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Fruits are widely used to obtain and study bioactive compounds. Among them, the tarumã (Vitex megapotamica) is still understudied. The extraction of bioactive compounds from the powdered pulp of the ripe fruit of the tarumã was studied from the selection of several variables of the extraction process through the experimental design Plackett–Burman: the pH, the solid:liquid ratio, agitation, and temperature in an extraction time of 3 h. The extracts obtained were evaluated for antioxidant activity by 2,2′‐azino‐bis‐(3‐ethylbenzothiazoline‐6‐sulfonic acid) (ABTS), 2,2‐diphenyl‐1‐picrylhydrazyl (DPPH), and for total phenolic compounds, as well as the presence of flavonoids, anthocyanins, carotenoids, and identification of bioactive compounds was assessed by high‐performance liquid chromatography (HPLC). Using the experimental design, the best extraction condition was defined with a pH of 5, solid:liquid ratio of 1:30, stirring at 100 rpm, with a temperature of 80°C, obtaining 104.21 mg Gallic Acid Equivalent (GAE) 100 g−1 for phenolic compounds total, 742.71 μmol Trolox g−1 for ABTS, and EC50 of 2884.98 mg L−1 for DPPH. From HPLC, the presence of fumaric acid, gallic acid, p‐coumaric acid, and caffeic acid in the extracts was detected. Regarding flavonoids, anthocyanins, and carotenoids, the values obtained were 6.38 mg ECG g−1, 1.67 mg ECG g−1, and 2.89 mg 100 g−1, respectively. The selection of extraction conditions allowed obtaining better levels of bioactive compounds in the powdered pulp of tarumã extract, even with the use of water as a solvent, to avoid the presence of chemical residues in the extract, with antioxidant potential and viability for application in food products. Practical applications: Recent research suggests a change in perspective regarding the consumption of healthier foods from plants and fruits that have important health properties. In this regard, tarumã (Vitex megapotamica) fruit has been standing out as a potential source of bioactive compounds with significant medicinal properties. The extracts obtained have a significant amount of phenolic compounds, as well as the presence of flavonoids, anthocyanins, and carotenoids, in which all of these have great potential bioactive activities. Thus, a good methodology of extraction and characterization of tarumã extract becomes a crucial part of any food, chemical, or pharmaceutical industry sector. In this regard, the present study with experimental design Plackett–Burman extraction is the way ahead due to high bioactive retention and the cost implications of the process. [ABSTRACT FROM AUTHOR]

Herein, we describe an efficient and selective Cu‐catalyzed C−H bond chalcogenation of the indolizine core, in the presence of DMSO and applying ultrasound irradiation as an alternative energy source. Under the optimal conditions, 3‐sulfanylindolizines (16 examples) were prepared in moderate to good yields starting from diorganyl disulfides and 2‐arylindolizines. When diphenyl diselenide was used, 1,3‐bis(selanyl) indolizines (4 examples) were exclusively obtained in very good yields. The use of ultrasound irradiation makes the reaction faster and more selective when compared to conventional heating. [ABSTRACT FROM AUTHOR]

Abstract: Herein, we report a greener protocol for the synthesis of 3‐Se/S‐indoles and imidazo[1,2‐a]pyridines through direct C(sp2)−H bond chalcogenation of heteroarenes with half molar equivalents of different dichalcogenides, using KIO3 as a non‐toxic, easy‐to‐handle catalyst and a stoichiometric amount of glycerol. The reaction features are high yields, based on atom economy, easy performance on gram‐scale, metal‐ and solvent‐free conditions as well as applicability to different types of N‐heteroarenes. [ABSTRACT FROM AUTHOR]

We describe herein a simple, fast and inexpensive protocol for the oxidative coupling of thiols employing a stoichiometric amount of DMSO and iodine as the catalyst. Various aromatic disulfides were obtained in good to excellent yields in short reaction times at room temperature, while aliphatic disulfides were achieved in good yields when the reactions were conducted under microwave irradiation. [ABSTRACT FROM AUTHOR]

Herein, we report the microwave-assisted synthesis of 1,3-diynes from terminal acetylenes, catalyzed by CuI and tetramethylethylenediamine, in the presence of air as the oxidant, at 100 °C for only 10 min under solvent-free conditions. This efficient methodology allowed the homocoupling of several terminal alkynes in moderate to excellent yields. Moreover, the same protocol was also applicable for the synthesis of some unsymmetrical 1,3-diynes through the cross-coupling reaction. [ABSTRACT FROM AUTHOR]

Herein, we describe a simple and efficient route to access aniline-derived diselenides and evaluate their antioxidant/GPx-mimetic properties. The diselenides were obtained in good yields via ipso-substitution/reduction from the readily available 2-nitroaromatic halides (Cl, Br, I). These diselenides present GPx-mimetic properties, showing better antioxidant activity than the standard GPx-mimetic compounds, ebselen and diphenyl diselenide. DFT analysis demonstrated that the electronic properties of the substituents determine the charge delocalization and the partial charge on selenium, which correlate with the catalytic performances. The amino group concurs in the stabilization of the selenolate intermediate through a hydrogen bond with the selenium. [ABSTRACT FROM AUTHOR]

One-pot modular synthesis of β-chalcogen amides via regioselective 2-oxazolines ring-opening reaction promoted by indium chalcogenolates under microwave irradiation. • New synthetic methodology allows quick access to β-chalcogen amides. • Simpler and greener experimental protocol for the 2-oxazoline ring-opening reaction. • Reaction time reduced from 24 h to 20 min using microwave irradiation. • Modular synthesis, easily accessible starting materials, high value-added products. We describe herein a microwave-assisted synthesis of β-chalcogen amides through the regioselective ring-opening reaction of 2-oxazolines promoted by bis(organoylchalcogeno)iodo indium(III) in situ generated. This protocol allows the preparation of structurally diverse β-chalcogen amides, with moderate to good yields, within a much shorter reaction time compared to conventional heating protocols. [ABSTRACT FROM AUTHOR]

• Benzothiazoles were efficiently prepared starting from disulfides and primary alcohols. • 2-Alkylbenzothiazoles were prepared from primary alcohols using DTBP as oxidant. • Bis(o -aminophenyl) disulfides were converted to 2-arylbenzothiazoles. • 2-Arylbenzothiazoles were prepared from benzylic alcohols in the presence of DTBP. A peroxide-mediated protocol for the synthesis of 2-substituted benzothiazoles was developed, starting from bis(o -aminophenyl) disulfides and primary alcohols. Eleven differently 2-substituted benzothiazoles were prepared in moderate to excellent yields using di- tert -butyl peroxide (DTBP) as an oxidant. [ABSTRACT FROM AUTHOR]

Abstract: Herein, we report a greener protocol for the synthesis of 3‐Se/S‐indoles and imidazo[1,2‐a]pyridines through direct C(sp2)−H bond chalcogenation of heteroarenes with half molar equivalents of different dichalcogenides, using KIO3 as a non‐toxic, easy‐to‐handle catalyst and a stoichiometric amount of glycerol. The reaction features are high yields, based on atom economy, easy performance on gram‐scale, metal‐ and solvent‐free conditions as well as applicability to different types of N‐heteroarenes. [ABSTRACT FROM AUTHOR]