This paper reports a comparative study of the chemoselectivity and yields of the synthesis of N-alkyl-4-(trihalomethyl)-1H-pyrimidin-2-ones carried out by the cyclocondensation of 4-alkoxy-1,1,1-trihalo-3-alken-2-ones (enones) with methyland allylureas with the N-alkylation of 4-(trihalomethyl)-1H-pyrimidin-2-ones with methyl iodide and allyl bromide. To determine the chemoselectivity of the products obtained, all compounds were fully analyzed by 1 H and 13 C NMR and 2D HMBC spectroscopy. This study has demonstrated that the

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The bark tea of Ceiba speciosa, a tropical tree of the Malvaceae family, is used in the Northwestern Region of Rio Grande do Sul state, Brazil, to reduce blood cholesterol levels. However, there are no scientific data on the efficacy and safety of this plant. The aim of the present study was to evaluate the in vitro antioxidant and toxic potential of bark extracts of C. speciosa. We performed a preliminary phytochemical analysis by high-performance liquid chromatography-diode array detection (HPLC-DAD) and evaluated the oxidative damage to proteins and lipids, the radical scavenging effect, and genotoxicity of the lyophilized aqueous extract (LAECs) and the precipitate obtained from the raw ethanol extract (Cs1). The phytochemical profile demonstrated the presence of phenolic and flavonoid compounds. The LAECs and Cs1 prevented damage to lipids and proteins at concentrations of 50 and 10 µg/mL. They also showed a scavenging effect on 2,2-diphenyl-1-pricril-hydrazyl (DPPH) radicals in a concentration-dependent manner. Furthermore, no genotoxic effect was observed at concentrations of 10, 5 and 2 µg/mL in the Comet assay. The present study is the first evaluation regarding the characterization of C. speciosa and its safety, and the results demonstrate its antioxidant potential and suggest that its therapeutic use may be relatively safe.Uniterms: Ceiba speciose/phytochemistry. Ceiba speciose/antioxidant activity. Phenolic content. Comet assay. DPPH scavenging capacity. Natural medicine. Safety.

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A convenient method for the synthesis of a series of 4-trichloromethyl-pyrimidin-2-ylamines from the reaction of 4-trichloromethyl-2-chloropyrimidine and ammonium hydroxide, primary-and secondary-amines, and guanidine hydrochloride, is reported. This reactions was also extended to obtain 4-trichloromethyl-2-alkoxy-pyrimidines.Among the pyrimidine derivatives the number of aminopyrimidines has only been exceeded by hydroxypyrimidines. 1 Aminopyrimidines have attracted much attention due to important biological activities that many 2855