β-lactam antibiotics epitope mapping with STD NMR spectroscopy: A study of drug-human serum albumin interaction

Molecular recognition events are key issues in many biological processes. STD NMR (saturation transfer difference nuclear magnetic resonance spectroscopy) is one of the techniques used to understand such biological interactions. Herein, we have investigated the interactions of four β-lactam antibiotics belonging to two classes (cephalosporins and penicillins) with human serum albumin (HSA) by 1H STD NMR revealing that the interaction between the aromatic moiety and HSA is responsible for the binding efficiency. Thus, the structural differences from the five to six-membered thio ring in penicillins and cephalosporins do not seem to influence antibiotic-albumin interactions. © 2012 Sociedade Brasileira de Química.

Experimental NMR and MS study of benzoylguanidines. Investigation of E/Z isomerism

Molecules containing the guanidinic nuclei possess several pharmacological applications, and knowing the preferred isomers of a potential drug is important to understand the way it operates pharmacologically. Benzoylguanidines were synthesized in satisfactory to good yields and characterized by NMR, Electrospray Ionization Mass Spectrometry (ESI-MS) and Fourrier Transform InfraRed Spectroscopy techniques (FTIR). E/Z isomerism of the guanidines was studied and confirmed by NMR analysis in solution (1H-13C Heteronuclear Single Quantum Coherence (HSQC) and Heteronuclear Multiple-Bond Correlation (HMBC), 1H-15N HMBC, 1H- 1H Correlation Spectroscopy (COSY) and Nuclear Overhauser Effect Spectroscopy (NOESY) experiments) at low temperatures. Compounds with p-Cl and p-Br aniline moiety exist mainly as Z isomer with a small proportion of E isomer, whereas compounds with p-NO2 moiety showed a decrease in proportion of isomer Z. The results are important for the application of these molecules as enzymatic inhibitors. Copyright © 2013 John Wiley & Sons, Ltd.

Characterization of flavonoids and phenolic acids in Myrcia bella cambess. Using FIA-ESI-IT-MSn and HPLC-PAD-ESI-IT-MS combined with NMR

The leaves of Myrcia DC. ex Guill species are used in traditional medicine and are also exploited commercially as herbal drugs for the treatment of diabetes mellitus. The present work aimed to assess the qualitative and quantitative profiles of M. bella hydroalcoholic extract, due to these uses, since the existing legislation in Brazil determines that a standard method must be developed in order to be used for quality control of raw plant materials. The current study identified eleven known flavonoid-O-glycosides and six acylated flavonoid derivatives of myricetin and quercetin, together with two kaempferol glycosides and phenolic acids such as caffeic acid, ethil galate, gallic acid and quinic acid. In total, 24 constituents were characterized, by means of extensive preparative chromatographic analyses, along with MS and NMR techniques. An HPLC-PAD-ESI-ITMS and FIA-ESI-IT-MSn method were developed for rapid identification of acylated flavonoids, flavonoid-O- glycosides derivatives of myricetin and quercetin and phenolic acids in the hydroalcoholic M. bella leaves extract. The FIA-ESI-IT-MS techinique is a powerful tool for direct and rapid identification of the constituents after isolation and NMR characterization. Thus, it could be used as an initial method for identification of authentic samples concerning quality control of Myrcia spp extracts. © 2013 by the authors.

Solução do problema de corte bidimensional de peças retângulares tipo não-guilhotinado usando simulated annealing

Pós-graduação em Engenharia Elétrica - FEIS

Estudo de transições durante o processo de desenovelamento térmico da RNase A por meio da calorimetria (DSC) e espectroscopia de correlação bidimensional no infravermelho médio (2D-IR)

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Estudo do desenovelamento da papaína via espectroscopias de fluorecência e correlação bidimensional no infravermelho

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Uso do sistema de cultivo bidimensional e tridimensional para diferenciação de células-tronco espermatogoniais e indução da espermatogênese in vitro em murinos

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Propriedades magnéticas do modelo de Ising bidimensional em uma rede bipartida de spins 1/2 e 1: um estudo de ferrimagnetismo com vacâncias

Pós-graduação em Ciência e Tecnologia de Materiais - FC

Estudo de percolação de clusters de Monte Carlo para o modelo de Ising bidimensional

Pós-graduação em Física - IFT

Contribuições para o problema de corte de estoque bidimensional na indústria moveleira

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Propostas de solução para o problema de corte de estoque bidimensional de uma fábrica de móveis de pequeno porte

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Desenvolvimento de um sistema bidimensional de monitoração da saída de nadadores

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Análise da influência dos sistemas de retenção para overdentures implanto-retidas e da espessura e resiliência da fibromucosa na distribuição interna das tensões, através do método de elementos finitos bidimensional

Pós-graduação em Odontologia - FOA

Potencialidades biológicas e aspectos estruturais de compostos contendo paládio(II) e isonicotinamida

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Compostos fenólicos de Paepalanthus geniculatus (Eriocaulaceae)

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)