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Mycetoma is currently considered as a neglected tropical disease. The incidence of mycetoma is unknown but most of the worldwide cases are present in the "mycetoma belt" including countries like Mexico, India, Senegal, and others. The treatment of mycetoma depends on the etiological agent responsible for the case. Treatment success reaches 60 to 90%; however, common treatment has been reported to be ineffective in some cases, due in part to resistance to the prescribed antibiotics. Therefore, it is necessary to develop new therapeutic options. In the past two decades, quinoxaline derivatives have shown relevance as antibacterial agents. Therefore, in this work, esters of quinoxaline 1,4-di-N-oxide derivatives were evaluated in vitro against the reference strain CECT-3052 from N. brasiliensis, six clinical isolates, and macrophages J774A.1 to determine their cytotoxicity and security index. Additionally, nine reference drugs were evaluated as controls. The results show that nine esters of quinoxaline 1,4-di-N-oxide derivatives had a minimum inhibitory concentration (MIC) < 1 µg/mL against the reference strain and four of them (N-05, N-09, N-11, and N-13) had an MIC < 1 µg/mL against the clinical isolates. Therefore, the scaffold quinoxaline 1,4-di-N-oxide could be used to develop new and more potent antinocardial agents. [ABSTRACT FROM AUTHOR]

This article discusses a new method for synthesizing homoallylic diene halides, which are important compounds used in the preparation of the taxane A-ring system. Taxol, a compound with anticancer properties, has been synthesized using various methods, including a type II intramolecular Diels-Alder reaction. The authors of this article report a new synthesis method for homoallylic halides, which are important precursors for the taxane ring system. The synthesis of these compounds was achieved using readily available and inexpensive starting materials, and the reactions are potentially scalable for large-scale production. The article provides technical information about the synthesis and characterization of various chemical compounds, including data such as nuclear magnetic resonance (NMR) spectra, mass spectrometry (MS) results, and experimental procedures. The authors acknowledge Prof. Joaquín Tamariz for HRMS analysis, and supporting information for the article is available online. [Extracted from the article]

The synthesis of the cyclic, naturally occurring amino acid baikiain from glycine and cis‐1,4‐butenediol is reported. The key step of the synthesis is an enantioselective phase transfer catalyzed allylation of the benzophenone imine of glycine t‐butyl ester, catalyzed by a cinchonidine quaternary ammonium salt, which provided the allylated glycine in 82% yield and 80% e.e. Further deprotection and hydrolysis of the Schiff base followed by an intramolecular Mitsunobu ring closure reaction yielded the corresponding piperidine ring system in 77% yield, which by hydrolysis yielded baikiain hydrochloride in 36% overall yield. Hydrogenation of the double bond could provide access to (S)‐pipecolic acid, which is also an important chiral synthon. [ABSTRACT FROM AUTHOR]

In recent years there has been a growing concern about environmental pollution linked to the generation of agroindustrial waste. The wine industry generates approximately 8.49 million tons of grape pomace per year worldwide; this residue can be used to obtain compounds with biological activity. Grape pomace is a source of anthocyanins, pigments that have antioxidant properties and help prevent cardiovascular disease. The development of sustainable extraction, purification and identification techniques constitutes an important step in adding value to this waste. Therefore, the present research has focused on presenting a review of works carried out in the last years. [ABSTRACT FROM AUTHOR]

An efficient, general synthetic protocol for the synthesis of the biologically active benzofurans ailanthoidol, egonol and homoegonol was developed. The key starting material, eugenol, is a naturally occurring and abundant precursor. The protocol, involving sequential acylation and intramolecular Wittig reaction, provides a convenient method for building the benzofuran moiety in good yield. [ABSTRACT FROM AUTHOR]

Physicochemical properties of a blend of 10% Aloe vera gel with 5% pitaya juice subjected to UV-C doses of 16.5, 27.7, and 40 mJ/cm 2 were evaluated at pH 3.5 and 5.5. Unprocessed treatments were used as the control. The a * color parameter decreased and luminosity increased at pH 3.5. The decrease in the reddish color was consistent with the decrease in total betalains content and stabilized at pH 5.5. The NMR analyses of UV-C treatments showed changes in betalains signal patterns. Polyphenolics content was significantly reduced in the UV-C treatments at pH 5.5. UV-C processing decreased the antioxidant activity 1.25 times compared to unprocessed treatments. Total sugar content was reduced as the UV-C dose increased. Doses above 16.5 mJ/cm 2 resulted in a higher simple sugar content at a pH 3.5. The UV-C continuous flow technology can be applied to stabilize betalains in Aloe vera -pitaya blends at a UV-C dose of 16.5 mJ/cm 2 and pH 5.5.