Formação inicial de professores de química: o processo de construção do currículo de química, em um curso de Licenciat

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Complete ¹H and 13C NMR structural assignments for a group of four goyazensolide-type furanoheliangolides

Four goyazensolide-type sesquiterpene lactones - lychnofolide, centratherin, goyazensolide and goyazensolide acetate - were thoroughly studied by NMR experimental techniques. ¹H NMR, 13C NMR {¹H}, COSY, HMQC, HMBC, J-res. and NOE experiments were performed to provide the needed structural information. Complete and unequivocal assignment, including the determination of all multiplicities, was obtained for each structure and the data collections are presented in tables

Reduction and Preparation of a Phthalimide Derivative from a Furo-heliangolide

Goyazensolide, a biologically active natural product classified as a furoheliangolide, was transformed in a phthalimide derivative that showed an enhanced biological activity against Tripanosoma cruzi. The complex natural product was also reduced with high stereoselectivity by hydrogen/Wilkinson’s catalyst; an epimer of this product was obtained in the reduction with hydrogen/Pd-C

Reduction and Preparation of a Phthalimide Derivative from a Furo-heliangolide

Goyazensolide, a biologically active natural product classified as a furoheliangolide, was transformed in a phthalimide derivative that showed an enhanced biological activity against Tripanosoma cruzi. The complex natural product was also reduced with high stereoselectivity by hydrogen/Wilkinson’s catalyst; an epimer of this product was obtained in the reduction with hydrogen/Pd-C

Simulação de desdobramentos complexos de espectros de RMN de ¹H Simulation of complex splittings of ¹H NMR spectra

<abstract language="eng">Complex ¹H NMR spectra multiplets that cannot be easily understood by simple inspection are rather frequent in the daily work of the organic chemistry analyst. The multiple and excellent new techniques available from modern instruments usually provide satisfactory solutions, but there are still many cases where a simulation is necessary, at least to obtain a final confirmation. It is extremely convincing to see that a graph, obtained by calculations with chemical-shift and coupling-constant values only, can be virtually identical to the experimental spectrum. This paper describes a computer program to make such calculations. The program is free and can be downloaded from <A HREF="http://artemis.ffclrp.usp.br/NMR.htm">http://artemis.ffclrp.usp.br/NMR.htm</A> (click on SimEsp_NMR_Compil.zip). All routines are also available and may be used without any restrictions. The paper includes a fairly detailed discussion about how the calculations are made

Detailed H-1 and C-13 NMR structural assignment and relative stereochemistry determination for three new and one known semi-synthetic sesquiterpene lactones

In this work is described a complete H-1 and C-13 NMR analysis for a group of four sesquiterpene lactones, three previously unknown. The unequivocal assignments were achieved by H-1 NMR, C-13{H-1} NMR, gCOSY. gHMQC, gHMBC and NOESY experiments and no ambiguities were left behind. All hydrogen coupling constants were measured, clarifying all hydrogen signals multiplicities. (C) 2011 Elsevier B.V. All rights reserved.FAPESPFAPESPCAPESCAPESCNPqCNP

Solvent Effect in Reactions Using Stryker's Reagent

The solvent has a significant influence in the rate of reactions promoted by Stryker's reagent The reactions performed in THF were, in most cases, faster than in toluene.FAPESPFAPESPCNPqCNPqCAPESCAPE