Hydrazine Carboxylate Research Articles

Effect of pendent alkyl group of ancillary ligand on molecular structures of new metal(II)-2, 4-dinitro benzoate complexes- spectral, structural and photoluminescence studies

A series of new metal(II) complexes having general formulae, [M (2, 4-dnb)2(L)2] (where 2, 4-dnbH = 2,4-dinitro benzoic acid; M = Co(1), Ni(2), Zn(3) and Cd(4), L = methyl hydrazine carboxylate (mc); M = Co(5), Ni(6), Zn(7) and Cd(8), L = ethyl hydrazine carboxylate (ec)) were prepared and characterized using elemental analysis, UV-Visible, FT-IR, emission spectroscopic and powder XRD techniques. Single crystal X-ray study for 3 and 7 shows that metal ion, in both complexes, adopts distorted MN2O4 geometry arising from a pair of N,O-chelating methyl/ethyl hydrazine carboxylate ligands at equatorial sites and monodendate 2, 4-dnb ions at the axial sites. The pair of nitrogen (or) oxygen atoms of chelating ligands (L) are trans positioned in 3 whereas they are cis positioned in 7. All the complexes exhibit photoluminescence property. On heating all the complexes show explosive nature of decomposition.

A 1D silver(I) coordination polymer of a new hydrozone-hydrazide ligand: Spectral, structural, emission, and anti-bacterial properties and its application as a solid source precursor for silver oxide nanoparticles

A new one-dimensional (1D) coordination polymer of composition [Ag(L)(NO3)]n was synthesized by a reaction of silver(I) nitrate with a new hydrazone-hydrazide ligand (L) derived from 2-acetyl furan and ethyl hydrazine carboxylate. Both the ligand, L, and the silver(I) complex were characterized using elemental analysis, electron impact mass spectrometry (EI-Mass), infrared (IR), proton nuclear magnetic resonance (1H NMR), ultraviolet–visible (UV–Vis) spectroscopy, and emission spectroscopy analyses. Single-crystal X-ray diffraction study shows that the structure of the silver(I) complex consists of 1D polymeric chains in which silver(I) ion is in four coordination complexes arising from one N, O-chelating L and two O, O′-bridging nitrate anions. The complex emitted energy around 360 nm and was used as a single precursor for synthesis of silver oxide nanoparticles (Ag2O NPs). From transmission electron microscopy (TEM) and higher-resolution TEM (HR-TEM) images, the as-prepared Ag2O NPs were nearly spherical in shape with average particle sizes of approximately 22–24 nm. Anti-bacterial properties of both the ligand and the metal complex were studied.

Synthesis, characterization, and theoretical studies of (E)-t-butyl-2-((E)-2-methyl-3-phenylallylidene) hydrazine carboxylate and (E)-t-butyl-2-((E)-3-phenylallylidene) hydrazine carboxylates as a possible Mcl-1 antagonists

Refluxing t-butyl carbazate with the corresponding aldehyde in ethanol yielded (E)-tert-butyl 2-((E)-2-methyl-3-phenylallylidene)hydrazinecarboxylate (1) and (E)-t-butyl-2-((E)-3-phenylall ylidene)hydrazine carboxylate (2) in appreciable amounts. The products were identified using spectral data analysis. To confirm the trans-nature of the double bond in the synthesized compound 1, single crystal X-ray analysis was carried out. The trans-nature of double bond in compound 2, which could not be crystallized, was however deduced from the vicinal coupling constant of the two protons involved in the double bond. Single crystal X-ray study unfurled that compound 1 crystallizes in a monoclinic system with P21/c space group. Theoretical calculations of both the compounds was carried out at DFT/B3LYP/6-311G (d, p) level of theory. Theoretically obtained parameters demonstrated good compliance with the experimentally obtained data for compound 1. Molecular Electrostatic Potential Surface (MEPS) and Frontier Molecular Orbital (FMO) analysis were performed for both the compounds. Calculation of HOMO-LUMO energy gap and various other related parameters depicted a similar reactivity behaviour of both the compounds. To unravel the biological target of the compounds, Online Pass Prediction divulged that compounds, 1 and 2 are moderately potent against Mcl-1 enzyme, with Pa value of 0.82 and 0.61 respectively. Molecular docking of 1 and 2 against Mcl-1 protein conferred binding free energy of −6.26 and −3.11 kcal/mol respectively indicating moderate binding efficiency of the compounds.

Synthesis of t-butyl 2-(4-hydroxy-3-methoxybenzylidene)hydrazine carboxylate: Experimental and theoretical investigations of its properties

A convenient and facile synthesis of t-butyl-2-(4-hydroxy-3-methoxybenzylidene)hydrazine carboxylate (1) was accomplished by refluxing t-butyl carbazate with an appropriate aldehyde in ethanol. The resulting compound was characterized using spectral data analysis augmented by X-ray. Single crystal analysis depicted that compound 1 crystallizes in a monoclinic crystal system with P 21/c space group having trans-geometry at the CN bond. The structural and electronic properties of the title compound have been calculated using DFT/B3LYP/6-311G (d,p) level of theory. Theoretically obtained parameters were well compared to the experimentally obtained results which depicted excellent agreement. Molecular electrostatic potential surface, frontier orbital analysis and vibrational analysis were also carried out. HOMO-LUMO energy gap was calculated which allowed the calculation of relative reactivity descriptors like chemical hardness, chemical inertness, chemical potential, nucleophilicity and electrophilicity index of the synthesized product. Pass prediction was carried out which revealed that compound 1 can be highly active against Mcl-1 enzyme, with Pa of 0.544. Based on Pass, molecular docking of compound 1 was carried out against Mcl-1 protein. Compound 1 displayed a binding free energy of −5.22 kcal/mol and inhibition constant of 149.06 μM and 1 depicted only alkyl hydrophobic and mixed pi/alkyl hydrophobic interactions with Mcl-1 enzyme. In short, this study reveals the synthesis of a new schiff base, and unravels the structural, electronic and biological properties of the title compound, paving way for further research in the field of drug development.

Synthesis, Spectral, X‐Ray Diffraction, DFT, and Nematicidal Activity of Mixed Ligand Complexes of Ethyl 2‐(2‐Hydroxybenzylidine)‐Hydrazine Carboxylate and 1,10‐Phenanthroline with Some Transition Metals

In this work, mixed ligand complexes derived from ethyl 2‐(2‐hydroxybenzylidine)‐hydrazine carboxylate (HL) and 1,10‐phenanthroline (Phen) as ligands were synthesized and their structures elucidated by elemental analysis, infrared (IR), electronic,1H NMR, and mass spectra, X‐ray diffraction (XRD), magnetic susceptibility measurements, and TG/DTG analyses. The analytical and spectral data support the formation of the complexes with the central ion in each complex six‐coordinated and a slightly distorted octahedral geometry. The IR spectra showed that HL and Phen ligands act as neutral bidentates. The XRD patterns of the complexes showed their crystalline nature. The calculated bond length and the force constant F(U═O) in the uranyl complex are 1.738 Å and 685.90 Nm−1, respectively. The molar conductance values of the synthetic complexes in DMF were found to be in the range 5.00–274.06 S cm2/mol at room temperature. The thermodynamic parameters were evaluated by using the Coats–Redfern (CR) and Horowitz–Metzeger (HM) methods. Theoretical molecular structures were investigated by the density functional theory/B3LYP method using the Gaussian 98 W basis set. The nematicidal activity of the ligands and its metal complexes was also studied.

Inhibitory effect of coumarin derivatives on apple (cv. Idared) polyphenol oxidase

Inhibitory effect of 32 coumarin derivatives (20 Schiff bases, 5 thiosemicarbazides, 5 thiazolidinones, and their precursors, 7- hydroxy-4-methylcoumarin and 4-methylcoumarin- 7-yl hydrazine carboxylate) on partially purified apple polyphenol oxidase was investigated. Thirteen coumarin derivatives inhibited polyphenol oxidase (5 Schiff bases, 5 thiosemicarbazides, 1 thiazolidinone, 4-methyl- 7-hydroxycoumarin and 4-methylcoumarin-7-yl hydrazine carboxylate), while 19 derivatives showed no effect on enzyme activity. The most effective inhibitors were thiosemicarbazides, with 4-methyl-1-(2-(4-methyl-2-oxo-2H-chromen- 7-yloxy)acetyl) thiosemicarbazide (compound C23) being the most prominent inhibitor (IC50 = 10.45 µM). The importance of thiosemicarbazide moiety as crucial structure element for strong apple PPO inhibition was confirmed by its cyclisation to thiazolidinone bearing the same substituents as corresponding thiosemicarbazide. Capture of the sulphur atom of thiosemicarbazide group within tiazolidinone ring caused significant loss of inhibitory effect against apple PPO.

Determination of genotoxic impurity in atazanavir sulphate drug substance by LC–MS

A sensitive LC–MS method was developed for the determination of tert-butyl 2-[4-(pyridine-2-yl) benzyl] hydrazine carboxylate (GTI-A), a genotoxic impurity in Atazanavir sulphate drug substance. The method was validated as per International Council for Harmonization guidelines, for QL, DL, linearity and accuracy. The QL and DL values obtained were 1.1ppm and 0.3ppm respectively. The Correlation coefficient found for the linearity study was 0.999. The % recovery of the added impurity in the range of 96.4–100.4 ensured the accuracy of the method.

Investigation of Electroactive and Antibacterial Properties of Polyethersulfone Membranes Blended With Copper Nanoparticles

In this study, copper nanoparticles (CuNPs) were synthesized by sonochemical reduction of copper(II) hydrazine carboxylate complex in an aqueous medium. Asymmetric neat polyethersulfone (PES) and PES/CuNPs nanocomposite membranes were prepared via phase inversion method by dispersing copper nanoparticles in the PES casting solutions. X‐ray diffraction and particle size distribution analyses were applied to characterize the CuNPs. Moreover, field emission scanning electron microscopy, atomic force microscopy (AFM), conductive atomic force microscopy (C‐AFM), contact angle goniometry, and four‐point probe techniques were used to investigate the physical and morphological properties of the PES/CuNPs nanocomposite membranes. Synthesized CuNPs were added into the casting solution at different concentrations. The effect of CuNPs concentration (0, 0.25, 0.5, 1.0, 2.0%, w/w) was tested on morphological changes and antibacterial properties of the prepared membranes. These copper nanoparticle composite membranes hold great promise in the engineering field for the production of sensors and self‐cleaning membranes.

A hydrazone Schiff base single crystal (E)-Methyl N′-(3,4,5-trimethoxybenzylidene) hydrazine carboxylate: Physicochemical, in vitro investigation of antimicrobial activities and molecular docking with DNA gyrase protein

Hydrazone Schiff bases have been widely explored for their antimicrobial, anticancer, anticonvulsant properties. The aim of the present work is to investigate the spectroscopic, electrochemical, thermal properties, in vitro study of antimicrobial activity and molecular docking studies of the MBHC compound. Slow evaporation solution growth technique was used to grow the single crystal of the MBHC compound. Single crystal X-ray diffraction, FTIR and FT-Raman spectroscopic studies are performed and confirmed the grown MBHC compound. UV–Vis spectroscopy and electrochemical studies deduced the absorption region and HOMO-LUMO band gap value of the compound. Resazurin reduction assay method was utilized to perform antibacterial and antifungal studies which resulted in lesser effectiveness of the MBHC compound compared to the erythromycin and fluconazole tablets. Molecular docking of the MBHC compound with the DNA gyrase protein exhibited the good binding affinity with energy of −43.196kcal/mol and docking score of −6.266 and having good interaction with aminoacids – ASP81 and ARG84.

Synthesis and biological evaluation of hydrazone derivatives as antifungal agents.

Emerging yeasts are among the most prevalent causes of systemic infections with high mortality rates and there is an urgent need to develop specific, effective and non-toxic antifungal agents to respond to this issue. In this study 35 aldehydes, hydrazones and hydrazines were obtained and their antifungal activity was evaluated against Candida species (C. parapsilosis, C. tropicalis, C. krusei, C. albicans, C. glabrata and C. lusitaneae) and Trichosporon asahii, in an in vitro screening. The minimum inhibitory concentrations (MICs) of the active compounds in the screening was determined against 10 clinical isolates of C. parapsilosis and 10 of T. asahii. The compounds 4-pyridin-2-ylbenzaldehyde] (13a) and tert-butyl-(2Z)-2-(3,4,5-trihydroxybenzylidine)hydrazine carboxylate (7b) showed the most promising MIC values in the range of 16–32 μg/mL and 8–16 μg/mL, respectively. The compounds’ action on the stability of the cell membrane and cell wall was evaluated, which suggested the action of the compounds on the fungal cell membrane. Cell viability of leukocytes and an alkaline comet assay were performed to evaluate the cytotoxicity. Compound 13a was not cytotoxic at the active concentrations. These results support the discovery of promising candidates for the development of new antifungal agents.

Investigation of characterization and biofouling properties of PES membrane containing selenium and copper nanoparticles

Selenium and copper nanoparticles exhibit superior antioxidant activity, unique properties, and great potential applications that make them very attractive for developing new composite materials. In this study, polyethersulfone (PES) ultrafiltration membrane was modified by dispersing nano-sized selenium (nSe) and copper (nCu) particles uniformly in a PES solution (18% polymer weight) and casted by a phase inversion process. Membranes with four different weight ratios of nSe and nCu to PES of 0.002, 0.010, 0.030, and 0.050 were tested. Selenium nanoparticles were prepared by the reduction of aqueous sodium selenite solution with freshly prepared glucose solution. The method was capable of producing spherical selenium nanoparticles in a size range of about 150–175nm, under ambient conditions. The synthesized nanoparticles can be separated easily from the aqueous solutions by a high-speed centrifuge and can be re-dispersed in an aqueous medium by an ultra-sonicator. The effects of temperature, time, and stirring rate on the size of the selenium nanoparticles were studied. In addition, nanoscale particles of metallic copper clusters were prepared by sonochemical reduction of copper(II) hydrazine carboxylate Cu–(N2H3COO)2·2H2O complex in an aqueous medium. Reduction process takes place under an argon atmosphere over a period of 2–3h and the size of copper nanoparticles was about 90–105nm. The synthesized selenium and copper nanoparticles were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), and particle size distribution techniques. Moreover, Se/PES and Cu/PES blend membranes were also characterized using contact angle goniometer, scanning electron microscopy (SEM), and permeation tests. Anti-fouling performance was examined using activated sludge as a biological suspension. The protein rejection study was also carried out using the bovine serum albumin (BSA) solution. The morphology and permeation properties of the blend membranes were found to be dependent on the amounts of nanoparticles. Compared to neat PES membrane, the 0.05 Cu/PES membrane exhibited highest protein rejection ratio (86.3%). However, the Se/PES membranes showed better antifouling performance (lower flux decline). The blending membranes with nanoparticles are considered to be suitable for the prevention of biofouling.

Divalent transition metal complexes of 3,5-pyrazoledicarboxylate

New divalent transition metal 3,5-pyrazoledicarboxylate hydrates of empirical formula Mpz(COO)2(H2O)2, where M=Mn, Co, Ni, Cu, Zn and Cd (pz(COO)2=3,5-pyrazoledicarboxylate), metal hydrazine complexes of the type Mpz(COO)2N2H4 where M=Co, Zn or Cd and Mpz(COO)2nN2H4·H2O, where n=1 for M=Ni and n=0.5 for M=Cu have been prepared and characterized by physico-chemical methods. Electronic spectroscopic data suggest that Co and Ni complexes adopt an octahedral geometry. The IR spectra confirm the presence of unidentate carboxylate anion (Δν=νasy(COO–)–νsym(COO–)>215 cm–1) in all the complexes and bidentate bridging hydrazine (νN–N=985–950 cm–1) in the metal hydrazine complexes. Both metal carboxylate and metal hydrazine carboxylate complexes undergo endothermic dehydration and/or dehydrazination followed by exothermic decomposition of organic moiety to give the respective metal oxides as the end products except manganese pyrazoledicarboxylate hydrate, which leaves manganese carbonate. X-ray powder diffraction patterns reveal that the metal carboxylate hydrates are isomorphous as are those of metal hydrazine complexes of cobalt, zinc and cadmium.

New Multi-1,2,3-Selenadiazole Aromatic Derivatives

The aromatic polyketones 3a-d are versatile compounds for the synthesis of the multi-1,2,3-selenadiazole aromatic derivatives 1a-d. The preparation starts with the reaction between the multi-bromomethylene benzene derivatives 2a-d and 4-hydroxy-acetophenone to give compounds 3a-d which are transformed through the reaction with semicarbazide hydrochloride or ethyl hydrazine carboxylate into the corresponding semicarbazones derivatives 4a-d or hydrazones 5a-d. The reaction with selenium dioxide leads to regiospecific ring closure of semicarbazones or hydrazones to give the multi-1,2,3-selenadiazole aromatic derivatives in high yield.

ChemInform Abstract: Hydrazine Carboxylate t‐Butyl Ester (Boc‐Hydrazide): Its Properties and Applications

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

Development and Scale Up of a Route to Cyclohexylhydrazine Dimethanesulfonate

A mild, high-yielding synthesis of cyclohexylhydrazine dimethanesulfonate has been developed that is suitable for further scale up. The process consists of three chemical steps: condensation of cyclohexanone with tert-butyl carbazate, reduction of the hydrazone carboxylate to a hydrazine carboxylate with borane−THF, and hydrolysis, decarboxylation, and derivatization with methanesulfonic acid. From studies using a reaction calorimeter, it was determined that the last stage of the process occurs in two discrete steps, requiring 2 equiv of methanesulfonic acid. The first equivalent of acid is consumed by N-protonation. Deprotection of the Boc group occurs with the second equivalent of acid, as evident by the gas evolution. The heat of reaction for the acid addition was determined to be 57.7 kJ/kg and represents an adiabatic temperature rise of 27.4 °C.

Synthesis, Characterization, and Properties of Metallic Copper Nanoparticles

Nanoscale particles of metallic copper clusters have been prepared by two methods, namely the thermal reduction and sonochemical reduction of copper(II) hydrazine carboxylate Cu(N2H3COO)2·2H2O complex in an aqueous medium. Both reduction processes take place under an argon atmosphere over a period of 2−3 h. The FT-IR, powder X-ray diffraction, and UV−visible studies support the reduction products of Cu2+ ions as metallic copper nanocrystallites. The powder X-ray analysis of the thermally derived products show the formation of pure metallic copper, while the sonochemical method yields a mixture of metallic copper and copper oxide (Cu2O). The formation of Cu2O along with the copper nanoparticles in the sonochemical process can be attributed to the partial oxidation of copper by in situ generated H2O2 under the sonochemical conditions. However, the presence of a mixture of an argon/hydrogen (95:5) atmosphere yields pure copper metallic nanoparticles, which could be due to the scavenging action of the hydroge...

An electron spin resonance study of Mn2+ doped calcium hydrazine carboxylate monohydrate

Single crystals of calcium hydrazine carboxylate, monohydrate have been studied by ESR of Mn2+ doped in the calcium sites. X-band ESR indicated a large crystal field splitting necessitating experiments at Q band. The analysis shows two magnetically inequivalent (but chemically equivalent) sites withg xx = 2.0042±0.0038,g yy=2.0076 ±0.0029,g zz=2.0314±0.001,A zz=0.0099±0.0002 cm−1,A xx=0.0092±0.0002 cm−1,A yy=0.0082±0.0002 cm−1,D=3/2D zz=0.0558±0.0006 cm−1, andE=1/2 (D yy−D yy)=0.0127±0.0002 cm−1.One of the principal components of the crystal field, (D zz), is found to be along the Ca ↔ Ca direction in the structure and a second one, (D xx), along the perpendicular to the plane of the triangle formed by three neighbouring calciums. TheA tensor is found to have an orientation different from that of theg andD tensors reflecting the low symmetry of the Ca2+ sites.

Hydrazine carboxylate precursors to fine particle titania, zirconia and zirconium titanate

Titanyl hydrazine carboxylate dihydrate, TiO(N 2H 3COO) 2.2H 2O, zirconyl hydrazine carboxylate dihydrate, ZrO(N 2H 3COO) 2.2H 2O and their solid solution, ZrTiO 2(N 2H 3COO) 4.4H 2O have been prepared for the first time and investigated as precursors to fine particle TiO 2, ZrO 2 and ZrTiO 4 respectively. Titania(anatase) formed has a very high surface area of 110 m 2/g and zirconium titanate showed very low dielectric loss(4 × 10 −4).

Combustion synthesis of fine-particle ceria

Fine-particle ceria having narrow size distribution is of interest as polishing material for ophthalmological lenses, television tubes, plates and mirrors [1]. The preparation has been reported of such ceria by the hydrolysis of cerium isopropoxide [2] and cerium nitrate [3, 4] followed by thermal decomposition, as well as by the thermal decomposition of cerium oxalate hydrazinate [5] and cerium hydrazine carboxylate [6]. In this letter we report the preparation of fine-particle, large-surface-area ceria by the combustion process developed for the preparation of $\alpha$-alumina [7], aluminates [8], chromites [9] and ferrites [10]. The process involves rapid decomposition of a saturated aqueous solution containing ceric ammonium nitrate and urea $(CH_4N_20)$, carbohydrazide $(CH_6N_4O (CH))$, oxalyl dihydrazide $(C_2H_{16}N_4O_2 (ODH))$ or tetraformal trisazine $(C_4H_{16}N_6O_2 (TFTA))$ redox mixtures.

Synthesis, characterisation and thermal analysis of copper (II) and chromium (II, III) hydrazine carboxylates

Copper(II) hydrazine carboxylate monohydrate, Cu(N2H3COO)2·H2O and chromium (II, III) hydrazine carboxylate hydrates, Cu(N2H3COO)2·H2O and Cu(N2H3COO)2·3H2O have been prepared and characterised by chemical analysis, IR, visible spectra and magnetic measurements. Thermal analysis of the copper complex yields a mixture of copper metal and copper oxide. Chromium complexes on thermal decomposition yield Cr2O3 as residue. Decomposition of chromium(HI) complex under hydrothermal conditions yield CrOOH, a precursor to CrO2.