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A protected pyruvate equivalent is described that allows arylation and arylation/alkylation reactions to be performed at the methyl group. Utilization of the OBO derivative of the pyruvate ester allowed the application of palladium catalyzed arylation reactions together with subsequent alkylation, under basic conditions. Moreover, the OBO protecting group could be easily removed in one step to provide access to a wide range of substituted pyruvate derivatives. [ABSTRACT FROM AUTHOR]

Three tobacco types (Burley, Flue Cured, and Oriental) and eight cigarette brands were unequivocally identified using an electronic nose formed by only three sensors based on a single novel conducting polymer ( PF-BTB ) doped with different porphyrins ( H 2 TPP , H 2 TPFP , and H 2 BTBOP ). The synthesis and characterization of the polymer are also discussed. Small changes in the porphyrin structure caused significant changes in the electrical conductance response patterns of the sensors upon exposure to complex chemical matrixes, representing a novel approach for tuning the selectivity of chemiresistive sensors for e-nose application. This e-nose is fast, cheap, reliable, can be easily operated, and could be a valuable tool for border agents fighting cigarette smuggling around the world, helping them prevent losses of millions in tax revenues and sales., Competing Interests: The authors declare no competing financial interest.

A protected pyruvate equivalent is described that allows arylation and arylation/alkylation reactions to be performed at the methyl group. Utilization of the OBO derivative of the pyruvate ester allowed the application of palladium catalyzed arylation reactions together with subsequent alkylation, under basic conditions. Moreover, the OBO protecting group could be easily removed in one step to provide access to a wide range of substituted pyruvate derivatives.

Synthesis of substituted β-carbolines was accomplished by utilizing the catalytic enolate arylation reaction of ketones in conjunction with several 3-bromoindole derivatives. Quenching of the arylation reaction in situ with an electrophile allowed ready incorporation of functionality at the carboline C-4 position in an efficient one-pot protocol.

The present work describes a solid-phase microextraction (SPME) gas chromatography-tandem mass spectrometry (MS/MS) method to quantify 24 pesticides in fortified white wine and fortified red wine. In this study "fortified wine" refers to a wine in which fermentation is arrested before completion by alcohol distillate addition, allowing sugar and alcoholic contents to be higher (around 80-100 g/L total sugars and 19-22% alcohol strength (v/v)). The analytical method showed good linearity, presenting correlation coefficients (R(2)) ≥ 0.989 for all compounds. Limits of detection (LOD) and quantitation (LOQ) in the ranges of 0.05-72.35 and 0.16-219.23 μg/L, respectively, were obtained. LOQs are below the maximum residue levels (MRL) set by European Regulation for grapes. The proposed method was applied to 17 commercial fortified wines. The analyzed pesticides were not detected in the wines tested.