The title compound, C26H22N6 [2+]·2Cl[-]·6H2O, crystallizes in the monoclinic space group P21/n with one mol-ecule in the asymmetric unit. Structure determination at 150 K from a two-component twin crystal reveals the non-symmetrical n-shaped dication, where two pyridine-imidazole fused cores bearing pendant pyridyl rings are linked by an ethyl-ene bridge. The fused five- and six-membered rings are almost coplanar with the largest deviation from the mean plane being 0.019 Å for a nitro-gen atom of one of the rings. The pendant pyridyl groups are twisted by 42.14 (11) and 46.47 (11)° with respect to the planes of the adjacent imidazo[1,5-a]pyridinium cores. In the crystal, the dications stacked along the b-axis direction are linked by π-π inter-actions that possibly stabilize the n-type structure in the solid state. The chloride anions and water mol-ecules form R [2] 4(8), R [5] 5(12), R [6] 6(12) and R [8] 11(22) ring motifs through O-H⋯O/Cl hydrogen bonds, building corrugated layers that run between columns of the stacked organic dications.

Hypochlorous acid (HClO) exerts diverse biological functions and has broad applications in daily life. Herein, a novel turn-on fluorescent probe, DCOH-OCl, was developed for HClO with rhodamine derivatives as the fluorescent group and N,N-dimethylthiocarbamate as the reactive group. The probe exhibited excellent performance, including fast response (30 s), wide pH range (3-10), high selectivity, and strong anti-interference capability. DCOH-OCl allowed quantitative determination of HClO in environmental and food samples and fluorescence imaging of HClO in living cells, zebrafish, and various plants. Especially, DCOH-OCl is the first fluorescent probe capable of visualizing HClO in medicinal plants. Furthermore, this probe enabled real-time and non-destructive monitoring of HClO fluctuations in wheat roots subjected to heavy metal stress. This study provides direct visual evidence of plant responses to heavy metal stress and offers a practical tool for agricultural research and crop safety assessment.

Hypochlorous acid (HOCl) is endogenously produced by neutrophils, macrophages, and other cells of the innate immune system and acts as a natural antiseptic. The active components are chlorine and reactive oxygen species in the form of a weak acid. It can be manufactured by electrolysis or chemical acidification of sodium or calcium hypochlorite, producing a mixed solution of HOCl and hypochlorite ions (OCl-) in equilibrium. The ratios of HOCl to OCl- within the solutions vary depending upon the manufacturing process and method used for stabilization. These ratios can change over time, and maintaining pH and storage conditions is essential to ensure a long shelf life. Hypochlorous acid solution has become favorable as an alternative skin preparation and skin care in aesthetics and dermatology. This review will examine the manufacture, toxicity, and efficacy of HOCl used in skin preparation and other areas of use in health care.

Hypochlorous acid (HOCl) serves as a vital molecule in innate immune defense, and fluctuations of lysosomal HOCl levels may be linked to a range of physiological and pathological processes, which make the quantitative detection of lysosomal HOCl a necessity. Herein, we report the design and synthesis of a novel fluorescent probe, PD-OCl, which is constructed by conjugating phenothiazine and dicyanoisophorone moieties and exhibits near-infrared (NIR) emission and large Stokes shifts. Notably, PD-OCl can function as a robust ratiometric fluorescent probe for HOCl detection, exhibiting exceptional selectivity, high sensitivity, and rapid response kinetics. Additionally, the PD-OCl has been successfully applied for monitoring both exogenous and endogenous HOCl in living cells, where it displays excellent lysosomal targeting capability, providing a visualized and ratiometric approach for tracing the variations of subcellular HOCl levels. This work establishes PD-OCl as a promising candidate for investigating lysosomal HOCl levels in LPS-induced oxidative stress state cells.

Tryptophan, one of the most oxidation-prone amino acids, forms distinct products with different reactive oxygen and nitrogen species, yet oxidant-specific fingerprints have not been compared. Untargeted LC-QTOF-MS profiled tryptophan oxidation in ammonium acetate buffer (pH 4.75) by 1O2, O3,•OH, O2NOOH, ONOOH, and OCl-. Feature intensities were hierarchically clustered and structurally assigned. Established markers (N'-formylkynurenine, oxindolylalanine, kynurenine, hydroxypyrroloindole carboxylic acid, and dioxindolylalanine) and a tryptophan dimer occurred across most conditions, while many oxidants also produced specific oxidized dimers. ONOOH and O2NOOH showed strongly overlapping nitration/nitrosation-dominated fingerprints, while ONOOH also prominently yielded pyridazinoindole, a previously unreported feature. O3 oxidation was characterized by quinoline-4-ol, kynurenine-related products, and multiple Trp+3O signals, whereas 1O2 favored hydroperoxypyrroloindole carboxylic acid, quinoline derivatives, and dimers involving fragmented tryptophan. •OH and OCl- yielded fewer unique features. Comparison with nonthermal plasma-treated tryptophan indicated ozone-dominated chemistry, with additional reactive nitrogen species contributions under humid multihollow surface dielectric barrier discharge conditions.

Long head of the biceps tendon pathology is a frequent cause of anterior shoulder pain. Tenotomy is technically simple but may lead to cosmetic deformity and muscle cramping, whereas tenodesis better preserves the biceps contour but involves a more complex procedure. Multiple surgical techniques and fixation methods are available. No single technique has emerged as clinically superior, and no gold standard has been established. Among the various techniques and fixation sites, subpectoral placement within cancellous bone has been proposed as a favorable option for long head of the biceps tendon tenodesis. This technical note describes a surgical approach-arthroscopic bicortical biceps anchorage-which combines subpectoral positioning, arthroscopic execution, and inlay fixation using a bicortical button. Nevertheless, the surgical technique is associated with a substantial learning curve and may involve a theoretical risk of neurovascular injury related to bicortical drilling. These considerations underscore the need for further biomechanical and clinical evaluation.