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In this work, 5‐SIDipp [SIDipp=1,3‐bis(2,6‐diisopropylphenyl)‐imidazolin‐2‐ylidene] (1) derived Chichibabin's hydrocarbon with an octafluorobiphenylene spacer (3) has been reported. The addition of two equivalents of 5‐SIDipp with decafluorobiphenyl in presence of BF3 gives the double C−F bond activated imidazolium salt with two tetrafluoroborate anions, 2. Further reduction of 2 gives the fluorine substituted 5‐SIDipp based Chichibabin's hydrocarbon, 3. Quantum chemical calculations suggested a singlet state of 3 with a singlet–triplet energy gap (ΔES‐T) of 3.7 kcal mol−1, which is substantially lower with respect to the hydrogen substituted NHC‐based Chichibabin's hydrocarbons (10.7 kcal mol−1, B3LYP). As a result, the diradical character (y) of 3 (y=0.62) is also noticeably higher than the hydrogen substituted CHs (y=0.41–0.43). The ▵ES‐T was found to be higher in CASSCF (22.24 kcal mol−1) and CASPT2 (11.17 kcal mol−1) for 3 and the diradical character (d) is 44.6 %. [ABSTRACT FROM AUTHOR]

This paper describes the rare use of a 6‐membered saturated N‐heterocyclic carbene (NHC) known as 1,3‐di(2,6‐diisopropylphenyl) tetrahydropyrimidine‐2‐ylidene (abbreviated as 6‐SIDipp) as a ligand in zinc chemistry. We report on the investigation of the reactions between 6‐SIDipp and ZnX2, which resulted in a range of new monomeric 6‐SIDipp⋅ZnX2 complexes (X=Et (1), Cl (2), Br (3), and I (4)). We also prepared a new NHC zinc complex where the two substituents of the zinc atom are different, 6‐SIDipp⋅Zn(Et)Br (7) through the reaction of the proligand [6‐SIDippH]Br with ZnEt2. We have observed that the reactions of complex 1 with sulfur and HBpin led to the removal of the ZnEt2 moiety, resulting in the formation of a C=S double bond and a B−H activation product, respectively. Lastly, the reaction of 1 with five‐membered NHCs led to the exchange of carbene and the formation of either 5‐IDipp⋅ZnEt2 (8) or 5‐SIDipp⋅ZnEt2 (9). [ABSTRACT FROM AUTHOR]

Herein, we report two 2,2′-pyridylpyrrolide (PyPyrH) ligand supported magnesium complexes (1 and 2), which demonstrate bright luminescence with a quantum yield of 22% and 14% in the solid state, respectively. Theoretical calculations reveal that their emissive properties originate from the intra- and inter-ligand charge transfer. [ABSTRACT FROM AUTHOR]

P(NDI2OD-T2), also known as Polyera ActivInk N2200, was synthesized by the atom-economic direct hetero arylation polymerization (DHAP) route using a newly designed A–B–A monomer. The new monomer design involved flanking naphthalene diimide with bithiophene units in the bay position, which was further polymerized with bay substituted 1,4-dibromo naphthalene diimide, to afford the same polymer structure as P(NDI2OD-T2). The new monomer design resulted in a very high molecular weight (Mn: 99.5 kDa, ĐM: 2.8) defect-free polymer in a quantitative yield by the DHAP batch process using 1,2,4-trichlorobenzene (TCB) as the solvent. DFT studies revealed that the abstraction of the α-proton from the naphthalene diimide substituted 2,2′-bithiophene was favorable by 2.6 kcal mol−1 (ΔΔG) as compared to that from 2,2′-bithiophene. The reason for this improved C–H activation at the α position can be attributed to the presence of C–H⋯π stabilizing interactions in naphthalene diimide substituted 2,2′-bithiophene, which strengthens upon the extended charge delocalization throughout the ring, thus stabilizing the conjugate base generated after the proton abstraction. Continuous flow polymerization was carried out by pumping the DHAP reaction mixture including the monomers, catalyst, and additive (pivalic acid) solubilized in degassed TCB through a pre-heated glass condenser packed with K2CO3 and Celite under aerobic conditions. Reproducible molecular weights of Mn: 29.5 kDa, ĐM: 1.7 were obtained at much lower concentrations of reactant mixture compared to that for batch polymerization. This is the first report of the synthesis of P(NDI2OD-T2) by a Continuous Flow Process adopting the DHAP route to obtain a defect-free polymer with reasonable molecular weights. P(NDI2OD-T2) was also synthesized by Stille polymerization as a reference control sample to compare the thermal and charge carrier transport properties of the DHAP polymers. Organic field-effect (OFET) mobility measurements indicated mobility values in the order of 10−3 cm2 V−1 s−1 for the DHAP batch polymer (using the novel monomer design). The P(NDI2OD-T2) synthesized by DHAP batch using the commonly used starting materials – bisbromo naphthalene diimide and bithiophene, exhibited OFET mobilities which were one order less, ∼10−4 cm2 V−1 s−1. This observation highlights the importance of structural design in the monomer to enhance reactivity and thereby the bulk properties using the DHAP route. [ABSTRACT FROM AUTHOR]

A glycerol‐triazole tethered rhodamine based colorimetric and fluorimetric sensor 3′,6′‐bis(diethylamino)‐2‐(((1‐(1,3‐dihydroxypropan‐2‐yl)‐1H‐1,2,3‐triazol‐4‐yl)methylene)aminospiro [isoindoline‐1,9′‐xanthen]‐3‐one (L1) is designed and synthesized for the selective recognition of Cu2+ ion. The sensor L1 allows naked eye detection of Cu2+ ion with a fast response (<1 min). Among the various metal ions tested, the sensor L1 shows selective binding with Cu2+ through turn‐on fluorescence mechanism. The sensor shows 1 : 2 binding stoichiometry with binding constant, Ka=1.1×106 M−2 as revealed by job's plot & Benesi‐Hildebrand plot (B−H plot), respectively. The detection limit of L1 with Cu2+ ion is found to be 3.3 μM. Further, the experimental results are also validated using density functional theoretical (DFT) study. The optimized geometries indicates that the formation of the L1‐Cu2+ complex is thermodynamically favourable by ΔG=−11.7 kcal/mol. The HOMO‐LUMO gap of the ligand L1 is found to be 3.49 eV, which decreases to 1.76 eV upon complexation with copper. [ABSTRACT FROM AUTHOR]

Aluminum metal pollution is considered as a primary limiting factor that reduced crop yield in South Asian subtropical country like India. In national context, Odisha contributes around more than 40% of total ore availability. Moreover, industrial mining and smelting aid are major concern for aluminum metal toxicity in territorial vicinity affecting the soil fertility, ecosystem and human health through food chain. The aluminum metal accumulation limits the soil fertility by antagonistic regulation of photosynthetic and nitrogen fixing microbiota. The increasing concern regarding aluminum pollution enterprise critical investigations for their bioremediation in contamination sites. In this notion, the current study was hypothesized to decrypt the rate limiting factors, their explicit mode of action and intracellular detoxification in a cyanobacterium, i.e., Westiellopsis prolifica isolated from ash pond of NALCO (National Aluminum Company Limited), Angul, Odisha. In the experimental setup, treatment with different concentrations of AlCl3 (0–0.1 mM) was marked a decline in the growth of the strain due to the adverse regulation of photosynthetic pigments. However, the enforcement of catalase (CAT), ascorbate peroxidase (APX), superoxide dismutase (SOD), guaiacol peroxidase (GPX) and glutathione reductase (GR) was critical for sustaining strain viability under oxidative imbalance. The observation of an increase in the antioxidant enzyme and MDA content was evident to sustain strain viability under such oxidative imbalance. The outcome of the anticipated study was apparent to demonstrate a colossal interlink between Al mediated induction of oxidative stress and their cellular detoxification via intracellular antioxidant enzymes and removal of H2O2 accumulation in cyanobacterium, W. prolifica. Aluminum metal toxicity renders growth of Westiellopsis prolifica via affecting photosynthesis associated pigments. Westiellopsis prolifica deploys antioxidant defense enzymes to combat against aluminum mediated oxidative upset. Intracellular antioxidant enzymes provoke cellular survival of Westiellopsis prolifica under excessive uptake of aluminum in contaminated habitats. [ABSTRACT FROM AUTHOR]

The synthetically modified green fluorescent protein chromophore analogue 3,4,5‐trimethoxybenzylidene imidazolinone (1) yielded five polymorphs (I, II, III, IV, V) concomitantly irrespective of the solvent used for crystallization. The pentamorphic modification of 1 is solely due to the interplay of iso‐energetic weak intermolecular interactions in molecular associations as well as the conformational flexibility offered by a C—C single bond, which connects the electron‐deficient moiety imidazolinone with the electron‐rich trimethoxybenzylidene group. A common structural feature observed in all the polymorphs is the formation of a 'zero‐dimensional' centrosymmetric dimeric unit through a short and linear C—H...O hydrogen bond engaging phenyl C—H and imidazolinone carbonyl oxygen. However, the networking of these dimeric units showed a subtle difference in all the polymorphs. The 2D isostructurality was observed between polymorphs I, II and III, while the other two polymorphs IV and V revealed only 'zero‐dimensional' isostructurality. The different fluorescence emissions of Form I (blue) and Forms II to V (yellow) were attributed to the differences in π‐stacking interactions. It shows that one can modulate the photophysical properties of these smart materials by slightly altering their crystal structure. Such an approach will aid in developing new multi‐colour organic fluorescent materials of varying crystal structures for live‐cell imaging and fluorescent sensing applications. [ABSTRACT FROM AUTHOR]

The purpose of this study is to compare women with major depression against their matched healthy controls about their coping mechanisms and the severity of their symptom condition. Method: This cross-sectional hospital-based survey recruited 37 women with major depression and 40 non-depressed women as healthy controls. Simple random sampling was used to select the participants. Data was collected by using self-reported tools. Descriptive statistics and interpretative analysis of data was performed by using independent-samples t-test, ANOVA, and post hoc Tukey HSD multiple comparison tests to find out the accurate differences between levels of depression. The results show that women who used more self-blame, rumination bordering on to brooding, and less positive reframing had higher levels of depressive symptoms. Among the positive coping mechanisms, it was noted that in the clinical sample used instrumental and emotional supports. With regard to negative strategies for coping depression, self-blame, self-distraction, denial and venting were common. The use or non-use of a given coping mechanisms varied with the severity of depression. Conclusion: The study concludes that women with major depression use qualitatively different coping mechanisms for coping depression than healthy controls. This has implications for planning psychotherapeutic programs for the affected women. [ABSTRACT FROM AUTHOR]

In this paper, we have used two N,O‐ketiminato ligands (L1 and L2) with biphenyl and terphenyl substituent on the nitrogen atom. Deprotonation of L1 with KN(SiMe3)2 and subsequent reaction with MgI2 led to a homoleptic dinuclear magnesium complex (1) with a Mg2O2 four‐membered ring. Deprotonation with nBuLi and subsequent reaction with MgI2 afforded a unusual dinuclear magnesium complex (2) with a Mg2O2 ring. Extension of the ligand for calcium resulted in a trinuclear calcium complex (3) with six four‐membered Ca2O2 rings. We could not isolate any chelating complex when L2 was used as a ligand, and only oxygen bound magnesium (4) and calcium (5) adducts were isolated. DFT studies were performed to understand this dissimilar behavior. More diverse results were obtained when lithiated L1 and L2 were treated with germanium dichloride. We were able to stabilize a monomeric germylene monochloride (7) with L1. However, with L2, an unusual ligand scrambling, and a C−C coupling take place, leading to the formation of a secondary carbocation with GeCl3‐ as a counter‐anion (8). Besides, a germanium dichloride adduct (9) bound to the oxygen center of the ligand was obtained as the minor product. [ABSTRACT FROM AUTHOR]

Emotional dysregulation is a central topic of interest in many clinical studies. It plays a vital role in making or breaking interpersonal and interpersonal relationships in clinical populations as well as healthy controls. This study seeks to investigate the nature, intensity and extensity patterns of emotional regulation in patients diagnosed as major depression (N: 254) and borderline personality disorder (N: 69). By using a one-shot cross sectional purposive sample survey design, this hospital-based study targeted a random sample of subjects from both gender between 18-30 years. Following clinical interviews and diagnosis as per the chosen inclusion and exclusion criteria, participants were recruited based on ICD-10 criteria and after they secured a minimum cut-off score on McLean’s Screening Instrument for Borderline Personality Disorder and Hamilton Depression Rating Scale. The selected participants were administered Difficulties in Emotion Regulation Scale and Cognitive Emotion Regulation Questionnaire. Results show significantly high scores on emotion regulation in patients with borderline personality disorder than major depressive disorder (p:<0.05). These differences are maintained across all domains except for cognition mediated areas like ‘awareness’, ‘self-blame’, ‘acceptance’, ‘rumination’, and ‘positive refocusing’. Associated variables like genderand marital status appear to influence only some aspects of non-cognitive emotional dysregulation. The findings are discussed along with their implications for therapy in the context of cultural factors unique to Indian settings. [ABSTRACT FROM AUTHOR]

An oxidovanadium(V) complex [VO(SGly)(bpy)]ClO4 (H2SGly=N‐(2‐hydroxybenzyl)‐L‐glycine; bpy=2,2′‐bipyridine) was synthesized and characterized by spectroscopic studies (IR, UV‐vis, ESI‐MS). The theoretical structure of the complex was optimized by density functional theory (DFT) calculations. The multifunctionality of this oxidovanadium complex was demonstrated by the application of it as a catalyst in peroxidative bromination of single‐pot conversion of phenol red to bromophenol blue, whereas its nuclease activity was established by DNA cleavage. The interaction of this oxidovanadium complex with DNA was studied by various physicochemical tools like UV‐vis, fluorescence, and viscosity measurement studies. The intrinsic binding constant of the complex with DNA was determined spectrophotometrically and calculated to be (2.3 ± 0.02) x 104 M−1. The spectroscopic studies and the viscosity measurements indicate that the complex binds to the groove of CT‐DNA, but whether to the major or minor groove that was not established. The extent of vanadium complex induced DNA cleavage was studied by gel electrophoresis techniques. The complex was found to promote cleavage of pUC19 plasmid DNA from the super coiled (SC DNA) form I to nicked coiled (NC DNA) relaxed form II. [ABSTRACT FROM AUTHOR]

COVID-19—a severe acute respiratory syndrome disease caused by coronavirus 2 (SARS-CoV-2)—has recently attracted global attention, due to its devastating impact, to the point of being declared a pandemic. The search for new natural therapeutic drugs is mandatory, as the screening of already-known antiviral drugs so far has led to poor results. Several species of marine algae have been reported as sources of bioactive metabolites with potential antiviral and immunomodulatory activities, among others. Some of these bioactive metabolites might be able to act as antimicrobial drugs and also against viral infections by inhibiting their replication. Moreover, they could also trigger immunity against viral infection in humans and could be used as protective agents against COVID-In this context, this article reviews the main antiviral activities of bioactive metabolites from marine algae and their potential exploitation as anti-SARS-CoV-2 drugs. [ABSTRACT FROM AUTHOR]

A glycerol‐triazole tethered rhodamine based colorimetric and fluorimetric sensor 3′,6′‐bis(diethylamino)‐2‐(((1‐(1,3‐dihydroxypropan‐2‐yl)‐1H‐1,2,3‐triazol‐4‐yl)methylene)aminospiro [isoindoline‐1,9′‐xanthen]‐3‐one (L1) is designed and synthesized for the selective recognition of Cu2+ ion. The sensor L1 allows naked eye detection of Cu2+ ion with a fast response (<1 min). Among the various metal ions tested, the sensor L1 shows selective binding with Cu2+ through turn‐on fluorescence mechanism. The sensor shows 1 : 2 binding stoichiometry with binding constant, Ka=1.1×106 M−2 as revealed by job's plot & Benesi‐Hildebrand plot (B−H plot), respectively. The detection limit of L1 with Cu2+ ion is found to be 3.3 μM. Further, the experimental results are also validated using density functional theoretical (DFT) study. The optimized geometries indicates that the formation of the L1‐Cu2+ complex is thermodynamically favourable by ΔG=−11.7 kcal/mol. The HOMO‐LUMO gap of the ligand L1 is found to be 3.49 eV, which decreases to 1.76 eV upon complexation with copper. [ABSTRACT FROM AUTHOR]

Fucoidan is a complex polysaccharide (molecular weight 10,000–100,000 Da) derived from brown algae which comprises of L-fucose and sulfate groups have potential as therapeutic diligences against several human diseases. The fucoidan has expanded a widespread range of pharmacological properties as an anti-inflammatory, anticoagulant, antiangiogenic, immunomodulatory, anti-adhesive, anticancer, antidiabetic, antiviral and anti-neurodegenerative agents owing to their diverse chemical conformation and potent antioxidant activity. The antioxidant and immunomodulatory activities of the fucoidan contribute towards their disease preventive potency through dynamic modulation of key intracellular signalling pathways, regulation of ROS accumulation, and maintenance of principal cell survival and death pathways. Additionally, it also reduces cancer-associated cachexia. Despite the wide range of therapeutic potency, the fucoidan is heavily regarded as an unexplored plethora of druggable entities in the current situation. The isolation, screening, biological application, pre-clinical, and clinical assessment along with large scale cost-effective production remain a foremost task to be assessed. Moreover, the chemical synthesis of the present bioactive drug with confirmational rearrangement for enhanced availability and bioactivity also need tenacious investigation. Hence, in the present review, we give attention to the source of isolation of fucoidan, their principle strategic deployment in disease prevention, and the mechanistic investigation of how it works to combat different diseases that can be used for future therapeutic intervention. [ABSTRACT FROM AUTHOR]

Our study introduces the design of inverse sandwich (iSw) complexes incorporating a noble gas compound: xenon trioxide (XeO 3 ). Through comprehensive computational analyses, we have investigated the critical factors influencing their stability by employing a variety of state-of-the-art computational tools. We demonstrated that the coordination number of xenon in the iSw complex of XeO 3 with 18-crown-6 is influenced by the presence of a rare, weakly stabilizing Xe···Xe interaction between the XeO 3 molecules. Furthermore, we observed that the stability of iSw complexes of 1,3,5-triphenylbenzene (TPB) and its derivatives is not solely attributed to aerogen bonding, but also involves contributions from C-H···O interactions and back-donation from the lone pair of Xe to the antibonding C-C orbitals of TPB. Additionally, the significant contributions from orbital interactions and dispersion interactions in the TPB derivatives highlight the multifaceted amphoteric properties of XeO 3 and reveal that the iSw complexes of TPB and derivatives are not predominantly governed by electrostatic interactions, contrary to conventional belief.

Various aza-crowns with different sizes and substituents have been explored computationally as potential hosts for stabilizing the explosive guest xenon trioxide (XeO3) through σ-hole-mediated aerogen bonding interactions. Interestingly, aza-crowns demonstrate superior binding towards XeO3 compared to their oxygen and thio counterparts. However, unlike the latter cases, where the binding was found to be increasingly favorable with the increase in the size of the crowns, aza-crowns exhibit a variable size preference for XeO3, peaking with aza-15-crown-5, and reducing thereafter with increase in crown size., (© 2024 Wiley‐VCH GmbH.)

In order to control the explosiveness and shock sensitivity of XeO 3 , we have investigated its plausible interaction with various non-aromatic coordinating solvents, serving as potential Lewis base donors, through density functional theory (DFT) calculations. Out of twenty six such solvents, the top ten were thus identified and then thoroughly examined by employing various computational tools such as the mapping of the electrostatic potential surface (MESP), Wiberg bond indices (WBIs), non-covalent interaction (NCI) plots, Bader's theory of atoms-in-molecules (AIM), natural bond orbital (NBO) analysis, and the energy decomposition analysis (EDA). The amphoteric nature of XeO 3 was also explored by investigating the extent of back donation from the lone pair of Xe to the antibonding orbital of the donating atom/group of the solvent molecules. The C-H…O interactions were also found to be a contributing factor in the stabilization of these adducts. Although these aerogen-bonding interactions were found to be predominantly electrostatic, significant contributions from the orbital contributions, as well as dispersion interactions, were observed. The top three non-aromatic solvents (among the twenty six studied) which form the strongest adducts with XeO 3 are proposed to be hexamethylphosphoramide (HMPA), N,N'-dimethylpropyleneurea (DMPU) and tetramethylethylenediamine (TMEDA)., (© 2024 Wiley-VCH GmbH.)

A series of Cu-Ag bimetal alloys decorated on SiO 2 and the fabrication of few-layer S-doped graphitic carbon nitride (SC) warped over it to form a core-shell nanostructured morphology have been demonstrated and well characterized through various physiochemical techniques. HRTEM data confirmed the formation of a compact nanojunction between the SiO 2 and SC, where Cu-Ag is embedded uniformly with an average particle size of 1.3 nm. The Ag : Cu (1 : 3) between SiO 2 and SC produces 1730 μmol h -1 g -1 of H 2 under visible light illumination. Moreover, 6.2-fold current enhancement in the case of Ag : Cu (1 : 3) as compared to the Ag-loaded core-shell nanostructured photocatalyst indicates higher electron-hole-pair separation. The excellent activity was due to the synergistic alloying and plasmonic effect of Ag and Cu. DFT studies reveal that the Cu atom in the Cu-Ag bimetal alloy plays a pivotal role in the generation of H 2 , and the reaction proceeds via a 4-membered transition state. The mechanistic insight proceeds from the generation of hot electrons due to the LSPR effect and their transfer to the SC layer via a compact nanojunction., Competing Interests: The authors declare no competing financial interest., (This journal is © The Royal Society of Chemistry.)

At the dawn of the Universe, the ions of the light elements produced in the Big Bang nucleosynthesis recombined with each other. In our present study, we have tried to mimic the conditions in the early Universe to show how the recombination process would have led to the formation of the first ever formed diatomic species of the Universe: HeH + , as well as the subsequent processes that would have led to the formation of the simplest triatomic species: H 3 + . We have also studied some special cases: higher positive charge with fewer number of hydrogen atoms in a dense atmosphere, and the formation of unusual and interesting linear, dicationic He chains beginning from light elements He and H in a positively charged atmosphere. For all the simulations, the ab initio nanoreactor ( AINR ) dynamics method has been employed., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Dash, Das and Vanka.)

Metal-organic frameworks (MOFs) show distinctive superiority for carbon dioxide (CO 2 ) capture and luminescent sensing of toxic pollutants over other materials, where combination of both of these properties together with improvement of hydrolytic stability and pore functionality is critical to environmental remediation applications. The Ni(II) framework [Ni 2 (μ 2 -OH)( azdc )( tpim )](NO 3 )·6DMA·6MeOH ( CSMCRI-3 ) ( tpim = 4,4',4″-(1 H -imidazole-2,4,5-triyl)tripyridine, H 2 azdc = azobenzene-4,4'-dicarboxylic acid, DMA = dimethylacetamide, CSMCRI = Central Salt & Marine Chemicals Research Institute), encompassing cationic [Ni 2 (μ 2 -OH)(CO 2 ) 2 ] SBUs, is solvothermally synthesized from nitrogen-rich and highly fluorescent organic struts. The noninterpenetrated structure, containing free nitrogen atom affixed microporous channels, is stable in diverse organic solvents and weakly basic and acidic aqueous solutions. The activated MOF ( 3a ) exhibits strong CO 2 -framework interaction and extremely selective CO 2 adsorption over N 2 (292.5) and CH 4 (11.7). Importantly, water vapor exposure does not affect the surface area and/or multiple CO 2 uptake-release cycles, signifying potential of the porous structure for long-term use under humid conditions. Aqueous-phase sensing studies illustrate extremely specific and ultrafast detection of explosive 2,4,6-trinitrophenol (TNP) via remarkable fluorescence quenching ( K SV = 1.3 × 10 5 M -1 ), with a 0.25 ppm limit of detection (LOD). Furthermore, 3a serves as unique luminescent probe for highly discriminative and quick responsive detection of three noxious oxo-anions (Cr 2 O 7 2- , CrO 4 2- , MnO 4 - ) in water via noteworthy turn-off responses and extreme low LODs (Cr 2 O 7 2- 0.9; CrO 4 2- 0.29; MnO 4 - 0.25 ppm). It is imperative to stress the outstanding reusability of the MOF toward multicyclic sensing of all four major water contaminants, alongside visible colorimetric changes upon individual analyte detection. Mechanistic insights in light of the electron transfer route together with density functional theory calculations portray the influence of pore functionalization in framework-analyte interactions, including alternation in energy levels, where varying degrees of contribution of energy transfer explicitly authenticates high quenching of the material.