Reaction Of Hydrazine Hydrate Research Articles

Hydrazine Sulfonic Acid, NH3 NH(SO3 ), the Bigger Sibling of Sulfamic Acid.

The reaction of hydrazine hydrate, N2 H4 ⋅ H2 O, and SO3 leads to hydrazine sulfonic acid (Pca21 , a=849.59(4) pm, b=482.18(2) pm, c=832.17(4) pm). Structure elucidation reveals the zwitter-anionic nature of the compound according to NH3 NH(SO3 ). With the barium salt Ba[NH2 NH(SO3 )]2 (H2 O), a first salt of hydrazine sulfonic acid has been prepared (P , a=489.75(5) pm, b=737.52(7) pm, c=1317.4(1) pm, α=88.238(4)°, β=84.761(4)°, γ=79.701(4)°). The compounds were characterized by vibrational spectroscopy, DFT calculations and thermal analyses.

Synthesis, Characterization and Evaluation of the Biological Activity of Some New Thiazolidine Derivatives Derived from Schiff bases

In this research, new compounds were synthesized via the reaction of dichloroacetic acid with two moles of piperidine. The novel acid 1 was converted to its ester 2. Acid hydrizide 3 was prepared by the reaction of hydrazine hydrate with new ester 2, which was later used to prepare derivatives of Schiff bases 4-13. In the last step, Schiff bases and thioglycolic acid were reacted to give thiazolidine derivatives 14-23. All these compounds were diagnosed using melting points, FTIR, 1HNMR and mass spectroscopy. Scheme 1 shows all the synthesized compounds' reaction steps and structures. Keywords: Thiazolidine; Schiff bases; biological activity; piperidine; dichloroacetic acid.

Unprecedented, catalyst‐free, and rapid one‐pot, three‐component green synthesis of substituted 3‐hydroxy‐2‐oxindoles in water

AbstractAn efficient, unprecedented, catalyst‐free, and rapid synthesis of substituted 3‐hydroxy‐2‐oxindoles is described by the one‐pot, three‐component reaction of hydrazine hydrate, ethyl acetoacetate, and isatins in water. The reported protocol is a green and general route for the simple preparation of new heteroaromatic substituted 3‐hydroxy‐2‐oxindoles in quantitative yields under very mild reaction conditions by using simple, cheap, and readily available materials. The developed method is effectively applicable to a variety of isatin substrates. Operational simplicity, mild and greener reaction conditions, short reaction time, a wide scope of substrates, good isolated yields of the products, and environmentally benign reaction medium are the distinctive features of the present method.

Synthesis, Computational Study of β-lactam Derivatives Bearing Quinazoline Schiff Bases as Anthelmintics

Background: Infections caused by parasites continue to pose a risk to both human and animal health. The most popular drug classes for treating these infections include thiabendazole, imidazothiazoles, levamisole, and avermectins (obtained from the fermentation products of Streptomyces avermitilis). The majority of bacteria that we come across in any form of infection are successfully combatted by β- lactam medicines. Similar to the majority of treatments, problems with treatment resistance to these drugs have evolved over time, necessitating the development of new anthelmintic medications. This study aims to investigate a series of quinazoline-bearing β-lactam rings as potent anthelmintic agents. Methods: The new series of quinazoline bearing β-lactam was synthesized via reaction of 5-bromo anthranilic acid with acetic anhydride to produce 6-bromo-2-methyl-4H-benzo (1,3) oxazin-4-one which was then converted into 3-amino-6-bromo-2-methylquinazolin-4(3H)-one by the reaction of hydrazine hydrate in the presence of anhydrous pyridine. The resultant intermediate then goes through a Schiff reaction with various aromatic aldehydes, followed by reflux with triethylamine and chloroacetyl chloride. Results: Structural assignments of these compounds have been made by elemental analysis, FTIR,1HNMR and Mass spectral data and the purity of the compounds was determined by TLC. Molecular docking studies showed the effective binding of synthesized derivatives with tubulin in comparison to the orientation of standard drugs. The anthelmintic activities of all the synthesized compounds were evaluated separately for their possible using common Indian earthworm Pheritima posthuma. Conclusion: A total of ten derivatives of quinazoline bearing β-lactam ring were designed, synthesized and evaluated against the Indian earthworm Pheritima posthuma. Out of ten derivatives, SQD2 and SQD6, showed promising anthelmintic activity when compared with standard drugs albendazole and piperazine citrate.

A hydrazine-bridged dinuclear ruthenium complex: Structural properties and biological activity

In this study, a new dimeric Ru(II) complex, [Ru(η6-p-cymene)Cl2]2(µ2-N2H4) (C1), readily synthesized with a reaction of hydrazine hydrate as ligand and [RuCl2(p-cymene)]2 dimmer in dichloromethane. The C1 complex was characterized structurally using IR, NMR, thermal gravimetry and single-crystal X-ray diffraction and theoretically using DFT techniques. Additionally, electrochemical, and optical properties were investigated in cyclic voltammetry and UV-visible spectroscopy. Furthermore, the C1 complex exhibited great antibacterial activity towards 16 Gram + and Gram – species and cell cytotoxicity towards human SH-SY5Y neuroblastoma cell, DU-145 prostate cancer cell, and A549 lung cancer cell lines.

An Agro‐Waste Based Eco‐Friendly Synthesis, Electrochemical Behavior and Anti‐oxidant Properties Evaluation of Pyrano[2,3‐c]pyrazole and Pyrazolyl‐4H‐chromenes Derivatives

AbstractAn efficient and economical one‐pot synthesis of pyrano[2,3‐c] pyrazoles and pyrazolyl‐4H‐chromenes using Water Extract of Mango Peel Ash (WEMPA) as a natural aqueous medium catalysts under microwave irradiation described. The microwave irradiation enhances the rate of the reaction, and decreases by‐product formation. The catalyst is obtained from the agro‐waste feedstock, by simple thermal treatment of dry peel of mango fruit followed by extraction of the resulted ash in water gave catalytic green solvent medium. In continuation of our research work on developing green chemistry protocol for bioactive molecule synthesis, herein, first time described pyrano[2,3‐c]pyrazole and pyrazolyl‐4H‐chromene derivative synthesis by the reaction of hydrazine hydrate (1), malononitrile (2), ethyl acetoacetate (3), aryl aldehydes (4), and/or salicylaldehyde (5). Some of the selected pyrano[2,3‐c]pyrazole (6) and pyrazolyl‐4H‐chromene (7) derivatives are tested for their in vitro antioxidant activity (free radical scavenging) by DPPH assay method. The assay result revealed, compounds 6 a, 6 h, 6 i and 7 d showed significant antioxidant activities comparison with refrence ascorbic acid. Some of the selected derivatives are characterized by FT‐IR, 1H‐, 13C‐NMR and mass spectrometry analysis, and also tested for their electrochemical behavior studies using a cyclic voltammetry.

Catalyst-free synthesis of tetrahydrodipyrazolopyridines via an one-pot tandem and green pseudo-six-component reaction in water

BackgroundA new, green and environmentally friendly protocol has been developed for the synthesis of tetrahydrodipyrazolopyridine derivatives. The structures of these products were determined in terms of melting point, FTIR, NMR and Mass spectroscopy.ResultsThe tetrahydrodipyrazolopyridine derivatives were synthesized in water through a catalyst-free pseudo-six-component reaction of hydrazine hydrate, ethyl acetoacetate, ammonium acetate and aldehyde at room temperature.ConclusionsThis novel procedure has some advantages such as aqueous media, high yield and simple work-up.Graphical

Synthesis, molecular docking, molecular dynamics and evaluation of Drug-Likeness properties of the fused N-Formyl pyrazoline substituted new dehydroepiandrosterone derivatives

The hybrid molecules bearing heterocyclic structures in the A or D rings of steroids have significant biological activity. 16 (E)-Hetereoarylidene steroids were synthesized from the reaction of different heteroaromatic carbaldehydes and trans-Dehydroepiandrosterone (DHEA) in a basic medium. Then, synthesis of the N-formyl pyrazoline substituted new DHEA derivatives were carried out from the reaction of hydrazine hydrate and 16 (E)-hetereoarylidene steroids. The structures of the synthesized compounds were elucidated by elemental analysis, FT-IR, 1H NMR, and 13C NMR spectroscopy. To investigate the activation pathway of synthesized N-formyl pyrazoline substituted steroid derivatives, a molecular docking study was performed on human cytochrome P450-(CYP17A1: PDB ID 5IRQ) with the help of the free AutoDock Vina. 100 ns molecular dynamic simulation process was performed to monitor the behavior of the complex structure formed by CYP17A1 and to calculate the stability over time of 2a and 2d (-9.8 kcal/mol), which gave the lowest value according to the results obtained in the molecular docking study with AutoDock Vina. Accordingly, RMSD, RMSF, Rg, and SASA analyzes of 2a and 2d were performed, and MMPBSA was calculated. Lastly, the ADMET (absorption, distribution, metabolism, excretion, and toxicity) analyses of the novel steroid derivatives were investigated. Communicated by Ramaswamy H. Sarma

Synthesis of novel 2,5-bis(substituted thio)-1,3,4-thiadiazoles by acid catalyzed intermolecular cyclization reactions of substituted dithiocarbazates as a possible 2019-nCoV main protease inhibitor

A convenient and facile synthesis of a privileged pharmaceutical scaffolds, 2,5-bis(substituted thio)-1,3,4-thiadiazoles is accomplished. The reaction of hydrazine hydrate with carbon disulfide and substituted alkyl/aryl chloride in basic medium yielded S-substituted alkyl/aryl dithiocarbazates in high yield. These dithiocarbazates on reaction with tetrafluoro acetic acid underwent a unique acid catalyzed intermolecular cyclization reaction to afford a novel 2,5-bis(substituted thio)-1,3,4-thiadiazoles. A simple procedure and high yields are the characteristic features of these reactions. These compounds are characterized on the basis of physico-chemical and spectral (FT-IR, ESI Mass, 1H, 13C and DEPT 135° 13C {1H} NMR) studies. Compound 2b crystallizes in orthorhombic system with point group P bca. Using the DFT/B3LYP/6–311 G (d,p) level of theory, HOMO-LUMO energy gap and molecular electrostatic potential (MEP) analyses were carried out. The HOMO-LUMO energy gap allowed the calculation of chemical hardness, chemical inertness, electronegativity and the electrophilicity index of the molecule, which depicted their potential kinetic stability and reactivity. The molecular docking studies of 2b-2e with 2019-nCoV main protease(7BRO) revealed binding free energies of (ΔGb) = -6.22, -5.38, -4.43 and -4.25 kcal mol−1 respectively. Docking study revealed that the aromatic congeners exhibit appreciable therapeutic efficiency to be used as 2019-nCoV main protease inhibitors.

SLS-catalyzed Multi-component One-pot Reactions for the Convenient Synthesis of Spiro[indoline-3,4’-pyrano [2,3-c]pyrazole] Derivatives

Background and Objective: Spiro[indoline-3,4′-pyrano[2,3-c]pyrazole] derivatives are an important heterocyclic compounds. These compounds shows wide range of biological properties and exhibits varied pharmaceutical applications. Pyranopyrazoles, which are basically fused heterocyclic compounds and act as vasodilators, hypertensive, hypoglycaemic and anticancer agents. Methods: An efficient and micelle-promoted surfactant catalyzed synthesis of spiro[indoline- 3,4′-pyrano[2,3-c]pyrazole] derivatives have been achieved via one-pot four-component reaction of hydrazine hydrate (phenyl hydrazine), ethyl acetoacetate, malononitrile (ethyl cyanoacetate) and isatin under thermal conditions (at 60°C) in water as a solvent. Results: Sodium lauryl sulphate (SLS) used has been found to be an efficient and green catalyst. The compounds reported during this work were obtained in excellent yield, in a short duration of time and ease of work up. They were purified by recrystalization from ethanol, and also the synthesized compounds were characterized by various spectroscopic techniques. Conclusion: The method offers several advantages such as safe, cost-effective and catalyst easily recovered and reused for a minimum of five cycles, that confirms its good stability. Short reaction times, high yield and usage of eco-friendly catalyst and solvent are the key features of this methodology.

Synthesis of N,N'-Diacylhydrazines and their Use in Various Synthetic Transformations

Background: N,N'-Diacylhydrazines are involved in many synthetic transformations. The current work reviews the synthesis of N,N'-diacylhydrazines and their use in various synthetic transformations. Results: Three synthetic routes are commonly used to produce N,N'-diacylhydrazines. They are produced through the coupling of acyl chlorides and carbohydrazides, the reaction of hydrazine hydrate and carboxylic acids or isocyanates, and the dimerization of carbohydrazides. They can be oxidized to produce the corresponding esters and act as precursors in the synthesis of various heterocycles such as 1,3,4-oxadiazoles, 1,3,4-thiadiazoles, 1,2,4-triazoles, pyrazoles, tetrazines, and crown ethers. Conclusions: Various synthetic procedures have been reported for the production of N,N'- diacylhydrazines. N,N'-Diacylhydrazines are involved in the synthesis of various heterocycles.

The inhibition of mild steel corrosion in 0.5 M H2SO4 solution by N-phenethylhydrazinecarbothioamide (N-PHC)

A new corrosion inhibitor namely N-phenethylhydrazinecarbothioamide (N-PHC) was synthesized through the reaction of hydrazine hydrate and (2-isothiocyanatoethyl)benzene. N-PHC has been characterized by spectroscopically techniques and CHN micro-elemental analysis. The inhibitive activity of N-PHC on mild steel corrosion in 0.5 M sulphuric acid solution was examined by the weight loss techniques. The findings exhibited that the inhibition efficiency increased with an increase in the concentration of N-PHC and decreased with an increase in temperature. The inhibition efficiency reached 94.7% with 250 ppm at 303 K. The inhibitive mechanism involved chemical adsorption and the adsorption of the N-PHC molecules through active sites on the surface of mild steel to control or retard corrosion. The adsorption isotherm obeyed the Langmuir isotherm.

WITHDRAWN: A green approach synthesis of substituted 3-phenyl-5-napthyl pyrazole and its microbial applications

Abstract A sequence of 3-phenyl-5-napthyl substituted pyrazole derivatives (7a–7c) was synthesized in good yields by a condensation reaction of 1-naphthaldehyde substituted acetophenone followed by a reaction of hydrazine hydrate. Analytical and spectral techniques for the representative compounds 7a–7c have confirmed the structure of the reaction products. All synthesized compounds have been tested for antibacterial, antifungal, and antioxidant activity. Compound 7b has shown significant antibacterial and antifungal activity concerning the standard drug fluconazole.

Multiwalled carbon nanotubes/guanidine/Ni (II): A new and effective organometallic catalyst for the green synthesis of pyrazolopyranopyrimidines

In this research, we report the first example of the use of multiwalled carbon nanotubes/guanidine/Ni (II) as a new and effective catalyst. The supported catalyst was prepared through a new method and characterized by Fourier transform infrared, scanning electron microscopy, energy‐dispersive spectroscopy, inductively coupled plasma, thermogravimetric analysis, ultraviolet diffuse reflectance spectroscopy, and transmission electron microscopy. Obtained catalyst was used for green and efficient synthesis of pyrazolopyranopyrimidines via four‐component reaction of hydrazine hydrate, ethyl acetoacetate, barbituric acid, and aromatic aldehydes under ultrasonic condition. All products were obtained in high yields and short reaction times. Also, the prepared catalyst was easily separated from the reaction mixture and reused for several times without significant loss of activity.

Liquid crystal and photoluminescent properties of a series of symmetrical 1,2-bis(4-alkoxybenzylidene)hydrazines bearing long-tails of hydrocarbon chain

ABSTRACT In this work, 1,2-bis[4-(n-alkoxy)benzylidene]hydrazine (n-alkoxy: O(CH2)nH, n = 11–18 or 20), a symmetrical series of azines (linear compounds with rod-like shape structure), were synthesised using a very simple two-step procedure as a part of our continuing effort in evaluating hydrophobic 1,2-disubstituted hydrazine compounds as photoluminescent liquid crystalline materials. The first step of the synthesis involved the alkylation of the OH group of 4-hydroxybenzaldehyde in basic medium using the Williamson method to obtain 4-alkoxybenzaldehydes. While the second step included the condensation reaction of hydrazine hydrate and appropriately 4-alkoxybenzaldehydes compounds (mole ratio 1:2, respectively) in acidic medium under ambient conditions. The prepared compounds were characterised and their structures elucidated depending upon infrared (IR), ultraviolet-visible (UV–Vis), nuclear magnetic resonance (1HNMR, 13CNMR, DEPT NMR, 2D 1H-1H-COSY and 2D 1H-13C- HSQC) and elemental analysis (CHN). Liquid crystalline behaviour and photoluminescent properties were studied using polarised light optical microscopy (POM), fluorescence emissions (FE), differential scanning calorimetry (DSC) and X-ray powder diffraction (XRD) techniques. The studies showed that all of these compounds are enantiotropic liquid crystalline materials exhibiting smectic (SmA and SmC) and nematic (droplet and thread) mesophases . The study also displayed that all of the prepared compounds are photoluminescent in the crystalline and liquid crystal states.

Synthesis and Crystal Structure of (S)-2-(3-Oxo-1,3- Dihydroisobenzofuran-1-yl)phthalazin-1(2H)-One

A heterocycle compound, C16H10N2O3, has been synthesized by the reaction of hydrazine hydrate, 2-carboxybenzaldehyde and magnesium chloride hexahydrate in CH3CH2OH-water (v: v= 1: 1) solution. The crystal structure of (S)-2-(3-oxo-1, 3- dihydroisobenzofuran-1-yl) phthalazin-1(2H)-one has been determined by X-ray single crystal diffraction analysis. The result shows that the (S)-2-(3-oxo-1, 3- dihydroisobenzofuran-1-yl) phthalazin-1(2H)-one belongs to triclinic, space group P-1 with a = 7.2049(8) Å, b = 8.0215(9) Å, c = 10.9938(14) Å, a = 81.120(10)°, β = 85.939(10)°, γ =88.934(9)°, V = 626.17(13) Å3, Z = 2, Dc = 1.476 mg·m−3, μ = 0.104 mm−1, F(000)=288, and final R 1 =0.0935, ωR 2 = 0.1018. The title compound molecules form 3D network structure by the interaction of aza-heterocycle and oxa-heterocycle of (S)-2-(3-oxo-1, 3-dihydroisobenzofuran-1-yl) phthalazin-1(2H)-one molecules.

Novel Bis(2‐cyanoketene‐S,S‐/S,N‐acetals): Versatile Precursors for Novel Bis(aminopyrazole) Derivatives

A synthesis of novel bis(aminopyrazoles) by the reaction of hydrazine hydrate with the appropriate bis(2‐cyanoketene‐S,N‐acetals) was reported. The latter compounds were prepared by treatment of bis(cyanoacetamides) with phenyl isothiocyanate in KOH/EtOH and subsequent alkylation with methyl iodide. The utility of bis(2‐cyanoketene‐S,S‐acetals) as building blocks for novel bis(aminopyrazoles) was also investigated.

Unanticipated Heterocyclization from Reaction of Hydrazine Hydrate and/or Hydrazine Dihydrochloride with 1‐Ethyl‐4‐hydroxyquinolin‐2(1H)‐one

Unanticipated Heterocyclization from Reaction of Hydrazine Hydrate and/or Hydrazine Dihydrochloride with 1‐Ethyl‐4‐hydroxyquinolin‐2(1H)‐one

Synthesis and structure of some new Schiff bases, derivatives of 2-((4-((R-benzylidene)amino)-5-(2-fluorophenyl)-4H-1,2,4-triazole-3-yl)thio)acetohydrazides

Triazole derivatives are among wide range of pharmacological agents, such as antimicrobial, analgesic, anti-inflammatory, anticonvulsant, antitumor, antimalarial, antiviral, antiproliferative, anti-cancer drugs etc. The importance of triazole derivatives is in their various biological properties. That is why they have a good position in heterocyclic chemistry. The purpose of this work was to synthesize and define physical and chemical parameters of new 2-((4-((R-benzylidene)amino)-5-(2-fluorophenyl)-4H-1,2,4-triazole-3-yl)thio)acetohydrazide derivatives. Material and methods. Studying of physical and chemical properties of synthesized compounds was carried out in accordance with the methods of the State Pharmacopoeia of Ukraine. The melting temperature of the synthesized compounds was set on the automatic device for determining the melting temperature MPA100. The Elementar Vario L cube element element analyzer was used to determine the elemental composition of the synthesized substances. 1 H NMR spectra of compounds were recorded using a Varian Mercury VX-200 spectrometer ( 1 H, 200 MHz), solvent ­ DMSO- d6 , internal standard ­ tetramethylsilane (TMS). Results. 2-((4-((R-benzylidene)amino)-5-(2-fluorophenyl)-4H-1,2,4-triazole-3-yl)thio)acetohydrazides (1a-c) were used as initial materials. These compounds were obtained by reaction of hydrazine hydrate 1.5 molar excess with the corresponding 2-((4-((4-R-benzylidene)amino)-5-(2-fluorophenyl)-4H-1,2,4-triazole-3-yl)thio)acetic acid. Subsequently, corresponding R'-benzaldehyde was added to the synthesized products 1 a-c in the mixture of acetic acid-isopropyl alcohol (2: 1) and heated for 30 minutes, after which the final product was isolated after 6-8 hours. Conclusions. As a result of the research 18 new 2-((4-((R-benzylidene)amino)-5-(2-fluorophenyl)-4H-1,2,4-triazole-3-yl)thio)acetohydrazides (1a-c) and their R'-N-benzylidene-2-((4-((4-R-benzylidene)amino)-5-(2-fluorophenyl)-4H-1,2,4-triazole-3-yl)thio)acetohydrazides (2a-e, 3a-h, 4a, 4b) were synthesized. The structure of the obtained substances was confirmed by the data of elemental analysis, 1 H NMR spectroscopy.

From mesogens to metallomesogens. Synthesis, characterisation, liquid crystal and luminescent properties

ABSTRACTContinuation with our previous investigation which refers to the synthesis of a series of hydrophobic symmetrical azine compounds: 1,2-bis[4-(n-alkoxy)benzylidene]hydrazine (where, n-alkoxy: O(CH2)nH, n = 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 12, 16 or 18), a series of hydrophobic asymmetrical azine compounds: [1-(4-propyloxy)-2-(4ʹ-(n-alkoxy))benzylidene]hydrazine (where, n-alkoxy: O(CH2)nH, n = 1, 2, 4, 5, 6, 7, 8, 9, 10, 12, 16 or 18) was synthesised following an efficient and practical method. These compounds were synthesised by the condensation reaction of hydrazine hydrate with 4-propyloxybenzaldehyde and appropriately 4-(n-alkoxy)benzaldehydes in acidic medium and ambient conditions (very simple way with no need of any sophisticated techniques). Moreover, two new series of silver(I) complexes based on symmetrical or asymmetrical azines have been synthesised (linear-binuclear type complexes with the general formula [Ag2(L)(NO3)2] were obtained). The organic compounds and their silver(I) complexes were characterised using different techniques: microelemental analysis and spectral data (FTIR, UV–Vis, 1HNMR, 13C{1H}NMR, 2D 1H-1H-COSY, 2D 1H-13C-HSQC and mass spectra) as well as molar conductivity measurements for silver(I) complexes. Liquid crystal behaviour of the prepared compounds were studied using polarised light optical microscopy and confirmed with differential scanning calorimetry and X-ray powder diffraction techniques. The studies revealed that all azine compounds and some of silver(I) complexes are liquid crystal materials. The luminescent properties of all the prepared compounds were also investigated which confirmed that all of these compounds are photo-luminescent in the crystalline solid state and in the mesophase.