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In this report, we successfully engineered a novel probe based on an acceptor–donor–acceptor (A–D–A) architecture featuring dicyanovinyl-substituted thieno[3,2-b]thiophene, termed DCVTT. The designed probe self-assembles into luminous nanoparticles (DCVTT NPs) upon introducing mixed aqueous solutions. These fluorescent nanostructures served as a ratiometric probe for detecting cyanide (CN−) ions in aqueous-based environments, owing to the robust Intramolecular Charge Transfer (ICT) characteristics of DCVTT. The A–D–A substituents in DCVTT significantly enhanced ICT behavior by promoting more efficient electron transfer between the donor and acceptor groups. This improved electron transfer process leads to heightened sensitivity in detection applications. In the case of cyanide (CN) sensing, this enhanced ICT behavior manifests as a strong colorimetric response, allowing for a visible color change before and after interaction with cyanide. Speculation regarding the interaction mechanism between DCVTT and CN− is proposed based on the findings of various experimental analyses. The detection limit (LOD) for DCVTT in identifying CN− is 0.83 nM, significantly lower than the CN− concentration thresholds deemed safe by the World Health Organization (WHO) and the United States Environmental Protection Agency (EPA). Time-Dependent Density Functional Theory (TD-DFT) has been utilized to theoretically analyze the optical properties of DCVTT both before and after the introduction of the CN− ions. A paper-based test strip was developed to demonstrate its practical application to enable efficient qualitative CN− detection by visual inspection. Furthermore, this sensing platform demonstrates highly accurate quantitative detection of CN− in apple seeds. No prior reports have utilized fluorescence techniques to estimate apple seeds' CN levels. [ABSTRACT FROM AUTHOR]

Two new phenylsulfonylindole derivatives, namely, N-[[3-bromo-1-(phenyl- sulfonyl)-1H-indol-2-yl]methyl]-N-(4-bromo-3-methoxyphenyl)benzenesulfon- amide, C28H22Br2N2O5S2, (I), and N,N-bis[[3-bromo-1-(phenylsulfonyl)-1H- indol-2-yl]methyl]benzenesulfonamide, C36H27Br2N3OS3, (II), reveal the impact of intramolecular π-π interactions of the indole moieties as a factor not only governing the conformation of N,N-bis(1H-indol-2-yl)methyl)amines, but also significantly influencing the crystal patterns. For 1, the crystal packing is dominated by С-Н...π and π - π bonding, with a particular significance of mutual indole-indole interactions. In the case of II, the molecules adopt short intramolecular π-π interactions between two nearly parallel indole ring systems [with the centroids of their pyrrole rings separated by 3.267 (2) A] accompanied by a set of forced Br...O contacts. This provides suppression of similar inter- actions between the molecules, while the importance of weak C-H...O hydrogen bonding to the packing naturally increases. Short contacts of the latter type [C...O=3.389 (6) Å] assemble pairs of molecules into centrosymmetric dimers with a cyclic R²2(13) ring motif. These findings are consistent with the results of a Hirshfeld surface analysis and together they suggest a tool for modulating the supramolecular behavior of phenylsulfonylated indoles. [ABSTRACT FROM AUTHOR]

Two new [1-(phenyl­sulfon­yl)-1H-indol-2-yl]methanamine derivatives, namely, N-(3-methoxyphenyl)-N-{[1-(phenyl­sulfon­yl)-1H-indol-2-yl]methyl}acetamide, C24H22N2O4S, (I), and N-(2,5-di­meth­oxy­phen­yl)-N-{[1-(phenyl­sulfon­yl)-1H-indol-2-yl]meth­yl}benzene­sulfonamide, C29H26N2O6S2, (II), reveal a nearly orthogonal orientation of their indole ring systems and sulfonyl-bound phenyl rings. The sulfonyl moieties adopt the anti-periplanar conformation. For both compounds, the crystal packing is dominated by C—H⋯O bonding [C⋯O = 3.312 (4)–3.788 (8) Å], with the structure of II exhibiting a larger number, but weaker bonds of this type. Slipped π–π interactions of antiparallel indole systems are specific for I, whereas the structure of II delivers two kinds of C—H⋯π interactions at both axial sides of the indole moiety. These findings agree with the results of Hirshfeld surface analysis. The primary contributions to the surface areas are associated with the contacts involving H atoms. Although II manifests a larger fraction of the O⋯H/H⋯O contacts (25.8 versus 22.4%), most of them are relatively distal and agree with the corresponding van der Waals separations. [ABSTRACT FROM AUTHOR]

Three new 1H-indole derivatives, namely, 2-(bromo­meth­yl)-3-methyl-1-(phenyl­sulfon­yl)-1H-indole, C16H14BrNO2S, (I), 2-[(E)-2-(2-bromo-5-meth­oxy­phen­yl)ethen­yl]-3-methyl-1-(phenyl­sulfon­yl)-1H-indole, C24H20BrNO3S, (II), and 2-[(E)-2-(2-bromo­phen­yl)ethen­yl]-3-methyl-1-(phenyl­sulfon­yl)-1H-indole, C23H18BrNO2S, (III), exhibit nearly orthogonal orientations of their indole ring systems and sulfonyl-bound phenyl rings. Such conformations are favourable for inter­molecular bonding involving sets of slipped π–π inter­actions between the indole systems and mutual C—H⋯π hydrogen bonds, with the generation of two-dimensional monoperiodic patterns. The latter are found in all three structures, in the form of supra­molecular columns with every pair of successive mol­ecules related by inversion. The crystal packing of the compounds is additionally stabilized by weaker slipped π–π inter­actions between the outer phenyl rings (in II and III) and by weak C—H⋯O, C—H⋯Br and C—H⋯π hydrogen bonds. The structural significance of the different kinds of inter­actions agree with the results of a Hirshfeld surface analysis and the calculated inter­action energies. In particular, the largest inter­action energies (up to −60.8 kJ mol−1) are associated with pairing of anti­parallel indole systems, while the energetics of weak hydrogen bonds and phenyl π–π inter­actions are comparable and account for 13–34 kJ mol−1. [ABSTRACT FROM AUTHOR]

Byline: P. Gamage, M. Mohideen, Prasanna. Galhena, N. Weerasinghe, M. Kumbukage, Tharuka. Herath, Sunethra. Senanayake, D. Sirisena, S. Senanayake, Inuka. Gooneratne Background: The Radboud Oral Motor Inventory for Parkinson's disease [...]

Transition metal carbides and nitrides (MXenes) show a high potential for electrochemical energy storage in batteries and supercapacitors and for electrocatalysis. Their excellent electronic and magnetic characteristics have been highlighted in several theoretical studies. However, experimental research on MXenes is yet to confirm their predicted properties as candidates for controllable magnetic 2D materials. Here, we report our theoretical and experimental study of V2CTx MXenes (T = O, OH, F), providing key insights into their magnetism. Based on our density functional theory (DFT) analysis, we predicted ferromagnetic (FM) and antiferromagnetic (AFM) states of V2CTx, which are determined by the O/F ratio of surface functional groups. Accordingly, we prepared V2CTx MXenes in the form of multilayered powders and thin films with different O/F ratios. No experimental evidence of FM or AFM properties was found in any material. Nevertheless, powders and films with almost identical chemical compositions (in terms of O/F ratio) displayed different magnetic properties, whereas films with disparate chemical compositions revealed a similar magnetic character. Therefore, the preparation route and form of the final V2CTx material override the effect of the O/F ratio, which is often overestimated in theoretical studies. Moreover, these findings underscore the importance of preparing MXene materials to experimentally confirm their theoretically predicted properties. [ABSTRACT FROM AUTHOR]

Owing to their improved catalytic stability and ability to undergo repeated cycles, solid-supported catalysts show great potential for various catalytic reactions. In this study, we synthesized a catalyst comprising a palladium-2,2-bipyridine complex supported on TiO2 nanoparticles (TiO2@BDP-PdCl2) fully characterised and investigated its efficacy in Suzuki–Miyaura cross coupling reactions involving phenyl boronic acid with various aryl halides under mild reaction conditions. The 2,2′- bipyridine (bp) has shown excellent complexation properties for Pd (II) and it could be easily anchored onto functionalized TiO2 support by the bridging carboxylate ions. The composition and structure of the as-prepared catalyst was characterized by powder X-ray diffraction (PXRD), scanning electron microscopy (SEM), Transmission Electron Microscope (TEM), X-ray photoelectron spectroscopy (XPS), and UV–Vis spectroscopy. The catalyst easily demonstrated separability, enhancing its practicality in catalytic processes. Subsequent utilization showed a consistent activity level, suggesting the stabilization of the aggregated catalyst species. This research sheds light on the importance of catalyst stability and maintenance during consecutive reaction cycles. [ABSTRACT FROM AUTHOR]

We report a specific lysosome targeted light-responsive CO-releasing molecule (Lyso-CORM). Lyso-CORM is very stable under dark conditions. CO and singlet oxygen (1O2) generation was effectively triggered under one photon and two photon excitation (800 nm) conditions. The cytotoxicity results demonstrated that Lyso-CORM showed good phototoxicity due to the synergistic effect of CO and 1O2 release, and its good biocompatibility, negligible dark toxicity and specific lysosome targeting make Lyso-CORM a potent candidate for phototherapeutic applications. [ABSTRACT FROM AUTHOR]

Glory lily (Gloriosa superba L.) is one of the important medicinal plants which has attained commercial importance in Tamil Nadu in recent times. The medicinal value of glory lily is commendable which is attributed to the presence of alkaloids, chiefly „Colchicine and „Gloriosine. The drug has so far been obtained from collection from wild sources but of late, the indiscriminate exploitation of tubers has affected its supply badly. This has necessiated establishment of commercial plantations to meet the demand of pharmaceutical industries. Being a newly domesticated crop, the appropriate production technologies for this medicinal plant have not yet been standardized on a scientific footing. Among the technologies of crop production, the method of propagation assumes greater importance due to its marked effect on growth and yield. With this background, studies were undertaken to standardize the propagation methods in glory lily to find out the suitable growth regulators/chemicals to improve seed germination and seedling growth. The study was conducted at the Department of Horticulture, Faculty of Agriculture, Annamalai University. The results revealed that Gibberellic acid and ethrel treatments were found to accelerate the seed germination. GA3 @ 200 ppm resulted in early germination (23.35 days) as compared to dry seeds (Control) which took 57.76 days. The percentage of germination was the highest with 56.55% in GA3 @ 200 ppm as against the least in the control. Gibberellic acid @ 200 ppm followed by ethrel @ 200 ppm produced maximum number of roots. Thiourea @ 1000 ppm followed by GA3 @ 100 ppm were promising in improving the seedling height. Thiourea @ 1000 ppm followed by GA3 @ 100-200 ppm were promising in increasing the leaf number. The fresh and dry weight of shoot were maximum at GA3 @ 200 ppm, whereas the fresh and dry weight of roots were higher in cytokinin treatment (BA @ 50 ppm) followed by ethrel @ 200 ppm. [ABSTRACT FROM AUTHOR]