preparations). We have tackled Don Quixote from the phytotherapeutic and ethnopharmacological perspective, a barely explored field. In this work, we intend to study the medicinal plants used during the Cervantine time for the treatment de multiples diseases (sedatives like opium, laxatives and emetics like hellebore, tonics and irritants) and we analyze the specific herbal therapies (balms, purgatives and emetics, ointments and poultices), which Cervantes reveals to us in his novel. Among them, the rhubarb root (Rheum spp. or Rumex spp.) should be highlighted, as well as the seeds of gopher spurge (Euphorbia lathyris), chicory (Cichorium intybus) and rosemary (Rosmarinus officinalis), primary component of the famous Balsam of Fierabras. Also, we have examined the possible scientific influences, which might have inspired Cervantes in this field, mainly the work of Andrés Laguna (Dioscorides' Materia Medica).


Assuntos
Literatura Moderna/história , Medicina na Literatura , Fitoterapia/história , Pessoas Famosas , História do Século XVII , Humanos , Espanha
20.
J Atten Disord ; 20(12): 1066-1075, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-24464326

RESUMO

OBJECTIVE: The CAT (Comorbilidad en Adultos con TDAH) study aimed to quantify and characterize the psychiatric comorbidity at the time of diagnosis of ADHD in adult outpatients. METHOD: Cross-sectional, multicenter, observational register of adults with ADHD diagnosed for the first time. RESULTS: In this large sample of adult ADHD (n = 367), psychiatric comorbidities were present in 66.2% of the sample, and were more prevalent in males and in the hyperactive-impulsive and combined subtypes. The most common comorbidities were substance use disorders (39.2%), anxiety disorders (23%), and mood disorders (18.1%). In all, 88.8% patients were prescribed pharmacological treatment for ADHD (in 93.4% of cases, modified release methylphenidate capsules 50:50). CONCLUSION: A high proportion of psychiatric comorbidity was observed when adult outpatients received a first-time diagnosis of ADHD. The systematic registering of patients and comorbidities in clinical practice may help to better understand and manage the prognostic determinants in adult ADHD.


Assuntos
Transtornos de Ansiedade/epidemiologia , Transtorno do Deficit de Atenção com Hiperatividade/diagnóstico , Transtornos do Humor/epidemiologia , Transtornos Relacionados ao Uso de Substâncias/epidemiologia , Adulto , Transtorno do Deficit de Atenção com Hiperatividade/tratamento farmacológico , Transtorno do Deficit de Atenção com Hiperatividade/epidemiologia , Comorbidade , Estudos Transversais , Feminino , Humanos , Masculino , Transtornos Mentais/epidemiologia , Metilfenidato/uso terapêutico , Pacientes Ambulatoriais , Prevalência , Distribuição por Sexo , Transtornos Relacionados ao Uso de Substâncias/diagnóstico
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