Anacardic acid (AA) is a bioactive phytochemical found in the nutshell of Anacardium occidentale, a tropical plant originally from Brazil. In this work, cross-linked anacardic acid nanocapsules (NC) were obtained by interfacial polymerization carried out using the inverse miniemulsion technique with 2,4-toluene diisocyanate (TDI). For this purpose, a functionalized monomer from AA was synthesized for formation of lipase-cleavable ester linkages by coupling of amino acids. The synthesis was planned so that when these ester linkages get exposed to an enzyme, they are broken down and released AA. Furthermore, the N-termini of the coupled amino compounds were used as sites for the polyaddition with TDI at the droplet interface in the inverse miniemulsion. The permeability of the shell was studied on the fluorescent dye, sulforhodamine 101 (SR101), using fuorescence spectroscopy After redispersion in water, the enzymatic cleavage of NC and the release of the SR101 were both monitored in real time. The released AA was proven to be active in vitro against Bacillus subtilis colonies in the bacterial tests. The results indicate that the use of NC is a promising strategy, which can make feasible the application of AA for therapeutic purposes and as nanocarriers for the delivery of active components.

Poly(2-(dimethylamino)ethylmethacrylate-b-methymethacrylate) (PDMAEMA-b-PMMA) poly(2-(dimethylamino)ethylmethacrylate-b-vinylcaprolactam-b-(2-(dimethylamino)ethyl methacrylate) (PDMAEMA-b-PVCL-b-PDMAEMA) and poly(vinylcaprolactam-b-(2-(dimethylamino)ethylmethacrylate-b-vinylcaprolactam) (PVCL-b-PDMAEMA-b-PVCL) block copolymers were obtained by reversible addition-fragmentation chain transfer (RAFT) polymerization, and the effect of the solution pH on the particle size was investigated. In the case of PDMAEMA-b-PMMA, PDMAEMA was first synthesized using 2-cyanoprop-2-yl dithiobenzoate (CPDB) as a chain transfer agent (CTA), which was subsequently used for the RAFT polymerization of MMA. The triblock copolymers were obtained using PDMAEMA or PVCL as macro-CTAs prepared using dibenzyl trithiocarbonate (DBTTC) as a bifunctional RAFT agent. The structure and formation of the copolymers was confirmed through ¹H NMR and SEC analysis. The particle size varied considerably depending on the pH of the aqueous solutions of copolymers indicating that these materials could be potential candidates for biomedical applications.

Este artigo utiliza simulações para estudar o processo de polimerização radicalar via transferência de átomo por meio da análise do comportamento das espécies químicas (polímeros "vivos", "dormentes" e "mortos"). Para isso, um modelo matemático foi desenvolvido usando o método dos momentos, e os dados experimentais da polimerização de estireno, obtidos da literatura, foram utilizados para validá-lo. A partir disto, foram obtidos perfis de concentração destas espécies, que foram posteriormente usados para obter as propriedades médias dos polímeros (Mn e IPD). As propriedades foram avaliadas em diferentes valores da costante deequilíbrio (Keq) e verificou-se que os valores na ordem de 10-7 e 10-9 proporcionam o melhor controle na estrutura dos polímeros. Esta pesquisa é, por isto, um ponto de partida para a escolha ideal do sistema catalítico, ligantes e iniciadores. Além disso, a técnica de modelagem apresentou-se como uma ferramenta de fácil implementação e bastante eficiente na análise do processo ATRP.

This article uses simulations to study the atom transfer radical polymerization by analyzing the behavior of the chemical species ("living", "dormant" and "dead" polymers). For this, a mathematical model has been developed using the method of moments, and experimental data from styrene polymerization, obtained from literature, were used to validate the model. From this point, the concentration profiles of all species were obtained, and later on, they were used to obtain the average properties of polymers (Mn and PDI). The properties were evaluated at different values of equilibrium constant (Keq) and it was found that values around 10-7 and 10-9 provide a better control in the structure of polymers. Therefore, this study is a starting point for selecting the optimal catalytic system, binders and initiators. In addition, the modeling technique presented as a useful tool, being very effective on the analysis of ATRP processes.

No presente trabalho, utilizou-se a calorimetria diferencial exploratória (DSC) para investigar a cinética da reação de cura de resinas epóxi produzidas a partir da reação do óleo de soja epoxidado (ESO), com os anidridos dodecenilsuccínico (DDS), maleico (MAL), ftálico (FTA), succínico (SUC) e hexahidroftálico (CH), atuando como agentes de cura, e na presença de aminas terciárias como a trietilamina (TEA), a N,N'-dimetilanilina (ARO) e a 1,4- diazobiciclo [2,2,2] octano (DABCO), atuando como catalisadores. A taxa de aquecimento, a natureza química e a estrutura do anidrido e das aminas influenciaram a reação de cura. Os métodos dinâmicos de Kissinger, Ozawa e de Barrett foram utilizados para calcular a energia de ativação dos sistemas onde se variou o anidrido. Observou-se que os anidridos mais reativos foram o DDS e maleico que apresentaram os menores valores de energias de ativação. No estudo da influência do catalisador, utilizou-se o método de Barrett para determinar as energias de ativação das reações com as diferentes aminas. A amina cicloaliafática (DABCO) foi a mais reativa obtendo-se o menor valor de energia de ativação (Ea = 51 kJ.mol-1) e fator pré-exponencial (ln A0 = 9 s-1).

In the present work, differential scanning calorimetry (DSC) was used to investigate the curing reaction kinetics of epoxy resins produced from reaction of epoxidized soybean oil (ESO) with cyclic anhydrides dodecenylsuccinic (DDS), maleic (MAL), phthalic (PA), succinic (SUC) and hexahydrophthalic (CH), in the presence of tertiary amines such as triethylamine (TEA), N,N-dimethylaniline (ARO) and 1,4-diazabicyclo [2,2,2] octane (DABCO). The heating rate, the nature and structure of anhydrides and amines were found to affect the curing reaction. The dynamic methods of Kissinger, Ozawa and Barrett were used to calculate the activation energy of the reactions where different anhydrides were used. DDS and maleic anhydrides were more reactive than the others. In studying the influence from the catalyst, we used the Barret's method to determine the activation energy of the reactions. The 1,4-diazabicyclo [2,2,2] octane amine (DABCO) was the most reactive, showing the lowest activation energy (Ea= 51 kJ.mol-1) and pre-exponential factor (ln A0 = 9 s-1).

Nesse trabalho estudou-se a reação de ciclodesidratação entre antranilonitrila e várias cetonas na presença de diferentes ácidos de Lewis não reportados na literatura, para a obtenção de 9-amino-1,2,3,4-tetrahidroacridinas. As reações de ciclodesidratação foram realizadas em condições térmicas empregando-se diferentes solventes e também na ausência de solvente, seguidas de hidrólise alcalina, levando à obtenção dos produtos em bons a excelentes rendimentos após isolamento.

The scope of Lewis acid-promoted cyclodehydratation reactions between anthranilonitrile and several ketones, to afford tacrine and its derivatives, was expanded to include the use of various metal chloride salts not reported in the literature. The ability of the Lewis acids to effectively promote the cyclodehydratation between anthranilonitrile and cyclohexanone as the ketone was found to be the following order: InCl3 > AlCl3 ~ BF3.Et2O > FeCl3 > BiCl3 ~ SbCl3 ~ SnCl2.2H2O. The reactions were performed under both solvent and solvent-free conditions in good to excellent yields. Other Lewis acids screened, such as RuCl3, CeCl3, NiCl2, CoCl2.2H2O and CsCl were not effective.

Este trabalho descreve a preparação enantiosseletiva da (R)-(+)-isocarvona, (S)-(-)-5-isopropenilcicloex-2-enona e (S)-(-)-3-isopropenilcicloexanona, a partir do (S)-(-)-perilaldeído. Estes compostos podem ser usados como blocos de construção importantes para a síntese orgânica.

This work describes the enantioselective preparation of (R)-(+)-isocarvone, (S)-(-)-5-isopropenylcyclohex-2-enone and (S)-(-)-3-isopropenylcyclohexanone starting from (S)-(-)-perillaldehyde. These compounds hold the prospect of serving as useful chiral building blocks or intermediates in organic synthesis.

Tricloreto de índio na presença de hipoclorito de sódio promove a cloração alílica de olefinas terminais em meio bifásico (diclorometano/água) com bons rendimentos. Para estabelecer um procedimento geral, escolheu-se a carvona como composto modelo e otimizou-se a estequiometria, temperatura, e tempo de conversão para o respectivo cloreto alílico. Tratando-se beta-pineno com tricloreto de índio/hipoclorito de sódio obteve-se seletivamente o cloreto perílico, um precursor importante para a obtenção de derivados de limoneno oxigenados no carbono C-7.

Indium trichloride promotes the chlorination of terminal olefins in the presence of sodium hypochlorite with good results. Carvone was chosen as a model compound to examine some of the general features of this reaction, such as stoichiometry, temperature, reaction time and product conversion. Treatment of beta-pinene with sodium hypochlorite in the presence of indium trichloride resulted in a facile rearrangement to selectively yield perillyl chloride, which is an important precursor for C-7 oxygenated limonenes.

New types of polyurethanes were prepared by reacting diisocyanates and formiated soy polyols with different OH functionalities. Thermal properties and degradation kinetics were investigated by TGA. All prepared PU's showed at least two-weight loss steps, the first one, around 210 °C. Thermal stability of these PUs depends strongly on urethane groups per unit volume and an increase in the weight loss was observed as a result of the increased amount of urethane groups. Degradation kinetics behavior of the soy-based polyurethanes was investigated according to the Flynn method. Different average activation energy values were obtained from isothermal and isoconversional curves, 140.6 KJ/mol and 62.8 KJ/mol, respectively, indicating the complexity of the PUs degradation process.