Substâncias enantiomericamente puras (SEP): a questão dos fármacos quirais

The thalidomide disaster, in the 60,s, is the most painful reminder of the importance of chirality for biological activity. After this episode, much attention has been devoted to study the correlations between toxicological and pharmacological properties and chirality. Actualy, to get a licence for a new chiral drug in EUA, European community and Japan, it is necessary to study the biological properties of each enatiomer independently. This article presents an overview about the importance of the chirality of organic compounds and its relationships with biological activity, asymmetric synthetic methodologies and market.

Os fármacos e a quiralidade: uma breve abordagem

The concepts of stereochemistry and chirality are introduced, and the ability to distinguish among the different receptors caused by one stereoselective action against chiral drugs is presented. The importance of the behaviour of chiral drugs is emphasized.

Determinação espectrofotométrica de ácido ascórbico em fármacos empregando amostragem binária em fluxo

A flow system procedure for spectrophotometric determination of ascorbic acid in drugs based on [Fe3+(SCN-)n]+3-n complex decomposition by reduction is described. The flow network was constituted by a set of three-way solenoid valves, controlled by a microcomputer running a software wrote in QuickBasic 4.5 language. The feasibility of the procedure was ascertained by determining ascorbic acid in drug samples with mass ranging from 0.0018 up to 0.0180 g. The results showed an agreement of about 7% when compared with recommended method. Other profitable features such as a standard deviation of 1.5% (n = 7) and a throughput of 120 determinations per hour was also achieved.

O processo de latenciação no planejamento de fármacos

Short review about the main aspects of prodrug design, as its objectives, applicability and importance, showing the new trends in the research for selective latent forms, namely targeted drugs.

Caracterização de polimorfismo em fármacos por ressonância magnética nuclear no estado sólido

This review aims to present some features about solid state NMR and its application in the field of pharmaceutical chemistry, for the characterization of polymorphism of pharmaceutical molecules.

Planejamento racional de fármacos baseado em produtos naturais

In the area of drug discovery, natural products represent a myriad of templates for new lead discovery. It is, however, most unlikely that the bioactive principle itself shall become a drug; it is much more likely that a medicinal chemistry project needs to be initiated as soon the potency or selectivity or specificity of the new natural product candidate has been disclosed. Brazil has an enormous biodiversity where just a few has been disclosed. Nevertheless, it urges to initiate a joint collaboration in order to circumvent a major breakdown linking between natural products and medicinal chemistry in this country. This paper is intended to encourage people to follow up one of the most pushing forward enterprise that needs to be settled: the pharmaceutical industry.

Fármacos e fitoterápicos: a necessidade do desenvolvimento da indústria de fitoterápicos e fitofármacos no Brasil

We discuss briefly the development and the present status of medicinal chemistry. In this context, we consider the therapeutic possibilities of the phytotherapy. On the basis of this analysis, the development of the phytopharmaceutical industry in Brazil is shown to be of essential importance for both the university and the Country due to the human and technological resources involved.

Aplicações da química combinatória no desenvolvimento de fármacos

Combinatorial Chemistry has become a very efficient methodology in drug research. Recent progress in combinatorial synthesis performed both in solid and solution phase have led to a change in the paradigm for the identification and optimization of lead compounds. This article gives an overview of the principal characteristics of combinatorial libraries and some examples of the application of this methodology in the identification of test compounds and lead compound optimization, either from synthetic or natural sources.

A química medicinal de N-acilidrazonas: novos compostos-protótipos de fármacos analgésicos, antiinflamatórios e anti-trombóticos

In this article are described new bioactive N-acylhydrazone (NAH) derivatives, structurally designed as optimization of aryl hydrazones precursors planned by molecular hybridization of two 5-lipoxigenase inhibitors, e.g. CBS-1108 and BW-755c. The analgesic, antiedematogenic and anti-platelet aggregating profile of several isosteric compounds was investigated by using classic pharmacological assays in vivo and ex-vivo, allowing to identify new potent peripheric analgesic lead, a new anti-inflammatory and an antithrombotic agent. During this study was discovered dozen of active NAH compounds clarifying the structure-activity relationship for this series of NAH derivatives, indicating the pharmacophore character of the N-acylhydrazone functionality.

Estratégia de simplificação molecular no planejamento racional de fármacos: a descoberta de novo agente cardioativo

In this article are described examples of the successful use of molecular simplification strategy in the discovery of new drugs from bioactive natural products and synthetic compounds. The discovery of a new cardiotonic derivative (37, 2-thienylidene-3,4-methylenedioxybenzoylhydrazine; LASSBio-294), efficiently synthesized from Brazilian natural product and structurally designed by molecular simplification of active pyridazinone compounds reported in the literature, is described. A brief description of the pharmacological profile of this new cardiotonic lead-compound, belonging to the N-acylhydrazone (NAH) class, is also reported herein.

Química Medicinal: 25 anos de planejamento racional de fármacos

The Sociedade Brasileira de Química is commemorating its 25th anniversary, and this paper is intended to draw an overview of the Brazilian Medicinal Chemistry over all these years. In 1977 Brazil had almost no activities at all in the field, albeit many efforts were already on the way for encouraging Brazilian Scientists to enter the area. Among many different endeavours to help medicinal chemists to fulfil their proposals and the establishment of an on-going research with the help of networks, the Sociedade Brasileira de Química created, in 1991, its own Division on Structure and Activity Relationship, which became the Division of Medicinal Chemistry, in 1997.

Introdução a modelagem molecular de fármacos no curso experimental de química farmacêutica

Molecular Modeling is an important tool in drug design and it is very useful to predict biological activity from a library of compounds. A wide variety of computer programs and methods have been developed to visualize the tridimensional geometry and calculate physical properties of drugs. In this work, we describe a practical approach of molecular modeling as a powerful tool to study structure-activity relationships of drugs, including some antibacterials, hormones, cholinergic and adrenergic agents. At first, the students learn how to draw 3D structures and use them to perform conformational and molecular analysis. Thus, they compare drugs with similar pharmacological activity by superimposing one structure on the top of another and evaluate the geometry and physical properties.

Fármacos no meio ambiente

Pharmaceutical drugs have been detected in sewage treatment plants, surface waters, underground waters and potable waters. Some investigations have been conducted in several countries such as Germany, Brazil, Canada, United States, The Netherlands, England and Italy. Patients and animals excrete part of pharmaceuticals used for human and veterinary medicine after administration in domestic sewage or on the soil. Drugs residues which have not been completely removed during passage through a sewage treatment plant (STP) enter the aquatic environment. The effects of such residual drugs in terrestrial and aquatic organisms are scarcely known.

Caracterização e estabilidade físico-química de sistemas poliméricos nanoparticulados para administração de fármacos

Polymeric nanoparticle systems such as nanocapsules and nanospheres present potential applications for the administration of therapeutic molecules. The physico-chemical characteristics of nanoparticle suspensions are important pre-requisites of the success of any dosage form development. The purpose of this review is to present the state of the art regarding the physico-chemical characterization of these drug carriers, in terms of the particle size distribution, the morphology, the polymer molecular weight, the surface charge, the drug content and the in vitro drug release profiles. Part of the review is devoted to the description of the techniques to improve the stability of colloidal systems.