Publications by authors named "Vera C M Duarte"

The increasing demand for solar energy has led researchers worldwide to develop new photovoltaic technologies. Among these, perovskite materials are one of the most promising candidates, with a performance evolution unparalleled in the photovoltaic field. However, this thin-film technology is not yet available at a commercial level, mainly due to upscaling issues.

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Different electron-rich dienophiles were combined with the imine obtained from 2,4-O-benzylidene-d-erythrose and p-anisidine furnishing enantiomerically pure tetrahydroquinolines, by inverse electron-demand [4π + 2π] cycloaddition. The imine was also reacted with 2-substituted electron-rich 1,3-butadienes giving the diastereomeric pure product, resulting from the normal electron demand cycloaddition. The facial selectivity of both processes is proposed on the basis of a 1,4-relationship between the hydroxyl group and the nitrogen atom in the chiral N-(p-methoxyphenyl)imine derivative.

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A range of novel pyridine 2,4,6-tricarbohydrazide derivatives (4a-4h) were synthesized and its biological inhibition towards α- and β-glucosidases was studied. Most of the compounds demonstrate to be active against α-glucosidase, and quite inactive/completely inactive against β-glucosidase. A number of compounds were found to be more active against α-glucosidase than the reference compound acarbose (IC50 38.

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1-N-Carboxamide 1-azafagomines and 5-epi-1-azafagomines were obtained from 1-azafagomine and 5-epi-1-azafagomine. The hydroxyl groups and the N-2 pyridazine position were protected prior to reaction with different isocyanates to form ureas. Protective groups were removed leading to the target compounds in 18-23% global yields.

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A new expeditious preparation of homochiral (-)-1-azafagomine and (+)-5-epi-1-azafagomine has been devised. Stoodley's diastereoselective cycloaddition of dienes bearing a 2,3,4,6-tetraacetyl glucosyl chiral auxiliary to 4-phenyl-1,2,4-triazole-3,5-dione was merged with Bols's protocol for functionalizing alkenes into molecules bearing a glucosyl framework. Homochiral (+)-5-epi-1-azafagomine was synthetized for the first time.

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