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Stereochemistry control is very important in organic synthesis and it is a basic challenge in asymmetric synthesis. An approach widely used is making use of chiral auxiliary compounds. In this work it is showed the synthesis of highly optically pure rigid polycyclic compounds from the Diels-Alder adduct 1. Compounds 1-3 were prepared as described by Ito et. al. [1]. The alcohol (-)-3 was obtained by biotransformation of diketone 2 with Mucor ramosissimus, e.e.>99% (60%). The polycyclic halides 4-6 were synthesized (60-97%) after treatment of alcohol (-)-3 with NBS, NIS and, NCS in dichloromethane, respectively. Compound 7 was prepared by reaction with p-toluenesulfonic acid, whilst 8 was prepared by treatment of (-)-3 with m-chloroperbenzoic acid. The strained polycylic alcohols 9-13 will be achieved by reduction of ketones 4-8 with NaBH4. All compounds were identified by 1H and 13C NMR spectroscopy. Due to intrinsic rigidity of the synthesized polycyclic, they could be of use as chiral auxiliary agents. Prochiral substrates can be readily attached by many ways to C-3 or through hydroxyl group found in compounds 8-13. The stereo-dirigent potential of these polycyclic can also be increased by directly or indirectly introduction of many groups at position C-3, or at adjacent positions to carbonyl or hydroxyl at C-3 and C-10.

The use of microorganisms or isolated enzymes in synthetic routes has been extensively used by industry and academic research. A great advantage of biotransformation in a synthetic route is highly regio- and enatiosselective control, which can be achieved through microbial catalyzed reaction. Biotransformation is one of the most efficient methods in a production of high purity optical compounds and development of efficient routes for target molecules. Biotransformation by Mucor ramosissimus of enedione 1 gave the keto-alcohol (-)-2 with enantiomeric excess (ee)>99,9% (determined by 1H NMR with [(+)-Eu(hfc)]3) and their epimer (-)-3. Determination of the absolute configuration of epimer (-)-3 was accomplished by controlled reaction and measuring of optical rotation (scheme 1). The fungus M. ramosissimus is a promising species to perform desymmetrization of diketones with high enantioselectivity.

Recently, studies aiming to preparation of nanomaterials for application in high technology areas are very advanced in developed countries. Liquid crystals have a vast application and for that; many researches are focused on the development of these special molecules. Polyarylacetylenes are polymers that can hold helicity if polymerization of the monomer occurs in the presence of appropriate metal catalysts. The aiming of this work is to prepare side-chain crystal-liquid helicoidal chiral polymers. These systems show a molecular structure in which the mesogenic unity (pendant) is sided-attached to the polymeric chain. If a chiral substituent is incorporated to the monomer, it will induct chirality of the polymer. Glycerol [1] and cardanol [2], obtained from renewable source, were formally coupled to form the epoxide 1 that in turn was treated with 4-ethylanyline in CHCl3 at 120 oC in a sealed tube in the presence of pyridine, furnishing monomer 2 (40%). The next step it will be the enzymatic resolution of the alcohol 2 in order to achieve optical pure 2. Sequentially, from monomer 2, it is going to be synthesized the targeted stereoregular cis-trans polymer following known procedures, using [Rh(nbd)Cl]2 (nbd=2,5-norbornadiene) as the catalyst [4].

Porphyrins are very attractive compounds due to their wide application in many areas of new materials as chemical technology, ecology, medicine and, electronics. In the last years, they are also been a focus of attention owing to their implications to many photocatalytic reactions. Cardanol (isolated form cashew nut shell liquid) and glycerol (side product of biodiesel industry) are raw materials of low aggregated value; however, they hold chemical structures with functionalities that can lead to products of high commercial value to Brazilian industry. Aiming to use these chemical materials, our research group has proposed the synthesis of new hybrid molecular structures of porphyrin-cardanol-glycerol, which will be submitted to test of their photocatalytic properties. The synthetic proposal is based on the reaction of 4-hydroxybenzaldehyde (1) and epichloriridine (2) (derived from glycerol), using pyridine in dichloromethane and FeCl3 as a catalyst, under reflux and stirring. This process will provide the mixture of intermediate 3 and 4. These compounds will be attacked by the nucleophile cardanol (5) in sealed tube, using pyridine and dichloromethane at 120 ºC for 80 hours, giving the intermediate 6. After oxidation of the alcohol 6, the corresponding ketone will be achieved. Continuing the synthesis, these intermediates will separately react with pyrrol, giving the wished porphyrins that in turn will be transformed in macromolecules by treatment with Grubbs catalyst, according to methodologies already known in the literature. The previously synthesized compounds 3, 4, 5 and 6 had their structures confirmed by spectroscopy analyses of NMR (1H and 13C).

This work presents two proposals for the synthesis of halogenated aryl thiosulfonates which are of biologically interesting compounds. Inhibitors of proteases and juvenile hormone mimetizing are already successfully employed for managing pest-insects However, many of these products can be always improved in the aspects of specificity implying in low cost to the farmer. The major objective of this work is the synthesis of thiosulfonates analogues of commercial products which are inhibitors of serine-protease and juvenile hormone mimetizing compounds that can be applied as leads for production of insecticides that can contribute to the control of pest-insects in economically important plantation and stored grains. The scientific research group SINTMOLB (CNPq) is involved with studies related to the synthesis of phenolic compounds with insecticidal potential. Some important results have already been obtained and, in this new project, it is being explored the synthesis of new compounds, computational analysis, and biological tests to evaluate protease inhibitory effect.

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O objetivo principal desta pesquisa foi avaliar a qualidade das águas subterrâneas, em relação à concentração de íons fluoreto, na Região do Vale do Rio Pardo e Rio Taquari, RS. No período de dezembro de 1997 a junho de 1999, foram realizadas duas campanhas para determinação da concentração de íons fluoreto em amostras de água de 500 poços, distribuídos em 14 municípios na área de estudo. Os resultados indicaram que dos 500 poços analisados, 7,2% apresentaram valores médios na faixa ideal para flúor, 83,2% apresentaram concentrações inferiores ao valor mínimo recomendado, e 9,6 % apresentaram valores acima do limite permitido, 1,0 mg.L-1. Na região do Vale do Rio Pardo, 12,9 % dos poços apresentaram valores médios acima do limite permitido, localizando-se em uma faixa característica que parte do oeste do município de Candelária até Venâncio Aires, passando por Rio Pardo, Vera Cruz, Santa Cruz do Sul e Passo do Sobrado. Já, no caso do Vale do Rio Taquari, somente 1,4 % dos poços apresentaram esta condição. A delimitação desta faixa característica servirá de suporte ao gerenciamento dos recursos hídricos subterrâneos por parte dos órgãos estaduais competentes.

O objetivo foi quantificar a incidência de fungos em grãos de soja (Glycine max ( L.) Merrill) provenientes de cruzamentos de soja tipo alimento com soja tipo grão. A soja tipo alimento inclui a soja com sementes grandes, com peso de cem sementes (PCS) igual ou maior que 20 gramas (soja tipo hortaliça) e a soja com sementes pequenas, com PCS menor que 10 gramas (soja para consumo na forma de brotos ou "natto"). A soja tipo grão tem sementes de tamanho médio, com PCS entre 10 e 19 gramas, e é destinada à indústria para a produção de óleo e farelo. As amostras de sementes de 116 diferentes linhagens puras foram colhidas no campo em 1993 e avaliadas pelo método de papel filtro. Foram detectados os seguintes fungos: Aspergillus sp. (40,37%); Penicillium sp. (18,66%); Fusarium sp. (12,44%); Rhizopus sp. (5,71%); Cercospora sp. (1,87%) e Verticiliium sp. (1,52%). Em níveis inferiores a 1,5%, foram detectados os seguintes fungos: Alternaria sp.; Colletotrichum sp.; Trichoderma sp.; Curvularia sp.; Nigrospora sp.; Phomopsis sp.; Diplodia sp. e Monilia sp. Em um programa de melhoramento genético de soja para o consumo humano, atenção especial deve ser dada a microorganismos, especialmente aos gêneros Aspergillus sp., Penicillium sp. e Fusarium sp., uma vez que possuem capacidade para produzir substâncias que podem ser prejudiciais ao homem e aos animais.

ABSTRACT Cardanol is a constituent of Cashew Nut Shell Liquid that presents larvicidal activity against Aedes aegypti. The isolation of cardanol is somewhat troublesome, however, in this work we describe an efficient and inexpensive method to obtain it as a pure material. The compound was used as starting material to make chemical transformation leading to saturated cardanol, epoxides and, halohydrins. These derivatives were tested for toxicity against Aedes aegypti larvae. The results showed that iodohydrins are very promising compounds for making commercial products to combat the vector mosquito larvae presenting a LC50 of 0.0023 ppm after 72 h of exposure.

Abstract Chemotherapy is one of the major approaches for the treatment of cancer. Therefore, the development of new chemotherapy drugs is an important aspect of medicinal chemistry. Chemotherapeutic agents include isocoumarins, which are privileged structures with potential antitumoral activity. Herein, a new 3-substituted isocoumarin was synthesized from 2-iodo-3,5-dimethoxy-benzoic acid and oct-1-yne in a cross-coupling Sonogashira reaction followed by a copper iodide-catalyzed intramolecular cyclization as key step using MeOH/Et3N as the solvent system. The present study also evaluated the leukometry, phagocytic activity, genotoxic potential and cell death induction of three different doses (5 mg/kg, 10 mg/kg and 20 mg/kg) of this newly synthesized isocoumarin, alone and in combination with the commercial chemotherapeutic agents cyclophosphamide (100 mg/kg) and cisplatin (6 mg/kg) in male Swiss mice. The results suggest that the isocoumarin has genotoxicity and causes cell death. Noteworthy, this new compound can increase splenic phagocytosis and lymphocyte frequency, which are related to immunomodulatory activity. When combined with either cyclophosphamide or cisplatin, chemopreventive activity led to a reduction in the effects of both chemotherapeutic drugs. Thus, the new isocoumarin is not a candidate for chemotherapeutic adjuvant in treatments using cyclophosphamide or cisplatin. Nevertheless, the compound itself is an important prototype for the development of new antitumor drugs.

A maioria dos aparatos experimentais para o estudo de ondas de som estacionárias é composto por um tubo onde há um êmbolo com um microfone para captação do sinal e um alto-falante como fonte excitadora. Este mesmo êmbolo define o tamanho útil do tubo de forma manual. A interpretação correta dos fenômenos físicos relacionados a este experimento está intimamente conectada com a configuração experimental, podendo causar má interpretação. O sistema usual foi adaptado para ser automatizado e para que permitisse a movimentação do êmbolo e do microfone de forma independente. Os resultados obtidos na configuração de tubo semiaberto e fechado estão em acordo com a teoria e mostraram quais parâmetros afetavam de forma mais significativa os experimentos em relação à montagem tradicional, como a falta de vedação entre o alto-falante e o tubo e o perfil do sinal que não corresponde ao de uma onda estacionária quando o microfone está fixo ao êmbolo. Além de permitir uma correta interpretação do fenômeno, a utilização de um sistema automatizado para aquisição do sinal permitiu a observação de resultados experimentais que normalmente não são discutidos quando este tipo de experimento é realizado.

Despite rapid advances in both the early detection and treatment of cancer, the mortality from this disease remains high, which justifies the development of new products that are more selective and effective and have fewer side effects. Accordingly, a novel ester was synthesized that contains two pharmacophores with important biological activities: (I) 4-aminoantipyrine, which has anti-inflammatory and antioxidant effects, and (II) the pharmacophore 1,4-dioxo-butenyl, which has cytotoxic activity. When administered alone, this compound is non-genotoxic, and it does not cause an increasing in splenic phagocytosis. Nevertheless, it can induce cell death. When administered in combination with commercial chemotherapeutic agents, such as doxorubicin, cisplatin, and cyclophosphamide, the ester shows antigenotoxic activity and decreases phagocytosis and reduces the potential to cause cell death. These results indicate that the compound should not be used in combination with chemotherapeutic agents that exert their effect through DNA damage, an important feature of antitumor drugs.