Chirality is an interesting property in molecules with a plethora of potential applications. In this line, due to their origin, most chiral natural compounds can be considered enantiopure, and many of these molecules include interesting functional groups that can be of interest in both coordination and organometallic chemistry to obtain chiral coordinated and/or organometallic compounds. And most importantly, these molecules may thus confer chiral properties into their metal complexes. Therefore, in this work, we show the use of kaurenoic (1) and beyerenoic (2) acids as efficient ligands to obtain the corresponding organometallic Ru(II) complexes by using [(η6-p-cymene)Ru(μ-Cl)Cl]2 as starting material by a simple procedure reacting the corresponding sodium salts of 1 and 2 (1a and 2a) with [(η6-p-cymene)Ru(μ-Cl)Cl]2 in an 2:1 M ratio to yield the corresponding (Sa)-[Ru(η6-p-cymene)(κ2-beyerenate)Cl] (3) and (Sa)-[Ru(η6-p-cymene)(κ2-kaurenate)Cl] (4) derivatives. Both complexes were fully characterized by common spectroscopic techniques and their structures unequivocally determined by single crystal X-ray diffraction analysis. In addition, the chirality of both organometallic compounds was analyzed by electronic circular dichroism techniques as well as by in silico methods. Antimicrobial assays were boarded demonstrating slight antifungal activity. The results not only confirm the conferring of chirality by the ligands to their organometallic derivatives but also open a window for their future potential applications as, for example, potential chiral catalysts or as metallodrugs in the battle against diseases of global concern as well optimistically inspiring the potential use of other natural products as ligands with a wide number of applications.

Metal-organic frameworks (MOFs) are widely used in the field of chromatographic separation due to their unique properties. A vapor diffusion method was used to synthesize the cyclodextrin MOF (CD-MOF) with D-histidine (D-His) as a chiral ligand (D-His-γ-CD-MOF), which was applied to capillary electrochromatography (CEC). D-His-γ-CD-MOF was characterized by X-ray diffractometer (XRD), transmission electron microscope (TEM), scanning electron microscope (SEM), Fourier transform infrared spectrometer (FT-IR), and thermogravimetric analyzer (TGA). This CEC system achieved baseline separation of three chiral drugs under optimal separation conditions. In addition, this CEC system was evaluated for repeatability using salbutamol as a model drug and the results showed that this system had good repeatability. Additionally, the chiral separation mechanism of the CEC system was discussed through adsorption kinetic experiments, adsorption isotherm experiments, and adsorption thermodynamic experiments.

Talazoparib is an oral inhibitor of the polyadenosine 5'-diphosphoribose polymerase enzymes used for the treatment of adults with deleterious or suspected deleterious germline BRCA-mutated, human epidermal growth factor receptor 2-negative, locally advanced, or metastatic breast cancer. A novel chiral HPLC method was proposed for the enantiomeric separation and quantification of talazoparib. Chiral separation was performed in a reversed-phase mode on a Chiralpak IC (4.6 × 250 mm, 5 μm) column using a simple mobile phase consisting of 0.2% perchloric acid in water:acetonitrile (60:40, v/v). A Box-Behnken design was used for the optimization of chromatographic parameters, and the enantiomeric separation was obtained within 12 min with a resolution value exceeding 7.7. The method was validated with respect to specificity, linearity, accuracy, precision, and robustness. The accuracy and precision of the method were satisfactory, with intraday and interday recovery values of 98%-102% and relative standard deviation values less than 2%. The method was used for the enantiomeric purity control of talazoparib in pharmaceutical formulations, which is crucial for patient safety and therapeutic efficacy.

Eganelisib (EGN, IPI-549), an investigational new drug, is a potent first-in-class PI3Kγ inhibitor with high selectivity compared to other class I PI3K isoforms, with one asymmetric center. Enantiomers have similar physicochemical properties but differ in their biological characteristics, like absorption, distribution, metabolism, and excretion. Hence, a suitable analytical approach is required to investigate the enantioselective behavior in ADME-Tox. In the current study, a sensitive, reliable, and precise chiral LC-MS/MS method has been developed for quantifying EGN enantiomers in rat plasma, in accordance with USFDA guidelines. Enantiomeric separation was achieved within 15 min on a Chiralpak-IK-3 (250 × 4.6 mm, 3 μm) immobilized polysaccharide column, containing 10 mM ammonium bicarbonate and a premixed mixture of acetonitrile and methanol (80:20 v/v) as the mobile phase in the ratio of 10:90 (v/v), with isocratic elution at a flow rate of 0.6 mL/min. Multiple reaction monitoring (MRM) mode was used to detect EGN and SOF in positive electrospray ionization (ESI) mode, characterized by their transitions at m/z 529.3→326.3, 161.1, and m/z 465.1→447.1, 270.2, 252.1. The method demonstrated a linear response in the range of 1-600 ng/mL for both enantiomers, with a lower limit of quantification of 1 ng/mL. The validated bioanalytical method was applied to evaluate the enantioselective pharmacokinetics of EGN enantiomers in rat plasma for the first time, utilizing a model-independent approach. The (R)-enantiomer showed relative fold differences in Cmax, t1/2, AUC0-t, and AUC0-∞ when compared to the (S)-enantiomer, indicating the enantioselective behavior of EGN enantiomers.

Two chiral Ru(II) complexes bearing a quinoline ring, Λ-[Ru(bpy)2(qip)]2+ (Λ-1) and Δ-[Ru(bpy)2(qip)]2+ (Δ-1, where bpy = 2,2'-bipyridine and qip = 2-(quinolin-3-yl)-1H-imidazo[4,5-f][1,10]phenanthroline), were prepared. Their interactions with triplex RNA were systematically investigated using ultraviolet-visible (UV-Vis) spectroscopy, luminescence spectroscopy, nucleic acid thermal denaturation experiments, and circular dichroism (CD) spectroscopy. The data from UV-Vis titrations support intercalation as the binding mode for both enantiomers with triplex RNA. Further quantitative analysis revealed that the complexes exhibited significant chiral selectivity, with Δ-1 demonstrating a stronger binding affinity for triplex RNA than Λ-1. Luminescence titration experiments further supported the binding of the complexes via intercalation. CD analysis demonstrated that both Λ-1 and Δ-1 could significantly induce conformational changes in the triplex RNA, and strong intermolecular interactions between the complexes and triplex RNA were observed, further suggesting a potential intercalative binding mode. The thermal denaturation results revealed that the third strand was selectively and markedly stabilized. The stabilization of the third strand in the triplex RNA was significantly enhanced by both enantiomers, while exerting negligible effects on the template duplex. The chiral ruthenium(II) complex developed in this study exhibits specific stabilization of triplex RNA, providing an effective strategy for stabilizing triplex RNA structures.

The classical diastereomeric salt resolution approach was employed to separate (±)-1,3-diphenyl-3-(phenylamino)propan-1-one using both enantiomers of 10-camphorsulfonic acid (CSA) as resolving agents. Gentle stirring at room temperature resulted in the stereoselective precipitation of a single diastereomeric salt, yielding a solid phase highly enriched in one enantiomer of the target compound. Control experiments confirmed the crucial role of the chiral counterion in directing the selectivity of the process. Molecular Dynamics simulations and subsequent Principal Component Analysis revealed slight but significant differences in the pre-nucleation size distribution of ionic clusters and in the dynamics of their mutual interconversion, hence suggesting that these differences could play a role in the racemic resolution.

Doenjang is the most used fermented soy product in Asian countries. At present, the simultaneous determination of DL-amino acids and histamine in doenjang has not been reported. Therefore, an UHPLC-MS/MS method was developed based on a novel chiral derivatization probe DBD-M-Pro, enabling for the first time the simultaneous quantification of 10 DL-amino acids and histamine in doenjang samples from different regions. Achieving resolution (Rs) values of 1.62-6.31 for the 10 DL-amino acids. The limits of detection (LODs) for DL-amino acids and histamine ranged from 0.54 to 15.62 pmol. The intraday and interday precision (RSD) were 0.21%-10.63%, and the average recoveries were 93.18%-109.07%. This method was applied to analyze 12 doenjang samples from Northeastern China, Korea, and Japan. The results showed that there was a significant geographical distribution of DL-amino acids and histamine. Yanbian Korean doenjang from China showed a unique advantage in that the total amount of DL-amino acids was significantly higher than that from other regions, with histamine concentration generally increasing with longer fermentation times. This study provides a stable and reliable method for the simultaneous determination of chiral amino acids and histamine in fermented foods such as doenjang.

Asymmetric homogeneous oxidation reactions catalyzed by first-row transition metal complexes have been summarized, focusing on the performance of the chiral catalyst and its relation with the key factors (structure of the chiral ligands, type of metal, solvent, temperature, and oxidant) in the catalytic systems. A variety of oxidants, including hydrogen peroxide (H2O2), molecular oxygen (O2), sodium hypochlorite (NaOCl), tert-butyl hydroperoxide (TBHP), and iodosylbenzene (PhIO), have been employed for the oxidation reactions using different chiral transition metal complexes. This review is mainly focused on the reports of various asymmetric metal complexes as homogeneous catalysts derived from first-row transition metals and chiral ligands for a range of oxidation reactions, such as epoxidation of olefins and α,β-unsaturated carbonyl compounds, sulfoxidation, hydroxylation, dihydroxylation, and oxidation of spirocyclic compounds. Several chiral ligands and their metal complexes (including metals titanium, chromium, manganese, iron, cobalt, and vanadium) are utilized in asymmetric oxidation reactions, whereas asymmetric manganese complexes have been extensively used for epoxidation, hydroxylation, and oxidative kinetic resolution. This review provides a clear and broad perception for better recognizing the homogeneous asymmetric catalysts used in oxidation reactions.

Chirality transfer from molecules to supramolecular architectures underpins diverse biological and material functions, yet constructing helical heterojunctions remains a formidable challenge. Here, we report the discovery of nanoscale helical junctions directed by a molecular chiral junction derived from a meso-form lipid emitter with two heterochiral centers. Unlike enantiopure molecules, which assemble into uniform homochiral fibers, the meso-form molecule self-assembles into planar belts in pure DMSO and striking helical heterojunctions with opposite-handed portions in DMSO/H2O 9:1 (v/v). Spectroscopic and structural analyses reveal that solvent polarity and stereochemical configuration govern distinct packing modes and hierarchical chirality amplification. This unprecedented molecular-to-supramolecular transformation provides a new paradigm for chirality engineering, offering mechanistic insights into chiral self-assembly and opening opportunities for advanced chiroptical materials.