Simple Pd/C-catalyzed reduction of nitroarenes with hydrazine hydrate in magnetized distilled water at room temperature

ABSTRACT Direct synthesis of a new series of pyrido[2,3‐ d ]pyrimidines and pyrido[2′,3′:3,4]pyrazolo[1,5‐ a ]pyrimidine s via heterocyclization of α‐aminonicotinonitrile was described and fully characterized. The desired pyrido[2,3‐ d ]pyrimidines 2‐7 were synthesized via acylation of α‐aminonicotinonitrile with formamide, acetic anhydride, and formic acid or addition cyclization reaction with phenyl isocyanate, ammonium thiocyanate, and urea, respectively. On the other hand, nicotinonitrile 1 was annulated with hydrazine hydrate, followed by cyclization with acetyl acetone and ethyl cyanoacetate to afford pyrido[2',3':3,4]pyrazolo[1,5‐ a ]pyrimidines 9 and 10 , respectively. All compounds were subjected to cytotoxicity screening against three cancer cell lines: HepG‐2, HCT‐116, and MCF‐7. The most cytotoxic compound, 3 , was subjected to PIM‐1 kinase inhibition and molecular docking to elucidate the virtual binding mechanism with the target. Interestingly, compound 3 demonstrates the most promising cytotoxicity with IC 50 values of 7.67 ± 0.4 µM (HepG‐2), 8.07 ± 0.6 µM (HCT‐116), and 6.90 ± 0.3 µM (MCF‐7), approaching the efficacy of DOX and sorafenib. Compound 3 showed a promising PIM‐1 kinase inhibition with an IC 50 of 0.03 µM, compared to Staurosporine, which had an IC 50 of 0.02 µM. PIM‐1 kinase inhibition was virtually visualized by molecular docking, which highlighted the binding interactions of the lead 3 with the PIM‐1 active site. Accordingly, compound 3 was validated as a PIM‐1‐targeted anti‐cancer agent.

High-performance decomposition of hydrazine hydrate to H2 under mild conditions over mechanochemically-synthesized NiO/La2O3 catalysts

A series of 5,6-diaryl-[1,2,3,4]-tetrazines 4 have been obtained by microwave irradiation followed by the basification of their dihydroiodides 3 with dilute ammonium hydroxide solution. These compounds were synthesized also by conventional heating for comparison. The latter were synthesized by the oxidative cyclization of 1,2-diaryl-2-hydrazino-ethylidine amines 2 using ethanolic iodine. The parent compounds 2 were prepared by refluxing the mixtures of substituted benzils 1 and hydrazine hydrate in n-propanol for 60 hr. Compounds 4 on acylation with acetic anhydride in 1:2 ratio afforded 2,3-diacetyl derivatives 5 and on reaction with sodium nitrite in 1:2 ratio in acidic medium afforded 2,5-dinitroso derivatives 6. The structures of synthesized compounds were established on the basis of chemical transformation, elemental analysis, IR,1H-NMR and Mass spectral studies. The title compounds have been assayed for their antimicrobial activity against gram-positive as well as gramnegative microorganisms.

Azofuranone was transformed into a series of pyrazole-based hydrazones with 71–79% yields through hydrazinolysis using hydrazine hydrate at room temperature followed by condensation with selected aromatic aldehydes in refluxing ethanol. The antiproliferative activity of the obtained derivatives was evaluated against MCF-7 (breast) and HCT-116 (colon) cancer cell lines using the MTT assay. Among the tested compounds, the chlorobenzylidene derivative (3a) exhibited the most pronounced cytotoxic activity (IC50 = 6.33 ± 1.3 µM against HCT-116 and IC50 = 8.61 ± 1.6 µM against MCF-7), while the remaining hydrazones also showed moderate to strong effects in both cell models. Computational target predictions suggested possible involvement of kinase-related pathways. Molecular docking studies were performed using CDK2 (PDB ID: 2 A4L) to explore potential binding modes. Compound 3a displayed a favorable docking score compared with the reference ligands and formed hydrogen-bond interactions with key residues within the active site. Molecular dynamics simulations indicated stable ligand–protein interaction patterns over the simulation period. In addition, in silico ADME analysis revealed acceptable physicochemical and pharmacokinetic characteristics, with compound 3a demonstrating the most balanced profile. Overall, the combined biological and computational findings identify compound 3a as a promising scaffold for further optimization in the development of antiproliferative agents.

The study aimed to design the series of azobenzene-induced 5-oxoimidazoline moiety, represents as a promising structural framework for the development of a new class of antimicrobial agents, supported by molecular docking studies. Two series of compounds (10 in each series) were synthesized through a multistep procedure beginning with diazotization of 2-nitroaniline, followed by coupling with methyl paraben to yield azobenzene compound (9), which were subsequently refluxed with hydrazine hydrate to afford the hydrazide intermediate (11). Reaction of compound (11) with substituted acetophenones 12(A1-A5) and aldehydes 12(A6-A10) produced schiff bases 13(S1-S10), which upon refluxing with amino acids (glycine and alanine) furnished the desired final compounds 14(M1-M10)and 15(M1-M10). The compounds were screened for in-vitro antimicrobial activity & molecular docking studies were carried out to investigate ligand - protein interactions and to predict the most probable binding conformations. Compounds 14M6 (MIC = 0.55 & 0.45 µg/ml, ΔG = -6.093), 14M9 (MIC = 0.38 µg/ml, ΔG = -5.928), 15M9 (MIC = 0.40 µg/ml, ΔG = -6.084) showed best anti-fungal activity displaying best docking score (PDB ID: 3LD6). The most active anti-bacterial compounds included 14M8 (MIC = 0.70 & 0.88 µg/ml, ΔG = -5.832), 14M9 (MIC = 0.54, 0.72& 0.39 µg/ml, ΔG = -5.755 & -5.845), 15M8 (MIC = 0.34, 0.75& 0.55 µg/ml, ΔG = -5.683 &-5.894), 15M9 (MIC = 0.65& 0.44 µg/ml, ΔG = -5.573) with best docking score (PDB ID: 2XCT & 6M1S). Compounds 14M6, 14M8, 14M9, 15M8 & 15M9 emerged as the most promising antimicrobial candidates, establishing them as potential lead molecules for further optimization and drug development.

Herein, a simple and efficient method is described for the one-pot multicomponent click synthesis of pyrazole-based derivative (APC) using hydrazine hydrate, malononitrile, ethyl acetoacetate and 9-anthracenecarboxaldhyde. An efficient fluorescence quenching probe was then developed for the rapid determination of thiamin hydrochloride (THC) with high sensitivity and selectivity. Firstly, the fluorescence quenching experiment was carried out at different pH values, that are 1, 3, 5, 7, 9, 11 and 13. It was found that the fluorescence quenching efficiency response was maximum at neutral pH (pH = 7). The designed protocol afforded impressive fluorescence quenching results, offering a lower limit of detection of 2.55 μM, in the linear range of 1–25 μM. Additionally, the calculated value of the quenching constant or stern-Volmer constant was noted to be 1.823 × 104 M−1 or 0.01823 µM, depicting appreciable fluorescent quenching response. In order to get mechanistic insights of detection, the FT-IR, MS and 1H NMR titrations were conducted. The obtained results indicated that Photoinduced Electron Transfer (PET) phenomena was responsible for desired detection. Furthermore, the method was successfully applied for the quantification of Vitamin B1 in various kinds of real milk samples. The developed protocol afforded excellent recovery rates, ranging from 98.991 to 103.091%, for the real samples analysis test. Moreover, the selectivity test was also performed in order to check the applicability of the designed protocol toward targeted analyte. It has been depicted that the designed sensor offered noteworthy quenching efficiency, having a value of 92.8% for THC determination. Moreover, the greenness of the method has also been checked using AGREE software. The designed assay was quite simple, accurate, and less time-consuming with appreciable results that can be used for routine analysis and detection of thiamin hydrochloride.

ABSTRACT Diabetes mellitus (DM) is a group of metabolic diseases characterized by long term high blood sugar levels. This work reports the synthesis of a hydrazone Schiff base compounds based on furan‐2‐carboxylic acid by treating sulfuric acid with the starting material (furan‐2‐carboxylic acid) in ethanol solvent to get the esterified compounds. Hydrazine hydrate was then refluxed with the desired ester in ethanol solvent to get the hydrazide, which was further refluxed with 4‐fluorobenzaldehyde in ethanol containing a catalytic amount of acetic acid to get the hydrazone compound. The compound has been characterized and assessed for their in vitro α‐amylase, α‐glucosidase, antioxidant, and dipeptidyl peptidase‐IV inhibition followed by in vivo antidiabetic activity. The biological studies of the compound showed significant α‐amylase (IC 50 = 47.11) and α‐glucosidase (IC 50 = 25.91) activities superior than the standard acarbose. The compound attributed significant dipeptidyl peptidase‐IV inhibition, and also notable antioxidant potential. Furthermore, on the basis of in vitro findings this compound showed a substantial reduction of in blood glucose level in animal model and no toxicity was observed in animal model and improvement in biochemical parameters. Furthermore, the molecular docking study showed that the compound has highest binding energy with α‐amylase (−6.5) and α‐glucosidase (−6.5). Additionally, ADME analysis was performed which indicated the compound pass all rules of drug and also have high GI absorption. The synthesized compound predicted bioavailable score was high. Simulation was done for further investigation of acarbose (control) and compound 3 which result show that compound 3 is more stable as compared acarbose.

Active and stable Ni-Cu-Mo ternary alloy catalyst for hydrogen generation from hydrazine hydrate

Abstract In this study, tri-metallic Ni@PdCu nanowires with a low Pd content and core-shell architecture were successfully synthesized via a two-step process in a polyol medium. Initially, Ni nanowires were fabricated by reducing Ni 2+ in ethylene glycol (EG) using hydrazine hydrate (N 2 H 4 ) as the reducing agent and polyvinylpyrrolidone (PVP) as the surfactant. Subsequently, a bimetallic PdCu shell was deposited onto the Ni nanowire surface through a galvanic replacement reaction, facilitated by microwave pulse irradiation (10 s on / 10 s off) in EG. The structural and morphological features of the resulting nanowires were characterized using X-ray diffraction (XRD), energy-dispersive X-ray spectroscopy (EDX), and transmission electron microscopy (TEM). When supported on Vulcan XC-72 carbon, the Ni@PdCu/C catalyst exhibited excellent electrocatalytic activity for the hydrogen evolution reaction (HER) in alkaline media. Electrochemical performance was assessed through cyclic voltammetry (CV), linear sweep voltammetry (LSV), and electrochemical surface area (ECSA) analyses, all conducted within a standard three-electrode system. The optimal catalyst, synthesized at 100 °C with a Ni:Pd:Cu molar ratio of 8:1:1, demonstrated a low overpotential, high exchange current density, and a favorable Tafel slope. Moreover, durability tests and comparative evaluations across acidic, neutral, and alkaline environments identified 1 M KOH as the most effective electrolyte, offering the best balance between catalytic activity and long-term stability. These findings underscore the synergistic interactions within the Ni-Pd-Cu system and its promise as a cost-effective and efficient electrocatalyst for hydrogen production in alkaline conditions.

Polychloroethenes—vinylidene chloride, 1,2-dichloroethene, trichloroethene, and tetrachloroethene—in reaction with tellurium activated in the hydrazine hydrate–KOH system form diethyl ditelluride. A multicomponent reaction of dichloroethenes and dichloromethane with tellurium affords 1,3-ditellurole in 30% yield.

Several linear and macrocyclic pentapeptide derivatives have been produced by coupling Nα-isophthalic acid 1 or Nα-isophthaloyl dichloride 2 with the appropriate sarcosine methyl esters. The corresponding Nα-isophthaloyl Sarcosyl-Sarcosine methyl ester 3 was developed by mixing 1 or 2 with sarcosine methyl ester. By hydrolyzing this with methanolic sodium hydroxide, the corresponding acid 4 was subsequently obtained. The corresponding tetrapeptide esters, Nα -isophthaloyl-bis-[Sarcosyl-Glycine ethyl ester], 5 and Nα -isophthaloyl-bis-[Sarcosyl -L-Phenylalanine methyl ester], 6, were developed by coupling the latter product 4 with another molecule of glycine ethyl ester or L-phenylalanine methyl ester. These compounds were subsequently hydrolyzed with methanolic sodium hydroxide to develop the corresponding acids, Nα-isophthaloyl-bis-[Sarcosyl–Glycine], 7 and Nα-isophthaloyl-bis-[Sarcosyl - L-Phenylalanine], 8. The corresponding cyclic pentapeptide methyl esters, Cyclo-(Nα-isophthaloyl)-bis-[Sarcosyl - Glycine]-L–Lys-(OMe), 9 and Cyclo-(Nα-isophthaloyl)-bis-[Sarcosyl-L-phenyl alanine]-L–Lys-(OMe), 10, were obtained by cyclizing tetrapeptide acids with L-lysine methyl ester. Finally, the corresponding acids Cyclo-(Nα-isophthaloyl)-bis-[Sarcosyl-Glycine]-L–Lys-(OH), 11 and Cyclo-(Nα-isophthaloyl)-bis-[Sarcosyl-L-phenyl alanine]-L–Lys-(OH), 12, were obtained by hydrolyzing methyl esters 9 and 10 with 1 N methanolic sodium hydroxide or hydrazinolyzing them with hydrazine hydrate to produce the cyclohydrazide compounds, Cyclo-(Nα-isophthaloyl)-bis-[Sarcosyl-Glycine]-L–Lys-(NHNH2), 13 and Cyclo-(Nα-isophthaloyl)-bis-[Sarcosyl-L-phenyl alanine]-L–Lys-(NHNH2), 14. KEY WORDS: Amino acids, Linear peptides, Macrocyclic pentapeptides, Nα-isophthaloyl dichloride, Sarcosine Bull. Chem. Soc. Ethiop. 2026, 40(3), 667-678. DOI: https://dx.doi.org/10.4314/bcse.v40i3.13

Pyranopyrazole derivatives are important heterocyclic scaffolds known for diverse pharmacological and industrial applications. However, conventional methods for their synthesis often require toxic reagents, harsh reaction conditions, and extended reaction times, creating environmental and operational concerns. Developing green, efficient, and sustainable synthetic methodologies for these derivatives remains a significant need in heterocyclic and medicinal chemistry. We developed an efficient, one-pot multicomponent reaction (MCR) protocol for synthesizing pyranopyrazole derivatives using glutamic acid as a biodegradable, non-toxic, and recyclable catalyst under solvent-free conditions at room temperature. The reaction involves the condensation of ethyl acetoacetate, aromatic or heteroaromatic aldehydes, hydrazine hydrate, and malononitrile, enabling rapid and high-yield synthesis. The methodology provided the desired pyranopyrazole derivatives in excellent yields (91–94%) within short reaction times. We systematically evaluated the effects of catalyst loading, solvent variation, and catalyst recyclability, demonstrating that glutamic acid can be reused for at least five cycles with minimal loss in activity. All synthesized compounds were characterized using NMR and FTIR spectroscopy, confirming the successful formation of target structures. A plausible reaction mechanism was proposed based on literature precedents and experimental observations. This green and efficient protocol offers operational simplicity, high atom economy, a straightforward workup, and an environmentally friendly profile, aligning with green chemistry principles. The methodology provides a practical and sustainable approach for the rapid synthesis of pyranopyrazole derivatives, expanding synthetic strategies for heterocyclic compounds with potential medicinal and material applications.

An efficient CuFe2O4 nanocatalyst was created using the simple and cost-effective assisted sol gel method, which has been effectively worked with as an efficient catalyst for one-pot multicomponent synthesis of pyrano[2,3-c] pyrazoles starting from aromatic aldehydes, malononitrile, ethyl acetoacetate, and hydrazine hydrate. The synthesized catalyst was characterized by using Fourier transform infrared (FT-IR), X-ray diffraction (XRD), energy dispersive X-ray (EDX), scanning electron microscopy (SEM), and transmission electron microscope (TEM) techniques.. The synthesized organic compounds were examined using IR, 1H NMR, and 13C NMR spectroscopy. The yield of pyrano[2,3-c] pyrazoles was studied using various reaction parameters such as the amount of catalyst, type of solvent, reaction conditions, and time. The present work's significant advantages such as simple setup, mild reaction conditions, non-toxic solvents, high yields, simple purification, efficiency, and utilization of recovered materials after four cycles.

ABSTRACT Mesoporous MCM‐41 serves as an ideal support due to its large surface area, ordered pore structure, and thermal resilience. Nickel (II) stands out among transition metals for its abundance, low cost, and adaptable coordination chemistry, making it suitable for immobilization via Schiff base ligands to drive various organic transformations. Motivated by these factors, we prepared a novel MCM‐41‐supported Ni (II) Schiff base catalyst, designated as M41@CP@AnL@Ni ( 1 ). The catalyst 1 was characterized by various techniques and tested for the formation of tetrahydropyrazolopyridines. The synthesis of tetrahydropyrazolopyridines was carried out in a single vessel by combining ethyl acetoacetate, hydrazine hydrate, an aromatic aldehyde, and ammonium acetate under mild conditions. The catalyst 1 demonstrated good catalytic performance and selectivity, afforded product yields of up to 97%, especially with electron‐deficient aryl aldehydes under mild thermal conditions (80 °C). The insignificant metal leaching and the absence of any measurable decline in the activity underscore its operational robustness and superior applicability relative to conventional catalytic systems. A feasible reaction mechanism has been proposed. These findings, in conjunction with the catalyst's observed efficiency, provide strong experimental support for the proposed pathway and highlight the critical involvement of the Ni (II) active site throughout the catalytic cycle.

Corrigendum to “An innovative design of hydrazine hydrate electrochemical sensor based on decoration of crown ether/Nafion/carbon nanotubes composite with gold nanoparticles” [J. Electroanal. Chem. 888 (2021) 115165

Chalcones are conjugated 1,3-unsaturated ketones that have a variety of pharmacological properties, such as antidiabetic, antioxidant and anticancer actions. Current study showed that, a chalcone, (E)-1,3-diphenylprop-2-en-1-one (1) was synthesized by reacting benzaldehyde with acetophenone. This compound was subsequently added with hydrazine hydrate and hydrazine hydrate in the attendance of acetic acid to yield two pyrazole derivatives, namely 3,5-diphenyl-4,5-dihydro-1H-pyrazole (2) and 1-(3,5-diphenyl-4,5-dihydropyrazol-1-yl) ethanone (3). The synthesized compounds were characterized using FTIR and 1H NMR spectroscopy. Compounds 1 to 3 demonstrated significant cytotoxic activity against the HeLa cell line. Additionally, they exhibited notable antioxidant properties. In silico studies were performed to evaluate the drug-likeness, pharmacokinetic profiles and molecular docking interconnections with the epidermal growth factor receptor (EGFR). These computational analyses provided insights into the potentiality of the compounds for drug-receptor binding and their pharmacokinetic behaviors. This work reports, for the first time, the comparative biological and computational studies conducted here. However, further detailed investigations are required to fully understand their mechanisms of action. Bangladesh Pharmaceutical Journal 29(1): 27-39, 2026 (January)

The title carbazole derivative, C14H11N3, was prepared by reacting 1-hy-droxy-8-methyl-9H-carbazole-2-carbaldehyde with hydrazine hydrate. In the solid state, the fused-ring system is slightly puckered, the dihedral angle between the planes of the outer rings being 2.24 (7)°. In the crystal, mol-ecules are linked by {N-H}2⋯N hy-dro-gen bonds to generate [010] chains, and weak C-H⋯π contacts consolidate the structure. A Hirshfeld surface analysis indicates that the most important contributions to the crystal packing are from H⋯H (43.1%), C⋯H/H⋯C (36.8%) and N⋯H/H⋯N (15.3%) inter-actions.

Wound healing is a complex process essential for maintaining skin integrity; however, the rise of antibiotic-resistant bacteria limits therapeutic options, highlighting the critical need for new antimicrobial agents. In this context, this research focused on the synthesis of new azole derivatives and their biological evaluation, specifically targeting antimicrobial, antioxidant, and biocompatible properties relevant to wound infections. In the present work, ketoconazole derivatives were obtained through an initial reaction with an excess of hydrazine hydrate, followed by condensation with benzaldehydes and cyclization with chloroacetyl chloride to form a β-lactam ring. These compounds were evaluated in vitro for antioxidant activity using FRAP, DPPH, and TAC assays, and for antimicrobial activity against a variety of microorganisms. Additionally, the cytotoxicity was assessed using the MTT assay on a normal mouse fibroblast cell line (NCTC, clone L929) for evaluating the biocompatibility of the obtained compounds. Derivative K1 exhibited the highest antioxidant activity, a finding confirmed by all three assays. Regarding antimicrobial properties, all compounds demonstrated notable activity, with K1, K4 and K5 displaying superior efficacy. Significantly, the MTT assay revealed that the derivatives exhibit dose-dependent cytotoxicity but maintain favorable safety profiles at therapeutic concentrations, supporting their suitability for topical application. In conclusion, these findings suggest that the synthesized derivatives may serve as promising leads for infected wound therapy. Future research will further explore the therapeutical potential of these compounds, together with their incorporation into polymeric films designed for chronic wound treatment.

Chlorothiopyrimidine 1 reacted with hydrazine hydrate and/or ethoxymethylene malononitrile, respectively, to form the corresponding starting material, amino cyano derivative 3. Compound 3 produced the amino pyrazolopyrazole derivative 4, pyrazolothiazole 5, pyrazolopyrimidine 6, and dihydropyrazolopyrimidine 7 when it interacted with hydrazine, carbon disulfide, formamide, and/or NH4SCN. Pyrazopyridine derivatives 8-12 were obtained by refluxing compound 3 with active methylene reagents. Additionally, compound 3 produced pyrazotriazolo pyrimidine 15 by reacting with triethylorthoformate and hydrazine hydrate, then refluxing the result in acetic anhydride. Synthesized derivatives 3-15 were evaluated pharmacologically for their anti-cancer, anti-microbial, and anti-Parkinsonian properties. Some of the produced compounds showed good pharmacological activity when compared to reference controls. A comprehensive synthesis, spectroscopic investigations, and pharmacological activity were all reported. KEY WORDS: Thienopyrimidine, Heterocyclic candidates, Anti-Parkinsonian, Anti-cancer, Antimicrobial Bull. Chem. Soc. Ethiop. 2026, 40(2), 429-442 DOI: https://dx.doi.org/10.4314/bcse.v40i2.12