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NMR spectroscopy is traditionally taught to students during Organic Chemistry as a tool used for the determination of structures after synthesis. However, modern NMR spectroscopy has many important applications beyond structure elucidation, including molecular profiling of complex mixtures as biofluids and food samples. In this experiment, students collect a series of nonselective and selective 1D NMR spectra of natural and supermarket fruit juices and are asked to identify and quantify the sugars present. For the quantitative analysis of the juices, the students must use the ERETIC2 (electronic reference to access in vivo concentrations 2) method embedded in the NMR software.

A novel lipoformulation was developed by encapsulating cationic (S^C)-cyclometallated gold(III) complex [Au(dppta)(N2Py-PZ-dtc)]+ (AuPyPZ) in liposomes. The liposomal form of compound AuPyPZ has a bactericidal action similar to that of the free drug without any appreciable effect on the viability of mammalian cells. Furthermore, the nanoformulation reduces metalloantibiotic-induced inhibition of hERG and the inhibition of cytochromes, significantly decreasing the potential liabilities of the metallodrug. The obtained metalloantibiotic liposomal formulation shows high stability and suitable properties for drug delivery, representing an effective strategy to fight against drug-resistant bacteria. [ABSTRACT FROM AUTHOR]

A series of cyclometallated gold(III) complexes 21–27 of general formula [Au(dppta)(azdtc)Cl] (dppta = N,N-diisopropyl-P,P-diphenylphosphinothioic amide-κ2C,S; azdtc = azol(in)ium-2-dithiocarboxylate-κ1S) were prepared and characterized by spectroscopic and diffractometric techniques. Treatment of [Au(dppta)(azdtc)Cl] complexes with methanol led to their quantitative transformation into a novel family of (C^S, S^S)-cyclometallated gold(III) complexes of general formula [Au(dppta)(azmtd)] (azmdt = azol(in)ium-2-(methoxy)methanedithiol-κ2S,S) 28–34. All the [Au(dppta)(azdtc)Cl] complexes 21–27 catalyzed the alkylation of indoles, whereas [Au(dppta)(azmtd)] complexes 28–34 were inactive. Among the synthesized derivatives, complex 22 displayed the highest catalytic activity, leading to a series of functionalized indoles in excellent yields. [ABSTRACT FROM AUTHOR]

Azolium-2-thiocarboxylate zwitterion ligands have emerged as a promising class of compounds in the field of coordination chemistry due to their unique structural features and versatile applications. These ligands are characterized by a positively charged azolium ring and a negatively charged thiocarboxylate moiety, making them capable of forming stable coordination complexes with various metal ions. One of the key structural aspects that make these ligands attractive for coordination chemistry is their ability to adopt diverse coordination modes with metal centers. The nature of these ligands enables them to engage in both monodentate and bidentate coordination, resulting in the formation of chelated complexes with enhanced stability and controlled geometry or the formation of polynuclear structures. This versatility in coordination behavior allows for the design of tailored ligands with specific metal-binding preferences, enabling the creation of unique and finely tuned coordination architectures. The azolium-2-thiocarboxylate zwitterionic ligands offer a promising platform for the design of coordination complexes with diverse structural architectures. [ABSTRACT FROM AUTHOR]

Introduction: Antimicrobial resistance is a pressing global concern that has led to the search for new antibacterial agents with novel targets or non-traditional approaches. Recently, organogold compounds have emerged as a promising class of antibacterial agents. In this study, we present and characterize a (C^S)- cyclometallated Au(III) dithiocarbamate complex as a potential drug candidate. Methods and results: The Au(III) complex was found to be stable in the presence of effective biological reductants, and showed potent antibacterial and antibiofilm activity against a wide range of multidrug-resistant strains, particularly grampositive strains, and gram-negative strains when used in combination with a permeabilizing antibiotic. No resistant mutants were detected after exposing bacterial cultures to strong selective pressure, indicating that the complex may have a low propensity for resistance development. Mechanistic studies indicate that the Au(III) complex exerts its antibacterial activity through a multimodal mechanism of action. Ultrastructural membrane damage and rapid bacterial uptake suggest direct interactions with the bacterial membrane, while transcriptomic analysis identified altered pathways related to energy metabolism and membrane stability including enzymes of the TCA cycle and fatty acid biosynthesis. Enzymatic studies further revealed a strong reversible inhibition of the bacterial thioredoxin reductase. Importantly, the Au(III) complex demonstrated low cytotoxicity at therapeutic concentrations in mammalian cell lines, and showed no acute in vivo toxicity in mice at the doses tested, with no signs of organ toxicity. Discussion: Overall, these findings highlight the potential of the Au(III)- dithiocarbamate scaffold as a basis for developing novel antimicrobial agents, given its potent antibacterial activity, synergy, redox stability, inability to produce resistant mutants, low toxicity to mammalian cells both in vitro and in vivo, and non-conventional mechanism of action. [ABSTRACT FROM AUTHOR]

A new substrate‐controlled hydrogenation of flavanones to selectively obtain different hydrogenation products is herein reported. Thus, hydrogenation of flavanones bearing different electron‐donating and electron withdrawing substituents (Cl, Br, Me, OMe, OH) provided the corresponding 1,3‐diarylpropanes in excellent yields. This procedure offers a straightforward, simple, and cost‐effective method for the preparation of glycosylated 2′‐hydroxy‐1,3‐diarylpropanes derived from natural flavanones such as Naringin and Hesperedin. On the contrary, when the hydrogenation was performed over fluorinated flavanones, the corresponding flavans were selectively obtained in excellent yields. [ABSTRACT FROM AUTHOR]