Essential oil (EO) of the leaves of Eugenia uniflora L. (Brazilian cherry tree) was evaluated for its antioxidant, antibacterial and antifungal properties. The acute toxicity of the EO administered by oral route was also evaluated in mice. The EO exhibited antioxidant activity in the DPPH, ABTS and FRAP assays and reduced lipid peroxidation in the kidney of mice. The EO also showed antimicrobial activity against two important pathogenic bacteria, Staphylococcus aureus and Listeria monocytogenes, and against two fungi of the Candida species, C. lipolytica and C. guilliermondii. Acute administration of the EO by the oral route did not cause lethality or toxicological effects in mice. These findings suggest that the EO of the leaves of E. uniflora may have the potential for use in the pharmaceutical industry.

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A significant number of important acyl-transfer reactions, such as direct acylation, ortho acylation, heteroatom acylation, and a diversity of cyclization reactions using the title compound as a key starting material, have been described in recent years. Just like a sleeping beauty, α-oxocarboxylic acids were awakened from a 17-year sleep to become important reagents in classical and new acylation reactions. The greener characteristic of the coproduct formed in reactions using α-keto acid (only CO 2 ), together with its versatility as a building block in catalytic organic synthesis, accredit it as a candidate to green acylating agent, an alternative to acyl chloride, and other acyl-transfer reagents. This review presents the impressive breakthroughs achieved mainly in the past decade in the development of new catalytic reactions for the formation of C−C, C−N, and C−S bonds using α-keto acids. CONTENTS 1. Introduction 7113 2. Classical Methods and Recent Advances in the Synthesis of α-Keto Acids 7115 2.1. Physical Properties of α-Keto Acids 7119 3. α-Keto Acids in Acylation Reactions 7119 3.1.

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This review is dedicated to the memory of Prof. Nicola Petragnani, a pionner in the chemistry of selenium and tellurium in Brazil, who passed away on December 5, 2015.Organochalcogen compounds (containing S, Se and Te) are interesting either for use as an intermediate in the synthesis of complex molecules or for the exploitation of their biological properties. The growing in the number of papers on the synthesis and application of organochalcogen compounds has been accompanied by a concern about how they are prepared. Here, we provide a comprehensive and updated review on re-cent synthetic methods available for their synthesis using alternative solvents or solvent-free conditions and non-classical energy sources (microwaves irradiation, sonochemistry and mechanochemistry). Organized in fourteen sections, this review brings the more than one hundred alternative methods described so far to access organic compounds containing selenium, tellurium and sulfur.[a] Prof.

As imple and rapid methodf or the selective synthesis of 3-(organylselanyl)-1 H-indoles and3 -(organylselanyl)imidazo[1,2-a]pyridines catalyzed by CuI/SeO 2 under ultrasound irradiation was developed. This protocol employs adiverse range of 1 H-indoles or imidazo[1,2-a]pyridines and diorganyl diselenides to afford the corresponding products selectively in good to excellent yields. Moreover,t he antioxidant activity of these compounds was evaluated by using aw ider ange of in vitro assays,s uch as 2-azinobis-3-ethylbenzothiazoline-6-sulfonic acid (ABTS), 2,2-diphenyl-1picrylhydrazyl (DPPH) radical, ferric ion reducing antioxidant power (FRAP), and inhibition of reactive speciesf ormation in mice cortex. The bioassays revealed thatb oth classes of the newly synthesized organoselenium compounds present antioxidanta ctivity,w ith emphasis on the 3-(organylselanyl)-1 Hindoles.T his pharmacological activity opens aw ide range of biological applications where the reduction of oxidative stress is essential.[a] B. Results and DiscussionAc omparatives tudy on the use of microwaves, US, and conventional heating in the copper-catalyzed selenylation of indoles in DMSO was recently reported by us. [18b] In this reaction, Figure 1. 3-Arylselanylindoles A and B and 3-thioimidazo[1,2-a]pyridines C and D with similar effects to Combretastatin A-4a nd Enviroxime.Scheme1.Generalscheme of the present work.

Ultrasonic (US) irradiation was successfully used as an alternative energy source to prepare 3-selanylindoles through the direct selanylation of indoles with diorganyl diselenides using CuI (20 mol%) as catalyst and DMSO as the solvent. By using this US-promoted reaction, eleven 3-organylselanylindoles were prepared selectively and in good yields. A comparative study between the reactions under conventional heating, microwave and ultrasound irradiations was performed, and it was observed advantage in using US over the other heating systems.