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Nuclear magnetic resonance is a technique that is widely used for elucidating and characterizing organic substances. Organofluorine substances have applications in many areas from drugs to liquid crystals, but their NMR spectra are often challenging due to fluoride coupling with other nuclei. For this reason, NMR spectra of this class of substances are not commonly covered in undergraduate and graduate chemistry courses and related fields. Thus, the aim of this work was the presentation and discussion of 1H, 13C, and 19F NMR spectra of eleven organofluorine substances which, in the case of 1H and 13C nuclei, showed classic patterns of first-order coupling and the effects of the fluorine nucleus in different chemical and magnetic environments. In addition, the observation of long distance coupling constants was possible through the use of apodization functions in the processing of the spectra. It is expected that the examples presented herein can be utilized and discussed in undergraduate and graduate NMR spectroscopy disciplines and thus improve the teaching and future research of organofluorine compounds.

The paper traces a panorama of the development of new drugs and hopes to contribute for Brazil to become a player in the discovery of new drugs. Brazil is the sixth world market retail consumer of medicines prone to expansion, has a pharmaceutical industry focused on the production of generics and a very large number of undergraduate courses in Pharmacy. The national industry has grown over the last decade after the Generics Act 9787/99. Despite these positive aspects, a number of bottlenecks prevent Brazilian pharmaceutical industry to invest in the development of new drugs. There are, however, a number of initiatives to reduce the dependence on imported generic drugs. It is a very good start for the development of new pharmaceutical drugs.

Simaba guianensis subesp. ecaudata (Simaroubaceae) is a tree found in the Brazilian Amazon. This work describes for the first time the fractionation of stems of this species that resulted in the isolation of the cytotoxic triterpene piscidinol A, the alkaloid 9-methoxycanthin-6-one, caryophyllene oxide, also isolated for the first time from this species and a new alkaloid (6-methoxy-(9H-β-carbolin-1-il)-(Z)-2-propenoic acid). Quantification of 9-methoxycanthin-6-one in different extracts and fractions of stems of S. guianensis by high performance liquid chromatography was also performed. The concentration of 9-methoxycanthin-6-one in methanolic and aqueous extracts were inferior to the known cytotoxic concentration of this compound.

Prof. Ernest Wenkert's connections with Brazil on this side of the Atlantic Ocean involved two important links: Profs. Jayr de Paiva Campello and Otto R. Gottlieb. The former, along with Prof. Giuseppe Cilento, was one of those responsible for setting up the Institute of Chemistry of UNICAMP, while Otto Gottlieb was the great pioneer of Natural Products Chemistry in Brazil. The bridge between these two professors and Wenkert paved the way for several Brazilian chemists to visit the USA, and was also important for bringing some PhDs to Brazil.

The main objective of this paper is to start and stimulate reflection, discussion and proposing actions that allow Chemistry in Brazil contribute to a prosperous, safer and better future for the nation.

The use of microwave in chemistry has known benefits over conventional heating methods, e.g. reduced reaction times, chemical yield improvement and the possibility if reducing or eliminating the use of organic solvents. We describe herein a procedure for the nitration of salicylaldehyde in water using a domestic microwave oven, which can be used as an experiment in the undergraduate chemistry laboratory. The experiment involves safe and rapid preparation and identification of the position isomers by thin layer chromatography and 1H NMR, or by their melting points.

This article describes the preparation of 5-nitroisatin and of 5-chloroisatin from isonitrosoacetanilide in a single step, using readily available and inexpensive reagents. These reactions require around 90 minutes and may be carried out as an undergraduate experiment, providing an opportunity to discuss the electrophilic aromatic substitution mechanism, as well as spectroscopic techniques for product identification.

This work describes the historical importance and the use of hallucinogenic plants by different civilizations. A comparison between three Brazilian plants whose active principle is N,N-dimethyltriptamine (DMT), and three plant species native to Europe whose active principles are tropanic alkaloids was carried out and we observed these plants promoted different types of hallucinations.

Protein kinases are one of the largest protein families and they are responsible for regulation of a great number of signal transduction pathways in cells, through the phosphorylation of serine, threonine, or tyrosine residues. Deregulation of these enzymes is associated with several diseases including cancer, diabetes and inflammation. For this reason, specific inhibition of tyrosine or serine/threonine kinases may represent an interesting therapeutic approach. The most important types of protein kinases, their structural features and chemical inhibitors are discussed in this paper. Emphasis is given to the small-molecule drugs that target the ATP-binding sites of these enzymes.

The chaoolmugra oil is one of the oldest medicines used for leprosy until the development of sulfas. In Brazil, it is known as sapucainha oil that is obtained from Carpotroche brasilienesis seeds (Flacourtiaceae). Chemical and medicinal studies of sapucainha oil were introduced in Brazil by Peckolt, Cole and Cardoso which showed that major ciclopentenyl fatty acids as chaulmoogric, hydnocarpic and gorlic were responsible for its bactericidal activity. In this work, a method for quantification of sapucainha oil acidic fraction by HRGC was established using methyl n-heptadecanoate as internal standard. The oil chemical stability was investigated by the use of GC-MS, IR, ¹H and 13C NMR and showed that the main degradation products belong to the cyclopentenyl moiety oxidation.

The Brazilian Chemical Society - SBQ has made substantial contributions to the formation of qualified human resources at all levels since its foundation in 1977. Several papers addressing this subject have been published in Quimica Nova by different authors over the last years. In this paper, we discuss the present need for "Curriculum Guidelines" for undergraduate education in Chemistry with actions to be taken in accord with the Principles of Green Chemistry and Sustainability.

The effect of microwave (MW) irradiation on the crystalline structure of two natural clays and one commercial clay, Montmorillonite K10, was analyzed comparing the X-ray diffraction, N2 isotherms, NMR-MAS of 27Al and 29Si spectra of the clays before and after MW irradiation. The preparation of dioxolane ketals of isatin was used to analyze the MW effect on the catalyst activation. The yields achieved using catalysts activated by MW irradiation were lower (2 to 5%) than the yields achieved using catalysts activated by heat in a conventional oven.

Considered the best substitute for diesel, biodiesel can be blended with diesel in any ratio, bringing lots of environmental, economic and social advantages. Brazilian law Nº 11097/2005, proposes the introduction of biodiesel in to the Brazilian energy matrix, mixed with diesel at a minimum percentage of 2%. For consumers and sellers to be sure that the commercialized mixture of biodiesel:diesel contains the correct percentage, it is necessary to develop analytical methodologies to quantify the amount of biodiesel added. This work presents a fast, low-cost and simple methodology to determine the biodiesel proportion in mixtures of biodiesel:diesel, based on infrared spectroscopy.

This paper discusses of the use of the Impact Factor in the evaluation of chemistry graduate courses by CAPES and the internationalization of the Journal of the Brazilian Chemical Society and Química Nova.

Convolutamydine A is a member of a family of oxindole alkaloids isolated from the Floridian marine bryozan Amathia convoluta in 8.6x10-6 % yield. This compound is interesting as it has been described in the literature to have significant pharmacological activity. When bioactive substances are isolated in low yields, such as in the case of convolutamydine A, the use of synthetic organic chemistry to prepare larger quantities of these substances is necessary. This paper describes the isolation, structural characterization and synthesis of convolutamydine A, using readily available reagents and reaction conditions that may be applied in any organic chemistry undergraduate laboratory course.

Quimica Nova and the Journal of the Brazilian Chemical Society are two examples of successful initiatives taken by the Brazilian Chemical Society (SBQ - Sociedade Brasileira de Química), and may serve as models for the scientific societies of developing countries. Pillars of the SBQ, these two periodicals are undeniable demonstrations that idealism, utopia and dignity are the essential ingredients for transforming dreams into reality. Few believed that the Brazilian chemical community would one day have, as it does today, two scientific research periodicals indexed in the principal international data banks.

O gênero Copaifera L. é um dos mais importantes economicamente na Região Amazônica devido, principalmente, à produção dos óleos de copaíba, oléo-resinas com diversas propriedades farmacológicas confirmadas. Apesar disso, os estudos fitoquímicos com as sementes das árvores do gênero Copaifera L.são raros. Copaifera officinalis foi a primeira espécie do gênero Copaifera a ser descrita. Este trabalho descreve a composição dos extratos obtidos em hexano e em acetato de etila das sementes de C. officinalis. No extrato obtido em hexano, a análise por cromatografia em fase gasosa utilizando padrões e através de espectrometria de massas permitiu a identificação de: esqualeno, tetradecano, hexadecano, campesterol, estigmasterol e beta-sitosterol; os ácidos graxos hexadecanóico, 9-octadecenóico e octadecanóico (majoritários); e decanóico, eicosanóico, docosanóico e tetracosanóico (minoritários). Cumarina foi isolada do extrato em acetato de etila e identificada por técnicas de RMN.Copaifera L. is one of the most economically important plant genera in the Amazon Region, since it exudes a resin-oil named copaiba oil possessing several confirmed pharmacological properties. In spite of that, phytochemical studies of the seeds from this genus are rare. Copaifera officinalis L. was the first species in the genus Copaifera to be described. This paper describes the chemical composition of the hexane and ethyl acetate extracts of the seeds from this species. In the hexane extract, gas chromatography and mass spectrometry analyses enabled us to identify squalene, tetradecane, hexadecane, campesterol, stigmasterol and beta-sitosterol; hexadecanoic, 9-octadecenoic and octadecanoic acids (major substances); as well as decanoic, eicosanoic, docosanoic and tetracosanoic (minor substances) acids. Coumarin was detected in the ethyl acetate extract, isolated and identified by NMR.

The aim of this work was to develop and validate a method of analysis of biodiesel:diesel blends using HRGC-MS in SIM mode. The proposed method is applicable to biodiesel from linoleic oils, such as soybean oil. The following results were obtained: linearity over the methyl linoleate concentration range of 250-2500 mg L-1 (R² > 0.999); limits of detection and quantification of 2 and 5 mg L-1, respectively; recovery from 82 to 96% of biodiesel in diesel and repeatability < 2% (RSD). Comparison between two operators showed that it is not necessary the same operator to do the analysis.

Plant extracts are usually complex mixtures which contain several molecules of different sizes with varied functional groups. Such extracts are a challenge to the chemist of natural products. Ion exchange chromatography in non-aqueous medium, used for separation of basic or acidic fractions from plant extracts, is an important unit operation in preparative scale separations. Anionic macroporous resin in non-aqueous medium was used with success in this study for separation of the acid fraction of Copaifera multijuga (Copaiba oil), rich in labdanic diterpenes and for the methanolic extract of Croton cajucara (acetyl aleuritoric acid).

This paper reviews the recent literature on synergism, adulteration and risks of using medicinal plants. The use of copaiba and sacaca plants as well as their adulteration and side effects, are also described. In addition, the new regulations on phytotherapeutic registration in Brazil and Europe are discussed.

The polymeric material in the latex of Himatanthus sucuuba (Spruce) Woodson was identified by spectroscopic methods as cis-polyisoprene (Mn = 192; Mw = 571; Mw/ Mn = 2.97). ICP-MS analysis of microelements in the aqueous phase showed the most abundant to be Ca (354 μg/g) and Mg (250 μg/g). Carbohydrate analysis of the aqueous phase by HPLC-PAD showed arabinose, glucose, xylose, rhamnose and galactose to be the predominant saccharides.

Considering all the aspects of the principles of green chemistry, we present herein the addition reactions of amines to 1,4-naphthoquinone in water as solvent and also in solid phase. These reactions resulted in very colorful products that were easily monitored by thin layer chromatography and consequently easy to separate. Therefore, they are interesting experiments for experimental organic chemistry in the classrooms or in the laboratories.

This review details the history, chemistry and pharmacology of the Copaifera L. genus (Leguminosae - Caesalpinoideae), including copaiba oils.

This article offers an overview on the historical facts and the recent state of art of Chemistry of Natural Products which, in the course of 25 years of SBQ, have led to the present development of this area in Brazil. In addition, this article deals with the last trends on Natural Products in Brazil and also in developed countries.

This paper presents a program emphasizing ethnopharmacological approaches that could allow great success in the study of medicinal plants. The minimum ethnopharmacological research team should consist of a botanist, a chemist and a pharmacologist with each carrying the responsibility for answering in sequential fashion critical questions. The chemical composition and pharmacological properties of the very efficient medicinal plant Croton cajucara were investigated according to ethnopharmacological approaches. The study with this Croton proved to be both efficient and successful. This happy situation was only possible because a multidisciplinary team was involved getting the research done correctly. The ethnopharmacological study involving one other especies Copaifera will be cited.

The resin obtained from species of the genus Protium (Burseraceae) is formed mostly of pentacyclic triterpenes: α-amyrin and β-amyrin. The separation and purification of these triterpenes were optimized in three steps.

Wilhelm Michler lived in Brazil for seven years from 1882 to 1889, when he died. Here, he published several articles on natural products, and became a professor of Industrial Chemistry at the Escola Politécnica, in Rio de Janeiro. He was respected by colleagues and students. This article addresses this poorly known period of the life of a scientist, world-famous by the aromatic ketone that carries his name.

Regulatory pressure is increasingly focusing on the use and disposal of substances hazardous to human health and environment. In the last years efforts have also been made to introduce green chemistry concepts in undergraduate courses. In this paper we present an experiment on the oxidation reaction of borneol to camphor with bleach in acetone. This experiment is important to show undergraduate students that a cheap and non hazardous commercial product can be a useful oxidation agent of alcohols.

The impact factor of scientific journals has been used to evaluate them, as well as the quality of scientific research. This parameter was recently used by CAPES as an important criterion for the evaluation of Brazilian postgraduate courses. The main objective of this paper is to show how impact factor is calculated and to discuss its importance and limitations, with special emphasis on chemistry journals.

The impact factor of scientific journals has been used to evaluate them, as well as the quality of scientific research. This parameter was recently used by CAPES as an important criterion for the evaluation of Brazilian postgraduate courses. The main objective of this paper is to show how impact factor is calculated and to discuss its importance and limitations, with special emphasis on chemistry journals.

Himatanthus sucuuba and Plumeria rubra are used in folk medicine in Brazil to treat various ailments. The isolation of the new iridoid 15-demethylisoplumieride from the bark of Plumeria rubra L. var. acutifolia (Ait) Woodson and latex of Himatanthus sucuuba (Spruce) Woodson is reported. Other iridoid glycosides were obtained from both plants. The structures of these substances were elucidated by spectral analysis and comparison with data already reported.

Copaiba oil is a resin extracted from the trunk of trees of Copaifera species which grow in Brazil where it is widely used in popular medicine as an anti-inflammatory, antiseptic anti-bactericidal, diuretic, dermatological, expectorant, and anti-infective. The comparative study of the composition of commercial copaiba oils was carried out by high resolution gas chromatography (HRGC) and high resolution gas chromatography-mass spectrometry (HRGC-MS) analysis. The commercial oils were compared with authentic oils, collected from the southeast and northern regions of Brazil. Sixteen commercial oils were analysed and two of them revealed adulterations with fatty acids. Using the chromatographic profile of authentic copaiba species oils, it is possible to analyse commercial oils and determine the authenticity of these materials.

Os cerrados maranhenses estão localizados na Bacia Parnaibana principalmente ao leste e sul do estado. A área de estudo localiza-se na Mesorregião Oeste do Maranhão entre os municípios de Urbano Santos e Barreirinhas. As coletas foram realizadas mensalmente de setembro dc 1991 a agosto de 1992 com 12 horas de duração cada. Foram capturados 196 espécimens, 17 espécies e 6 gêneros de Anthophoridae. Centrisfoi o gênero com maior diversidade e abundância (7 espécies; 115 indivíduos), seguido de Xylocopa(4; 59) e Paratetrapedia(3; 17). Estiveram em atividade durante o ano todo, porém os maiores picos de abundância no número de indivíduos foram nos meses de outubro e novembro, que coincidiram com o período de maior floração do cerrado. Leguminosae e Malpighiaceae constiuem-se nas famílias de plantas mais visitadas pelos Anthophoridae em Barreirinhas.

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Over the past years the Brazilian Chemical Society (SBQ) has been working on different projects related to the development of Chemistry in Brazil. After a discussion throughout the country two documents have been published in Quimica Nova: "Mobilizing Axes in Chemistry" and "The Chemist's Education". Here, we describe the initial document which was the starting point for the discussion of a new series of papers published in this special issue of Quimica Nova which presents an overview of the Chemistry in our country and the perspectives and needs for the next decade.

In this paper, we present and discuss the chemist's education profile in Brazil from the points of view of the academy and the industry. We emphasize that the chemistry courses need urgently to face the following challenge: to improve the undergraduate's interdisciplinary approach, management abilities and interpersonal relationships.

As technological information is published mainly as a patent, it is fundamental for the country development to know the patent system. In this article it is presented basic information on intellectual property, in special on patent. It is showed the structure of the patent documents, and it is given notions on International Classification and patent data banks.

The problem of the dropping out of the graduate chemistry courses is not new in the Brazilian University. What are the principal factors for this dropping out? Are there rules to measure this dropping out? In this work we present our experience in the Chemistry Institute of the Federal University of Rio de Janeiro to deal with this problem.

Experiments simple, short and efficient for experimental disciplines in undergraduate courses in Chemistry are an excellent opportunity for students to consolidate the learning of theoretical concepts in classical chemical transformations. The use of a safe reagent, of low cost and easy access is the motivation for this communication, that describes the use of trichloroisocyanuric acid - a chlorinating agent used in the treatment of swimming pool water - for the chlorination of acetanilide, an intermediate in the preparation of para-chloroaniline.

Chemical investigation of Z. ekmanii resulted in the isolation of skimmianine, dictamnine, tembamide, sesamin, lupeol and beta-sitosterol. The structures were established by spectroscopic analyses. This is the first report on the phytochemical study of the roots and leaves of Z. ekmanii.