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In this study, we developed a nitrate-coordinated iron–nickel hydroxide [NC–FeNi(OH)2] catalyst for hydrazine oxidation-assisted seawater splitting. Replacement of O2 evolution by hydrazine oxidation in a two-electrode setup resulted in a cell voltage of 1.20 V at 100 mA cm−2. This represents a voltage reduction of 470 mV compared to conventional seawater splitting. Additionally, NC–FeNi(OH)2 demonstrated remarkable stability over a period of 60 hours. [ABSTRACT FROM AUTHOR]

Hydrazine, a compound known for its toxicity to human health and the environment, finds extensive use across various industries and potentially contributes to several diseases. Hence, the accurate measurement of hydrazine levels is paramount. This study introduces three new aggregation induced emissive luminogens (AIEgens) GBY-7, GBY-8, and GBY-9 crafted from benzofuran infused with a dicyanovinylidene group, tailored specifically for hydrazine monitoring. These probes feature a D–π–A core with a rotor, providing an optimal fluorescent base. Additionally, a potent electron-attracting nitrile group aids in the nucleophilic addition of N2H4 to form hydrazone, thereby blocking the intramolecular charge transfer (ICT) process and inducing optical signal modulation. Notably, luminogens GBY-8 and GBY-9 exhibit high selectivity in detecting hydrazine amidst competing amine-based compounds, showing detection limits of 0.00020 mM and 0.0043 mM, respectively. [ABSTRACT FROM AUTHOR]

Direct hydrazine fuel cells (DHFC) insist on the evolved and persistent electrocatalysts for anodic hydrazine oxidation reaction (HzOR). Herein, PdO promoted CuO heterostructures supported on γ‐Al2O3 are depicted as efficient electrocatalysts for HzOR. γ‐Al2O3 is prepared by precipitation method while metal precursors are incorporated by co‐impregnation technique. Physiochemically characterized PdO‐CuO/Al2O3 mesoporous composites displayed large electrochemical active surface area (ECSA) i. e., 0.18 cm2, high current density (j) i. e., 35.7 mA cm−2, larger diffusion coefficient (D°) i. e., 29.3×10−4 (cm2s−1), large apparent rate constant (kapp) i. e., 13.2 cm−1 with low charge transfer resistance (Rct) i. e., 3.6 kΩ shown by the best catalyst i. e., 1 % PdO‐CuO/Al2O3. Cyclic voltammetry indicated that the fabricated working electrodes offer high efficiency towards HzOR in alkaline medium in such a way that 1 % PdO‐CuO/Al2O3 produced 600 times higher oxidation current than CuO/Al2O3 composite. Owing to stability and reproducibility, PdO modified CuO/Al2O3 would achieve a huge catalytic significance in multiple electrochemical oxidation reactions with economic and ecological benefits. [ABSTRACT FROM AUTHOR]

A novel Rh‐catalyzed three‐component synthesis of N‐(o‐alkylaryl) pyrazoles via cascade pyrazole annulation and aryl C‐H conjugate addition to alkenes has been developed with enaminones, hydrazines, and functionalized alkenes as starting materials. The raw materials used in this reaction are simple, cheap, and readily available, and the reactions feature excellent step economy by furnishing products via the formation of a pyrazole ring and a key C‐H activation in one‐step operation. Moreover, the reaction proceeds smoothly under air atmosphere, making it easy to operate. [ABSTRACT FROM AUTHOR]

[Display omitted] The development of heterogeneous supported nanocatalysts with a high kinetics combined with low cost is off importance but remains still challenged for hydrazine hydrate served as a promising hydrogen storage material. Herein, by virtue of surficial functional groups, ultrafine NiRh NPs were monodispersed on the two-dimensional V 2 C surface via a conventional wet chemical co-reduction. The optimized NiRh/V 2 C system demonstrates an excellent catalytic performance toward selectively catalyzing dehydrogenation of hydrazine hydrate, affording 100% H 2 selectivity with the turnover frequency (TOF) value of 987.5 h−1 at 323 K. Such an enhancement is mainly attributed to synergistic effect of nanosystem, which will optimize local surface energy and promote electron transfer in NiRh/V 2 C system, thereby improving the kinetic selectivity of catalytic hydrazine hydrate decomposition. This work has provided a facile strategy for developing nanocatalysts with high kinetics that could enable huge industrial applications in the future. [ABSTRACT FROM AUTHOR]

Based on the theory of nonisothermal chain reactions developed in the studies presented in the previous chapters, an experimentally verified explanation is given for the anomalous behavior of pyrolysis and combustion of a technically important product—hydrazine. The revealed kinetic features of N2H3 radicals, which led to the unusual properties of the hydrazine-oxygen ignition peninsula, are also explained. The mechanism of easy ignition and explosion has been clarified. [ABSTRACT FROM AUTHOR]

The synthesized Ru-MoNi/MoO 2 possesses superior bifunctional activities for HER and HzOR, requiring only −13 mV and −34.5 mV in 1 M KOH and 1 M KOH + 0.5 M N 2 H 4 , respectively, for achieving 10 mA cm−2. With Ru-MoNi/MoO 2 in a dual-electrode cell, only 0.57 V is needed to achieve 50 mA cm−2 with good stability, facilitating hydrazine-assisted OWS. [Display omitted] Improving the efficiency of overall water splitting (OWS) is crucial due to the slow four-electron transfer process in the oxygen evolution reaction (OER). The coupling of the thermodynamically favorable hydrazine oxidation reaction (HzOR) with the hydrogen evolution reaction (HER) significantly boosts hydrogen production. A Ru-decorated MoNi/MoO 2 micropillar (Ru-MoNi/MoO 2) has been synthesized using a hydrothermal followed by reduction annealing. Benefiting from Ru moderating the active interface of Mo-based alloys/oxides and the unique one-dimensional micropillar morphology. The synthesized Ru-MoNi/MoO 2 exhibits outstanding bifunctional activity for HER and HzOR, achieving 10 mA cm−2 at merely −13 mV and −34 mV in 1 M KOH and 1 M KOH + 0.5 M N 2 H 4 , respectively. Notably, with Ru-MoNi/MoO 2 in a dual-electrode setup, only 0.57 V is needed to achieve 50 mA cm−2, demonstrating good stability and facilitating hydrazine-assisted water splitting (OHzS). This work offers insights into the modulation of alloy/metal oxide active interfaces, contributing to the development of efficient bifunctional catalysts for HER and HzOR. [ABSTRACT FROM AUTHOR]

The determination of formaldehyde (HCHO) concentration in human exhaled breath can be used as an effective means for the early diagnosis of lung cancer. Lanthanide metal–organic frameworks (LnMOFs) have shown great potential in formaldehyde fluorescence sensing, yet challenges persist in achieving high sensitivity and selectivity. In this work, we report new hydrazine-functionalized LnMOFs (Ln = Eu3+, Gd3+, Tb3+, H2BDC–NH–NH2 = 2-hydrazine-terephthalic acid), having an fcu topology for the sensitive and selective detection of formaldehyde gas. The ligands with hydrazine groups not only act as an "antenna effect" between the ligands and Eu3+ ions, but also act as formaldehyde recognition sites, enabling Eu-BDC–NH–NH2 to be used for fluorescence enhanced sensing of formaldehyde gas in gaseous environments. Eu-BDC–NH–NH2 thus exhibits low detection limit (41.7 ppb), high selectivity, and fast (3 minutes) formaldehyde gas response, showing great potential to be practically applied in the field of early diagnosis of lung cancer. [ABSTRACT FROM AUTHOR]

The hydrazine oxidation‐assisted H2 evolution method promises low‐input and input‐free hydrogen production. However, developing high‐performance catalysts for hydrazine oxidation (HzOR) and hydrogen evolution (HER) is challenging. Here, we introduce a bifunctional electrocatalyst α‐MoC/N−C/RuNSA, merging ruthenium (Ru) nanoclusters (NCs) and single atoms (SA) into cubic α‐MoC nanoparticles‐decorated N‐doped carbon (α‐MoC/N−C) nanowires, through electrodeposition. The composite showcases exceptional activity for both HzOR and HER, requiring −80 mV and −9 mV respectively to reach 10 mA cm−2. Theoretical and experimental insights confirm the importance of two Ru species for bifunctionality: NCs enhance the conductivity, and its coexistence with SA balances the H ad/desorption for HER and facilitates the initial dehydrogenation during the HzOR. In the overall hydrazine splitting (OHzS) system, α‐MoC/N−C/RuNSA excels as both anode and cathode materials, achieving 10 mA cm−2 at just 64 mV. The zinc hydrazine (Zn−Hz) battery assembled with α‐MoC/N−C/RuNSA cathode and Zn foil anode can exhibit 97.3 % energy efficiency, as well as temporary separation of hydrogen gas during the discharge process. Therefore, integrating Zn−Hz with OHzS system enables self‐powered H2 evolution, even in hydrazine sewage. Overall, the amalgamation of NCs with SA achieves diverse catalytic activities for yielding multifold hydrogen gas through advanced cell‐integrated‐electrolyzer system. [ABSTRACT FROM AUTHOR]

AbstractIsosorbide dinitrate and hydralazine hydrochloride tablets treat heart failure in addition to conventional therapy, prolong hospitalization for heart failure, and enhance patient-reported functional status. LC-MS/MS methods developed and validated separately for the quantification of hydrazine mono-lactose adduct and hydrazine di-lactose adduct impurities in the isosorbide and hydralazine hydrochloride tablets. Separation of hydrazine mono-lactose adduct impurity achieved on ZIC-HILIC (100 × 4.6 mm, 5 µm) column with 0.1% formic acid in water as mobile phase A and acetonitrile as mobile phase B. The HPLC method gradient elution is; Tmin/% of B: 0/90, 15/40, 15.1/90, and 20/90. The flow rate is 1.0 mL per minute, and the injection volume is 20 µL. Separation of hydrazine di-lactose adduct impurity achieved on Inertsil HILIC (150 × 4.6 mm, 5 µm) column with 10 Mm ammonium acetate in water as mobile phase A and acetonitrile as mobile phase B. The HPLC method gradient elution is; Tmin/% of B: 0/90, 15/40, 15.1/90, and 18/90. The flow rate is 1.0 mL per minute, and the injection volume is 40 µL. Method validation has demonstrated both methods are specific, sensitive, linear, precise, accurate, stable and robust. [ABSTRACT FROM AUTHOR]

This work includes the synthesis of new pyrazoline derivatives 6-20 over two steps. The first step included a condensation between vanillin and various aromatic ketones (acetophenone, p-nitroacetophenone, p-chloroacetophenone, pbromoacetophenone, and 2-acetylnaphthalene) to provide the corresponding chalcone derivatives 1-5 in high yields (up to 93%). The second step involved a reaction of 1- 5 with hydrazine hydrate, phenyl hydrazine, and p-nitrophenyl hydrazine, which gave the desired products 6-20 in yields ranging from 60 to 85%. The structures of the prepared compounds were confirmed by FT-IR and 1H NMR spectroscopy. A few of the produced compounds were tested for antibacterial and antioxidant properties. [ABSTRACT FROM AUTHOR]

Widely utilized in the chemical industry and agriculture, hydrazine is easily absorbed by living things and can cause physical harm when in touch for an extended period of time. As a result, a novel cinnamaldehyde chalcone C5 was produced by Friedel Crafts process and aldol condensation reaction. Triphenylamine was used as the raw material for hydrazine determination in both reactions. Chalcone C5 exhibits significant AIE behavior in a mixed mixture of ethanol and water in addition to having great selectivity and a low detection limit (0.119 nm) for hydrazine. The solvent effect test revealed a linear relationship between the Stokes shift of C5 in the solvent and the rise in solvent orientation polarization. It is important to note that C5 is not harmful to MCF-7 cells, mouse kidney cells, or pig kidney cells. Furthermore, research on cell imaging has demonstrated that probe C5 may be utilized to image the fluorescence of hydrazine in active MCF-7 cells. [ABSTRACT FROM AUTHOR]

A highly efficient and chemoselective approach for the divergent assembling of unsymmetrical hydrazines through an unprecedented intermolecular desulfurdioxidative N−N coupling is developed. This metal free protocol employs readily accessible N‐arylhydroxylamines and N‐sulfinylanilines to provide highly valuable hydrazine products with good reaction yields and excellent functional group tolerance under simple conditions. Computational studies suggest that the in situ generated O‐sulfenylated arylhydroxylamine intermediate undergoes a retro‐[2π+2σ] cycloaddition via a stepwise diradical mechanism to form the N−N bond and release SO2. [ABSTRACT FROM AUTHOR]

A strategy for the synthesis of N,N‐disubstituted hydrazines via the electrocatalytic addition of hydrazine to α,β‐unsaturated carbonyl compounds is reported. The reaction was carried out under constant current electrolytic conditions in an undivided cell. Using this methodology, various N,N‐disubstituted hydrazines were prepared in 57–94% yield in 40 minutes. By adding cyclohexanone and acetic acid to the reaction mixture of N,N‐disubstituted hydrazines and heating for 2 hours, a one‐pot synthesis of N‐substituted indoles was also developed. Furthermore, based on cyclic voltammetry and control experiments, a plausible mechanism involving a radical pathway is proposed. [ABSTRACT FROM AUTHOR]

7-Bromo-4-chloro-1H-indazol-3-amine is a heterocyclic fragment used in the synthesis of Lenacapavir, a potent capsid inhibitor for the treatment of HIV-1 infections. In this manuscript, we describe a new approach to synthesizing 7-bromo-4-chloro-1H-indazol-3-amine from inexpensive 2,6-dichlorobenzonitrile. This synthetic method utilizes a two-step sequence including regioselective bromination and heterocycle formation with hydrazine to give the desired product in an overall isolated yield of 38–45%. The new protocol has been successfully demonstrated on hundred-gram scales without the need for column chromatography purification. This new synthesis provides a potential economical route to the large-scale production of this heterocyclic fragment of Lenacapavir. [ABSTRACT FROM AUTHOR]

Hierarchically architectured CoWO 4 /Ni x Fe y S microspheres with crystalline-amorphous interface showed multifunctional electrocatalysis in the application of water splitting and hydrazine sensing. [Display omitted] Highly efficient and multifunctional electrocatalysts are of high value in energy transformation and electrochemical sensing. Herein, hierarchically architectured cobalt tungstate/nickel iron sulfide (CoWO 4 /Ni x Fe y S) microspheres with a crystalline-amorphous interface have been prepared on bimetallic substrate of nickel–iron foam (NIF) by a two-step hydrothermal method. Electrochemical characterization shows that CoWO 4 /Ni x Fe y S microspheres can boost the electrocatalytic activity effectively through the synergistic effect on the crystalline-amorphous interface. When the CoWO 4 /Ni x Fe y S is applied as the electrocatalysts for oxygen evolution reaction (OER) and the hydrogen evolution reaction (HER), the overpotentials at a high current density of 500 mA cm−2 are only 322.8 mV and 306.5 mV, respectively. The overall water splitting device composed of CoWO 4 /Ni x Fe y S/NIF couple only needs a cell voltage of 1.80 V to reach a current density of 100 mA cm−2, and 2.19 V to reach 500 mA cm−2. The CoWO 4 /Ni x Fe y S/NIF can be also utilized as an effective electrochemical platform for the sensing of toxic hydrazine in a wide range from 50 μM to 17.3 mM, with a detection limit of 46.4 μM. All these results display that the CoWO 4 /Ni x Fe y S/NIF can be a high-performance multifunctional material for energy transformation and environmental pollutant monitoring. [ABSTRACT FROM AUTHOR]

Highly pure Rh2P nanoparticles on N,P-codoped carbon were synthesized by a simple ‘‘mix-and-pyrolyze’’ method using one kind of low-cost nucleotide as the carbon, nitrogen and phosphorus source, which exhibits excellent bifunctional activity for the hydrogen reduction and hydrazine oxidation reactions, achieving energy-efficient hydrogen production. [ABSTRACT FROM AUTHOR]

Satellite propulsion uses liquid mono or bi‐propellants composed of a hydrazine in combination with a strong oxidant. However, hydrazines are highly toxic. As a result, many research efforts for more environmentally compatible propellants have been made over the past decade. In this study we evidence green formulations that retain high propulsive performances. They are based on the dinitramide anion. From an initial library of 37 ammonium dinitramides 3 best candidates were selected after evaluation of their potential syntheses, calculated theoretical performances, experimental synthesis optimizations and decomposition temperatures. These three salts were then formulated to obtain acceptable sensitivities and melting points, which eventually led to only one formulation being retained: a 40 : 60 mixture of dimethylammonium dinitramide and ammonium dinitramide phlegmatized by 10 % of glycerol. [ABSTRACT FROM AUTHOR]

An iodophor-catalyzed direct disulfenylation of amino naphthalenes with aryl sulfonyl hydrazines in water was developed. A series of aryl sulfides were obtained in moderate to excellent yields. The advantages of this green protocol were the simple reaction conditions (metal-free, water as the solvent, under air), the odorless and easily available sulfur reagent, the broad substrate scope, and gram-scale synthesis. Moreover, the potential application of aryl sulfides was exemplified by further transformations. [ABSTRACT FROM AUTHOR]

This work investigates the electrocatalytic properties of carbon paste electrodes (CPEs) modified with ionic liquids (IL) and metallic ionic liquid (ILFe) for the hydrazine oxidation reaction (HzOR). The results indicate that ILFe significantly enhances the catalytic activity of the electrode, exhibiting catalysis towards hydrazine oxidation, reducing overpotential, and increasing reaction current. It is determined that the HzOR on the MWCNT/MO/ILFe electrode involves the transfer of four electrons, with high selectivity for nitrogen formation. Additionally, ILFe is observed to improve the wettability of the electrode surface, increasing its capacitance and reaction efficiency. This study highlights the advantages of ILFe-modified CPEs in terms of simplicity, cost-effectiveness, and improved performance for electrochemical applications, demonstrating how the ionic liquid catalyzes hydrazine oxidation despite its lower conductivity. [ABSTRACT FROM AUTHOR]

Thiocyanates form an important class of organic compounds commonly found in natural products that exhibit excellent antimicrobial activity. The electrophilic thiocyanation is one of the most effective methods of introducing a -SCN functional group to the parent organic molecule. In this work, we explored an eco-friendly and highly efficient method for thiocyanation of anilines and 1-(substituted benzylidene)-2-phenylhydrazines using commercially available N-bromoscuccinimide (NBS) and potassium thiocyanate (KSCN). The optimized protocol afforded thiocyanates with good regioselectivity and excellent yields in comparison to the available methods. [ABSTRACT FROM AUTHOR]

The reaction of equimolar quantities of 3-(1-(4-methoxyphenyl)-5-methyl-1H-1,2,3-triazol-4-yl)-1-phenyl-1H-pyrazole-4-carbaldehyde and (2,4,6-trichlorophenyl)hydrazine in ethanol containing concentrated hydrochloric acid (0.2 mL; 37%) as a catalyst under reflux for 2 h yielded 1-(1-(benzofuran-2-yl)ethylidene)-2-(2,4,6-trichlorophenyl)hydrazine. The crude produced was purified by crystallization using dimethylformamide to provide the title heterocycle in a 95% yield. The structure of the newly synthesized heterocycle was confirmed through X-ray diffraction and spectral analyses. [ABSTRACT FROM AUTHOR]

This work reports the development of novel curcuminoid-based electrochemical sensors for the detection of environmental pollutants from water. In this study, the first set of electrochemical experiments was carried out using curcumin-conjugated multi-walled carbon nanotubes (MWCNT–CM) for 1,4-dioxane detection. The MWCNT–CM/GCE showed good sensitivity (103.25 nA nM−1 cm−2 in the linear range 1 nM to 1 µM), with LOD of 35.71 pM and LOQ of 108.21 pM. The second set of electrochemical experiments was carried out with bisdemethoxy curcumin analog quantum dots (BDMCAQD) for hydrazine detection. The BDMCAQD/GCE exhibited good sensitivity (74.96 nA nM−1 cm−2 in the linear range 100 nM to 1 µM), with LOD of 10 nM and LOQ of 44.93 nM. Thus, this work will serve as a reference for the fabrication of metal-free electrochemical sensors using curcuminoids as the redox mediator for the enhanced detection of environmental pollutants. [ABSTRACT FROM AUTHOR]

The increasing utilization of hydrazine and its derivatives across diverse sectors highlights the pressing need for efficient detection methods to safeguard human health and the environment. Likewise, nicardipine, a widely used medication for heart diseases, necessitates accurate sensing techniques for clinical research and therapeutic monitoring. Here, we propose a novel approach using a naphthalimide-functionalized Zr-MOF as a fluorometric probe capable of detecting both hydrazine and nicardipine in aqueous medium. Our designed probe exhibited a significant 31-fold increase in fluorescence intensity upon interaction with hydrazine. At the same time, nicardipine induced 86% fluorescence quenching with an exceptionally rapid response time (100 s for hydrazine and 5 s for nicardipine). The designed probe has the ability to detect both analytes at nanomolar concentrations (LOD for hydrazine is 1.11 nM while that for nicardipine is 9.6 nM). Investigation across various wastewater samples and pH conditions further validated its practical utility. The mechanism behind fluorometric sensing of nicardipine was thoroughly investigated using modern instrumentation. Our study presents a versatile and effective approach for detecting hydrazine and nicardipine, addressing crucial needs in both industrial and biomedical contexts. [ABSTRACT FROM AUTHOR]

The new hydrazine 5H-dibenzo[b,f]azepin-5-amine (2) reacts with P- and Si-electrophiles via deprotonation to afford P(III)-, P(V)-, and TMS-hydrazides 3–8 and with carbonyl electrophiles via acid-free condensation to the N-substituted hydrazones 9–12 that are potential N-alkene ligands. While β-ketohydrazone 9 and α-dihydrazone 10 react with [Mes(Cu)]4, [Cu(NCCCH3)4]2PF6, and FeCl2(THF)1.5 to afford complexes devoid of alkene interaction, [Cu(OTf)]2·C6H6 reacts with the α-keto hydrazone 11 or with N,N dimethyl-hydrazone 12 to form the neutral dimeric Cu(I) complex 18 with bridging Cu(I)–alkene interactions or the tetrahedral cationic complex 19 in which 12 binds as a bidentate hydrazone-alkene ligand, respectively. The surprising stability of the alkene coordination in complexes 18 and 19 prevents substitutions with, e.g., PPh3. [ABSTRACT FROM AUTHOR]

Novel imidazopyridines hydrazine conjugates were designed and synthesized for their anti‐tubercular (anti‐TB) activity. A cytotoxicity assay was conducted with Vero cells to determine the safety profile of the most effective compounds. It was found that compound (IA3) (MIC=0.78 μM) and (IA8) (MIC=1.12 μM) were nearly 3.7 and 2.5 times more active than pyrazinamide. Based on Density functional theory (DFT), these molecules exhibited better charge transfer between molecular orbital's, which made them suitable for biological applications. Molecular docking on Mycobacterium tuberculosis InhA bound to NITD‐916 (PDB: 4R9S) revealed that compounds possessed greater binding affinity towards proteins. In addition, the most active anti‐TB compounds (IA3) and (IA8) exhibited high levels of interaction with the target protein and exceptional safety profile, suggesting they may prove to be effective leads for new drugs. [ABSTRACT FROM AUTHOR]

Herein, we present a comprehensive study on electrochemical hydrazine oxidation using hybrid material, MoS2-GO (molybdenum disulfide-graphene oxide), as an efficient electrocatalyst fabricated using the simple chemical reduction method. The MoS2-GO hybrid material adopts a distinctive open flower-like morphology, as demonstrated by field emission scanning electron microscopy (FE-SEM). Asymmetric and uneven distribution is indicated by energy dispersive X-ray spectroscopy (EDS), while UV–Vis investigation displays shifts in peak positions and intensities, signifying the successful formation of the MoS2-GO composite. Further supporting the composite's structure, X-ray diffraction (XRD) studies validate the hexagonal arrangement of MoS2 layers on the graphene oxide (GO) surface. Through a combination of material synthesis, characterizations, and electrochemical analyses, we demonstrate that the MoS2-GO hybrid exhibits a low overpotential ∼0.2 V versus SCE. This outstanding electrocatalytic performance of MoS2-GO underscores its potential as a promising candidate for various electrochemical applications, especially those involving hydrazine-based reactions. GO was used as the supporter and promoter by improving the synergetic effect between MoS2 and GO toward the hydrazine oxidation reaction. [ABSTRACT FROM AUTHOR]

A concise set of 4‐substituted pyrazolo[3,4‐d]pyrimidine carboriboside analogues was synthesized in a divergent fashion via a central intermediate. An oxaziridine reagent allowed the synthesis of a crucial hydrazine glycon intermediate, which was transformed through a base‐build‐up strategy into the desired intermediate using a commercially available pyrimidine building block. Reaction with a variety of nucleophiles allowed late‐stage diversification. All analogues were evaluated for activity against a representative panel of Trypanosomatida. A methoxy‐substituted analogue displayed single‐digit micromolar activity against two subspecies of Trypanosoma brucei in cellular assays. [ABSTRACT FROM AUTHOR]

2-Chloro-5-[(6-hydroxy-4,7-dimethoxy-1-benzofuran-5-yl)carbonyl]pyridine-3-carbonitrile (3) was synthesized and its chemical reactivity was investigated toward a diversity of binucleophiles. Treatment of compound 3 hydrazine hydrate and phenylhydrazine produced pyrazolo[3,4-b]pyridines while isoxazolo[5,4-b]pyridine was obtained from reacting compound 3 with hydroxylamine. A diversity of pyrido[2,3-d]pyrimidines was synthesized from treatment of staring substrate 3 with some 1,3-N,N-binucleophiles. Treating compound 3 with some 1,4-binucleophiles including ethylenediamine, o-phenylenediamine, 2-aminophenol and 2-aminothiophenol furnished pyrido[2,3-e][1,4]diazepine 12 and pyrido[2,3-b][1,5] benzodiazepine 13, pyrido[2,3-b][1,5]benzoxazepine 14 and pyrido[2,3-b][1,5] benzothiazepine 15, respectively. The synthesize compounds shown remarkable effect against yeast and fungus, while compounds 4 and 7–11 exhibit excellent efficacy against all types of Gram + and Gram - bacteria. Structures of the produced compounds were established using analytical and spectroscopic tools. [ABSTRACT FROM AUTHOR]

Hydrazine, a highly toxic compound, demands sensitive and selective detection methods. Building upon our previous studies with pre-coumarin OFF–ON sensors for fluoride anions, we extended our strategy to hydrazine sensing by adapting phenol protecting groups (propionate, levulinate, and γ-bromobutanoate) to our pre-coumarin scaffold. These probes reacted with hydrazine, yielding a fluorescent signal with low micromolar limits of detection. Mechanistic studies revealed that hydrazine deprotection may be outperformed by a retro-Knoevenagel reaction, where hydrazine acts as a nucleophile and a base yielding a fluorescent diimide compound (6,6′-((1E,1′E)-hydrazine-1,2diylidenebis(methaneylylidene))bis(3(diethylamino)phenol, 7). Additionally, our pre-coumarins unexpectedly reacted with primary amines, generating a fluorescent signal corresponding to phenol deprotection followed by cyclization and coumarin formation. The potential of compound 3 as a theranostic Turn-On coumarin precursor was also explored. We propose that its reaction with ALDOA produced a γ-lactam, blocking the catalytic nucleophilic amine in the enzyme's binding site. The cleavage of the ester group in compound 3 induced the formation of fluorescent coumarin 4. This fluorescent signal was proportional to ALDOA concentration, demonstrating the potential of compound 3 for future theranostic studies in vivo. [ABSTRACT FROM AUTHOR]

We have encountered a superbase‐mediated chemoselective reaction of N‐tosylhydrazones with aza‐ortho‐quinone methide precursors. When tosylhydrazone was treated with ortho‐aminobenzyl alcohol in super basic conditions (KOH+DMSO), we observed the formation of 2‐substituted quinoline. The reaction was found to be general, and by this method, mono‐, di‐ and tri‐substituted quinolines could be made. We could prove experimentally and theoretically that the reaction proceeded via the formation of an azine from the basic decomposition of N‐tosylhydrazones. Finally, the reaction of tosylhydrazone with N‐(2‐(chloromethyl)phenyl)‐4‐methylbenzenesulfonamide (aza‐ortho‐quinone methide precursor) under super basic conditions afforded hydrazine substituted sulfonamides. [ABSTRACT FROM AUTHOR]

The development of high‐purity and high‐energy‐density green hydrogen through water electrolysis holds immense promise, but issues such as electrocatalyst costs and power consumption have hampered its practical application. In this study, we present a promising solution to these challenges through the use of a high‐performance bifunctional electrocatalyst for energy‐efficient hydrogen production via coupled hydrazine degradation. The biphasic metal nitrides with highly lattice‐matched structures are deliberately constructed, forming an enhanced local electric field between the electron‐rich Ni3N and electron‐deficient Co3N. Additionally, Mn is introduced as an electric field engine to further activate electron redistribution. Our Mn@Ni3N‐Co3N/NF bifunctional electrocatalyst achieves industrial‐grade current densities of 500 mA cm−2 at 0.49 V without degradation, saving at least 53.3 % energy consumption compared to conventional alkaline water electrolysis. This work will stimulate the further development of metal nitride electrocatalysts and also provide new perspectives on low‐cost hydrogen production and environmental protection. [ABSTRACT FROM AUTHOR]

The novel chromonyltriazolo[3,4-b][1,3,4]thiadiazole derivative 5 was efficiently synthesized and utilized as key intermediate for construction of a diversity of heterocyclic rings; through reactions with binucleophilic reagents. Treating electron deficient substrate 5 with hydrazine hydrate, phenylhydrazine and hydroxylamine furnished pyrazolyl/isoxazolyltriazolo[3,4-b][1,3,4]thiadiazoles 6-8. Also, reacting substrate 5 with guanidine, cyanoguanidine and thiourea provided pyrimidinyltriazolo[3,4-b][1,3,4]thiadiazoles 9-11. Reaction of substrate 5 with ethylenediamine and o-phenylenediamine afforded diazepine derivatives 12 and 13. Reaction of substrate 5 with malononitrile, ethyl cyanoacetate and cyanoacetamide afforded pyrans 14, 15 and pyridine 16 linked triazolo[3,4-b][1,3,4]thiadiazolyl chromeno[2,3-b]pyridines. The anticancer efficiency of the current compounds presented diverse inhibitory action against certain cancer cell lines. On the basis of analytical and spectral findings, the structures of the synthesized products were confirmed. [ABSTRACT FROM AUTHOR]

Exposures to hydrazines occur during aeronautic and space operations and pose a potential risk to personnel. Historically, extensive preparatory countermeasures have been taken due to concern for severe toxicity. This study seeks to better understand manifestations of acute occupational exposures to hydrazine to guide recommendations for management. A retrospective database review of records from four United States regional poison centers was conducted of all human exposures to hydrazine, monomethylhydrazine, or 1,1-dimethylhydrazine over two decades. Following case abstraction, descriptive statistics were performed to characterize demographics, manifestations, treatments, and outcomes. One hundred and thirty-five cases were identified, and most were adult males exposed to inhaled hydrazine propellant vapors. Fifty-seven percent of patients were asymptomatic following exposure; otherwise, common symptoms were dyspnea, throat irritation, cough, ocular irritation, and headache. All patients were evacuated or received decontamination, with a few reports of symptomatic treatments, including oxygen supplementation and salbutamol (albuterol). Patients usually recovered quickly and were released after a brief healthcare facility evaluation or observed locally. No patients developed delayed symptoms. Symptoms of severe toxicity were not observed, and there were no deaths. Acute exposures to hydrazines during operations within the aerospace industry appear to be limited primarily to mucosal and mild pulmonary irritation without significant neurologic, hepatic, or hematologic toxicity. These findings are contrary to previously established expectations and may be related to low-level exposures or possibly due to current emergency countermeasures. Care in occupational hydrazine exposure will focus on evacuation, decontamination, and symptomatic management of chemical irritant properties of hydrazines. It is reasonable to manage mild cases outside of a healthcare facility. Continued endeavors in human space exploration and habitation will increase the risk of these exposures, making it imperative that clinicians be comfortable with the care and management of these patients. [ABSTRACT FROM AUTHOR]

The reaction of sulfonyl derivatives of 4-methylpyrazolo[5,1-c][1,2,4]triazines with N,N-dimethylformamide dimethyl acetal afforded a series of new enamines of pyrazolo-as-triazines. The synthesized compounds were studied in the reactions with some N-nucleophiles. It was found that the reaction of N,N-dimethylaminomethylene derivatives of 3-mesyl- and 3-tosylpyrazolo[5,1-c][1,2,4]triazines with hydrazine hydrate is accompanied by the as-triazine ring opening to give linear hydrazones, which was confirmed by X-ray diffraction data. [ABSTRACT FROM AUTHOR]

Hydrazine is considered a powerful reducing agent and catalyst, showing diverse applications in agricultural industries, toxic degradation research, and wastewater management. Additionally, hydrazine can trigger some specific reactions when combined with suitable oxidants. Due to its highly polar nature, hydrazine can easily dissolve in alcohol, water, and various other polar solvents. Therefore, it can be extensively utilized in different areas of application and industries such as rocketry and various chemical applications. Despite its beneficial properties, hydrazine is unstable, posing significant risk due to its highly toxic nature. It is extremely hazardous to both human health and the environment. It can cause various illnesses and symptoms such as dizziness, temporary blindness, damage to the central nervous system, and even death when inhaled in sufficient quantities. Therefore, it is highly important to monitor the level of hydrazine to prevent its toxic and hazardous effects on human beings and the environment. In the present study, we discuss the simple fabrication of a disposable cost-effective and eco-friendly hydrazine sensor. We used a screen-printed carbon electrode, i.e., SPCE, as a base for the construction of a hydrazine sensor. The Ti3AlC2 MAX has been used as a suitable and efficient electrode material for the fabrication of disposable hydrazine sensors. We modified the active surface of the SPCE using a drop-casting approach. The resulting Ti3AlC2 MAX modified SPCE (Ti3AlC2@SPCE) has been utilized as an efficient and low-cost hydrazine sensor. Cyclic voltammetry, i.e., CV, and linear sweep voltammetry, viz., LSV, was employed as a sensing technique in this study. The optimization of pH and electrode material loading was conducted. The Ti3AlC2@SPCE exhibited excellent sensing performance toward hydrazine oxidation. A reasonable detection limit (0.01 µM) was achieved for hydrazine sensing. The fabricated sensor also demonstrated a reasonable linear range of 1–50 µM. This work provides the design and fabrication of simple disposable Ti3AlC2@SPCE as a suitable electrode for the determination of hydrazine using LSV technology. [ABSTRACT FROM AUTHOR]

Sensitive and efficient detection of hydrazine is of great significance because hydrazine is a highly toxic organic molecule, which can pose great threats to human health. Herein, two covalent organic frameworks (COFs) modified with ester groups in the pores, TAPB‐DHE and TAPT‐DHE, have been successfully synthesized via esterification reaction. Both of the two COFs have good crystallinity, thermal stability, and fluorescence properties. TAPB‐DHE can be used as a turn‐on fluorescence sensor for the sensitive detection of trace hydrazine in aqueous solution with a detection limit of 0.40 μM and a wide linear range of 0–100 μM due to the fluorescence enhancement of TAPB‐DHE caused by the chemical reaction between hydrazine and TAPB‐DHE, in which the ester group of the COF is converted into hydroxyl group, leading to the restriction of the intramolecular charge transfer (ICT) effect. This work provides a reference for the design of COFs with hydrazine recognition function and a helpful expansion for the practical application of COFs. [ABSTRACT FROM AUTHOR]

We have simulated two mechanisms, direct and superexchange, for the electron transfer in a model Bis(hydrazine) Radical Cation, which consists of two hydrazine moieties coupled by a benzene ring. The computations, that are inspired by the attochemistry approach, focus on the electron dynamics arising from a coherent superposition of four cationic states. The electron dynamics, originating from a solution of the time dependent Schrödinger equation within the Ehrenfest method, is coupled to the relaxation of the nuclei. Both direct (ca. 15 fs dynamics) and superexchange (ca. 2 fs dynamics) mechanisms are observed and turn out to lie on a continuum depending on the strength of the coupling of the benzene bridge electron dynamics with the hydrazine chromophore dynamics. This contrasts with the chemical pathway approach where the direct mechanism is completely non-adiabatic via a conical intersection, while the superexchange mechanism involves an intermediate radical with the unpaired electron localized on the benzene ring. Thus, with the attochemistry-inspired electron dynamics approach, one can distinguish direct from superexchange mechanisms depending on the strength of the coupling of two types of electron dynamics: the slow hydrazine dynamics (ca. 15 fs) and the fast benzene linker dynamics (ca. 2 fs). In this model bis(hydrazine) radical cation, only when the intermediate coupler is in an anti-quinoid state, does one see the coupling of the bridge and hydrazine chromophore dynamics. [ABSTRACT FROM AUTHOR]

A light-induced method is developed for synthesizing azauracils. This method is independent from traditional methodology. Remarkably, this reaction can also be powered by sunlight. The applicability of this method is further demonstrated through its successful implementation in large-scale reactions and its use in synthesizing derivatives. [ABSTRACT FROM AUTHOR]

Water-splitting coupled with the hydrazine oxidation reaction (HzOR) is a remarkably important strategy for H2 production, but remains a challenge. Herein, a Fe-doped Ni2P-Co2P-Zn3P2 heterogeneous electrocatalyst with a nanoneedle-assembled nanosphere structure and abundant defects was fabricated on Ni foam (Fe-NiCoZnP/NF). The introduction of Fe can tune the electron structure of NiCoZnP/NF, leading to a modulation of the d-band center towards the Fermi level, hence optimizing the free energy of hydrogen (ΔGH*) and dehydrogenation behavior of hydrazine, and thereby realizing splendid HER and HzOR activities. The fabricated Fe-NiCoZnP/NF catalyst displays outstanding HER and HzOR activity and durability, with potentials of 121 and 13 mV vs. RHE to drive 1000 mA cm-2 and Tafel slopes of 31.2 and 11.9 mV dec-1, respectively, and a long durability of 120 h to achieve 100 mA cm-2. Impressively, overall water-hydrazine electrolysis employing Fe-NiCoZnP/NF as the anodic and cathodic electrodes only requires low voltages of 1.92 and 2.67 V to achieve 100 and 1000 mA cm-2, respectively, with a high stability for 120 h operation time during overall hydrazine splitting (OHzS). This work offers a justification for the design of high-efficiency bifunctional catalysts, and promotes energy-saving industry-level hydrogen generation. [ABSTRACT FROM AUTHOR]

By introducing more polar ethanol as a co-solvent to benzene, solvent effects on gelation behavior and gel properties of N,N'-bis (4-n-alkylo-xybenzoyl) hydrazine (4D16) were investigated herein. Xerogel of 4D16 showed fiber networks in benzene, while slice aggregates in benzene/ethanol mixtures and precipitates of 4D16 in ethanol showed rod-like aggregates. XRD patterns revealed that the aggregation structure of 4D16 translated from cubic phase to lamellar phase gradually with the increase of ethanol content. FT-IR spectra showed that the H-bonding of 4D16 showing lamellar phase was stronger than that in cubic phase. Kinetics of gelation 4D16 of showed that Dfvalue of the aggregates increased firstly and decreased afterwards (1.204→1.522→1.244). Organogel in benzene/ethanol mixtures showed higher thermostability (Tgel) and mechanic properties with the increase of ethanol content. [ABSTRACT FROM AUTHOR]

A novel inorganic-monosaccharide nanohybrid synthesized through coating the nickel–zinc ferrite (NZF) core by silica and subsequent functionalization with galactose (Ni0.4Zn0.6Fe2O4@SiO2/galactose) and characterized by FT-IR, FESEM, EDAX, XRD, XRF, BET, TGA, and VSM techniques. Its catalytic efficacy examined in some domino four-component reactions to obtain various classes of phthalazine derivatives at 90 °C under solvent-free conditions: (i) the reaction of phthalic anhydride (PA), hydrazine hydrate, dimedone, and different aldehydes to get 3,3-dimethyl-13-(aryl)-3,4-dihydro-1H-indazolo[1,2-b]phthalazine-1,6,11(2H,13H)-triones; (ii) the reaction of phthalic anhydride/phthalimide, hydrazine hydrate, malononitrile, and different aldehydes to obtain 3-amino-5,10-dioxo-1-(aryl)-5,10-dihydro-1H-pyrazolo[1,2-b]phthalazine-2-carbonitriles; and (iii) the reaction of succinic anhydride, hydrazine hydrate, dimedone, and different aldehydes to prepare 3,3-dimethyl-11-(aryl)-3,4,7,8-tetrahydro-1H-pyridazino[1,2-a]indazole-1,6,9(2H,11H)-triones. In addition, the recovery and reusability of the Ni0.4Zn0.6Fe2O4@SiO2/galactose determined successfully, and the reused nanocomposite identified through FESEM and EDAX techniques. [ABSTRACT FROM AUTHOR]

The reaction of acetyl-containing furan-3-carboxylates with substituted hydrazines in an alcohol solution leads to the formation of substituted furan-3-carboxylate hydrazones. The resulting hydrazones have E-configuration, as determined by NMR spectroscopy and X-ray diffraction analysis. [ABSTRACT FROM AUTHOR]

The reaction of 1-(3-(furan-2-yl)-5-methyl-1-(4-nitrophenyl)-1H-pyrazol-4-yl)ethan-1-one 1 with dimethylformamide dimethyl acetal (DMF-DMA) afforded 3-(dimethylamino)-1-(3-(furan-2-yl)-5-methyl-1-(4-nitrophenyl)-1H-pyrazol-4-yl)prop-2-en-1-one 2. Then the treatment of enaminone 2 with the appropriate hydrazonoyl halides 3a–f in chloroform in the presence of triethylamine at reflux gave novel bipyrazolyl methanone derivatives 4a–f. The novel bipyrazole derivatives 4a–c and 4d–f reacted with hydrazine hydrate in ethanol at reflux to give the corresponding pyrazolopyridazinones 9a–c and pyrazolopyridazines 10d–f, respectively. Stirring of hydroximoyl chlorides 11a,b with enaminone 2 in chloroform in the presence of triethylamine at room temperature afforded isoxazole derivatives 12a,b. The reaction of isoxazoles 12a,b with hydrazine hydrate in refluxing ethanol gave the corresponding isoxazolopyridazines 14a,b. [ABSTRACT FROM AUTHOR]

Background: The production of a variety of chalcones (1-Aryl/Alkyl amino substituted-dene-2-(-1,3-diphenylallylidene) hydrazine (ABSa-e) was brought about as a result of the condensation of hydrazide compound and Aryl/Alkyl substituted aldehyde/ketone in ethanol as a solvent with the help of two drops of conc. hydrochloric acid as a catalyst followed by neutralization. All synthesized derivatives were identified with different spectroscopic techniques and biologically evaluated by microorganisms. Materials and Methods: The in vitro antibacterial and antifungal activity of all synthesised compounds was evaluated. In the microbial studies, the five strains of selected bacteria and two strains of fungi have been used to evaluate the synthesized compounds, DMSO used as the solvent, and amoxicillin and griseofulvin used as control drugs. Results and Conclusion: Derivatives exhibited the highest potency (17mm, 18mm, 16mm, 18mm, 15mm) (MIC) with the electron donating groups (CH3) in position 4 of the phenyl ring (ABSc). On the other hand, the withdrawing group (NO2, Cl) of compounds ABSb & ABSe showed the most negligible potency against selected microorganisms. The unsubstituted phenyl ring (ABSa) showed moderate activity (17mm, 15mm, 15mm, 16mm, 14mm) at 100 µg/mL. The oxygen-containing furan compound ABSd proved as the second-highest potency (16mm, 17mm, 15mm, 17mm, 14mm) of this series. All of the results pointed to compound ABSc as a potential antibacterial lead molecule, and efforts are currently being made to increase the potency of amino chalcone derivatives. [ABSTRACT FROM AUTHOR]

Hydrazine‐assisted water electrolyzer is a promising energy‐efficient alternative to conventional water electrolyzer, offering an appealing path for sustainable hydrogen (H2) production with reduced energy consumption. However, such electrolyzer is presently impeded by lacking an efficient catalyst to accelerate the kinetics of pivotal half‐reaction, that is, hydrazine oxidation reaction (HzOR). Herein, a ruthenium (Ru) single‐atom on an octahedral cobalt oxide (Co3O4) substrate (Ru‐Co3O4) catalyst, guided by theoretical calculations is developed. Those lattice‐confined Ru sites within octahedral structure of spinel Co3O4 effectively lower the energy barrier required for the formation of N2H2* intermediate and desorption of H* species in HzOR. As a result, the Ru‐Co3O4 catalyst achieves superior HzOR performance with a low potential of −0.024 V versus (vs.)reversible hydrogen electrode (RHE) at 100 mA cm−2 and remarkable stability for over 200 h at 200 mA cm−2. Importantly, a modular H2 production achieves an output of 0.48 kWh electricity per m3 H2 by decoupling and pairing the HzOR and hydrogen evolution reaction (HER) half‐reaction with a Zinc (Zn) redox reservoir. The work represents a significant advancement in the field, offering substantial flexibility for on‐demand H2 production and energy output. [ABSTRACT FROM AUTHOR]

Improving the dispersion of metal nanoparticles and suppressing metal aggregation have long been the keys to constructing efficient metal-loaded catalysts. Herein, catalysts of cobalt (Co) supported on nitrogen (N)-doped carbon were prepared by a simple hydrothermal method using folic acid (FA) as the carbon source. Surprisingly, hydrazine hydrate not only facilitated the loading of metal Co, but also regulated the morphology of the catalyst, promoted the uniform distribution of metal Co, and effectively improved the catalytic hydrogenation activity of the catalyst. It was found that the catalyst mediated with 10 mL hydrazine hydrate and pyrolyzed at 900 °C exhibited the best catalytic performance (99.6% conversion of quinoline and 98.0% selectivity for 1,2,3,4-tetrahydroquinoline). In addition, it exhibited satisfying adaptability for diverse substrates. This study can provide great theoretical significance and practical guidance for the preparation of Co–N–C catalysts. [ABSTRACT FROM AUTHOR]

In organic synthesis, azodicarboxylates are frequently used as an aza‐dienophile and electrophilic amination agent. To create carbon–nitrogen bonds, azodicarboxylates typically react with nucleophiles or radicals. This report explores its reactivity as a co‐monomer towards radical polymerization to introduce nitrogen–nitrogen single bonds into the polymer chain. Azodicarboxylates are capable of copolymerizing with styrenic monomers to achieve linear polymers with 40% feed. [ABSTRACT FROM AUTHOR]

Azines are organic molecules with a C=N−N=C functional range of applications. But the conventional azines synthesis process requires a high reaction temperature and long reaction time combined with complex reaction facilities, so the synthesis process needs to be further improved in terms of economic efficiency and process simplification. Here, we demonstrate a structurally well‐defined inorganic ligand Ni compound, (NH4)4[NiMo6O18(OH)6](Ni‐POMs). The catalysts show good activity towards the reaction of carbonyl compounds, and the corresponding products can be obtained in yields up to about 90 %. In this condition, the majority of the aldehydes (aromatic and aliphatic) can be reacted, and the products are obtained in high yields. Density functional theory (DFT) looked into the process by which benzaldehyde and hydrazine hydrate reacted on the surface of Ni‐POMs. It was calculated that the whole reaction goes through two stages and the activation energy of the whole reaction is −6.72 kcal/mol. Thus, from experiment to calculation, a complete structure of the catalytic reaction cycle has been constructed. [ABSTRACT FROM AUTHOR]