Nicotinic Hydrazide Research Articles

Ionic Organic Network-based C3-symmetric@Triazine core as a selective Hg+2 sensor

ABSTRACT The C3-symmetry ionic polymer PPyTri has been designed with multi-walled carbon nanotubes (MWCNTs) or graphene nanoplatelets (GNPs) and studied as an ultrasensitive electrochemical sensor for trace Hg(II) detection. The synthesis approach incorporated attaching three pyridinium cationic components with chloride anions to the triazine core. The precursors, BPy, were synthesized using a condensation process involving 4-pyridine carboxaldehyde and focused nicotinic hydrazide. The polymer PPyTri was further modified with either MWCNTs or GNPs. The resulting ionic polymer PPyTri and its fabricated nanocomposites were characterized using infrared (IR), nuclear magnetic resonance (NMR), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and powder X-ray diffraction (XRD). The analysis revealed that both the polymer and its nanocomposites have semi-crystalline structures. The electroactivity of the designed nanocomposites toward Hg + 2 ions revealed that among the nanocomposites and bare copolymer, the glassy carbon electrode (GCE) adapted with the PPyTri GNPs-5% exhibited the greatest current response over a wide range of Hg + 2 concentrations. The nanocomposite-modified electrode presented an excellent sensitivity of 83.33 µAµM − 1 cm − 2, a low detection limit of 0.033 nM, and a linear dynamic range of 0.1 nM to 0.01 mM (R2 = 0.9945).

Synthesis, characterization, DFT studies and evaluation of the potential anti-tumour activity of nicotinic hydrazide based Schiff base using in vitro and molecular docking techniques

Breast cancer, one of the most serious issues worldwide, has been raising day by day. It has now become a necessary to develop a suitable drug to combat this terrible illness. Schiff bases are increasingly being used as powerful medications for a number of illnesses. BNH has now synthesized from Benzil and Nicotinic hydrazide and characterized experimentally by FT-IR, UV, 1H NMR,13CNMR and Mass analysis. DFT calculations were done using Gaussian 16 W with B3LYP/6-311 + G (d,p) and geometry of the compound is optimized. Frontier Molecular orbit (FMO), Mullikan atomic charges and Molecular Electrostatic Potential (MEP) were studied. Invitro antimicrobial studies were done using various bacteria and fungi. The synthesized compound is appropriate against bacterial and fungal actions. Invitro study were done using MCF-7 cell lines to analyze the anticancer property of the ligand. The outcome suggests that BNH may be employed in the future as a novel anticancer medication.

Synthesis of Novel Hydrazide-Hydrazone Compounds and In Vitro and In Silico Investigation of Their Biological Activities against AChE, BChE, and hCA I and II.

The abnormal levels of the human carbonic anhydrase isoenzymes I and II (hCA I and II) and cholinesterase enzymes, namely, acetylcholinesterase (AChE) and butyrylcholinesterase (BChE), are linked with various disorders including Alzheimer's disease. In this study, six new nicotinic hydrazide derivatives (7-12) were designed and synthesized for the first time, and their inhibitory profiles against hCA I, hCA II, AChE, and BChE were investigated by in vitro assays and in silico studies. The structures of novel molecules were elucidated by using spectroscopic techniques and elemental analysis. These molecules showed inhibitory activities against hCA I and II with IC50 values ranging from 7.12 to 45.12 nM. Compared to reference drug acetazolamide (AZA), compound 8 was the most active inhibitor against hCA I and II. On the other hand, it was determined that IC50 values of the tested molecules ranged between 21.45 and 61.37 nM for AChE and between 18.42 and 54.74 nM for BChE. Among them, compound 12 was the most potent inhibitor of AChE and BChE, with IC50 values of 21.45 and 18.42 nM, respectively. In order to better understand the mode of action of these new compounds, state-of-the-art molecular modeling techniques were also conducted.

Preparative and Catalytic Properties of MoVI Mononuclear and Metallosupramolecular Coordination Assemblies Bearing Hydrazonato Ligands.

A series of polynuclear, dinuclear, and mononuclear Mo(VI) complexes were synthesized with the hydrazonato ligands derived from 5-methoxysalicylaldehyde and the corresponding hydrazides (isonicotinic hydrazide (H2L1), nicotinic hydrazide (H2L2), 2-aminobenzhydrazide (H2L3), or 4-aminobenzhydrazide (H2L4)). The metallosupramolecular compounds obtained from non-coordinating solvents, [MoO2(L1,2)]n (1 and 2) and [MoO2(L3,4)]2 (3 and 4), formed infinite structures and metallacycles, respectively. By blocking two coordination sites with cis-dioxo ligands, the molybdenum centers have three coordination sites occupied by the ONO donor atoms from the rigid hydrazone ligands and one by the N atom of pyridyl or amine-functionalized ligand subcomponents from the neighboring Mo building units. The reaction in methanol afforded the mononuclear analogs [MoO2(L1-4)(MeOH)] (1a-4a) with additional monodentate MeOH ligands. All isolated complexes were tested as catalysts for cyclooctene epoxidation using tert-butyl hydroperoxide (TBHP) as an oxidant in water. The impact of the structure and ligand lability on the catalytic efficiency in homogeneous cyclooctene epoxidation was elucidated based on theoretical considerations. Thus, dinuclear assemblies exhibited better catalytic activity than mononuclear or polynuclear complexes.

Synthesis and Characterization of Co(II), Ni(II), Cu(II) and Zn(II) Complexes with N'-( phenyl ( pyridin-2-yl)methylene)Nicotinohydrazide

The Schiff base (HL), derived from 2-benzoylpyridine and nicotinic hydrazide, and its complexes with some metal transition (Co, Ni, Cu, Zn) have been synthesized. These compounds have been characterized by means of elemental analysis, 1H and 13C NMR (for HL), FTIR spectroscopy, UV–Vis spectroscopy, molar conductance and room temperature magnetic measurements. The compounds are found isostructural and are formulated as {[Co(L)2].2H2O} (1), {[Ni(L)2].2H2O} (2). {[Cu(L)2].3H2O} (3). {[Zn(L)2].H2O} (4). The two ligand molecules act in their monodeprotonated forms through one azomethine nitrogen atom, one pyridine nitrogen atom and one iminolate oxygen atom yielding six coordinate metal center. The complex 4 crystallizes in the monoclinic space group P21 with cell parameters of a = 9.3429(8) A, b = 10.3034(9) A, c = 16.6349(14) A, β = 101.109(4)°, V = 1571.3(2) A3, Z = 2, R1 = 0.027, wR2 = 0.074. The zinc atom is six-coordinated, and the coordination polyhedron is best described as a distorted octahedral geometry. The aromatic rings of the ligand molecules are twisted each other with dihedral angle values in the range 10.168(2)°–74.430(1)°.

Transition metal complexes of N'-(2-cyanoacetyl)nicotinohydrazide: Synthesis, structural and anticancer activity studies

On reacting the nicotinic hydrazide with 1-cyanoacetyl-3,5-dimethylpyrazole, a new ligand, N'-(2-cyanoacetyl)nicotinohydrazide (H2L), was produced and characterized using diverse spectral studies which cleared out that the free ligand existed in keto form. The ligand reacted with Cu(II), Co(II), Ni(II) and Zn(II) acetates affording metal complexes with 1:1 (M:L) stoichiometric which was validated using the elemental and mass spectral measurements. The spectral studies of the isolated complexes showed that the ligand chelated to metal ion in mononegative bidentate fashion via the amide nitrogen and deprotonated enolized carbonyl oxygen group. Moreover, the DFT quantum chemical calculations indicated that the ligand has the highest HOMO-LUMO energy gap, ΔEH-L, while the Co(II) complex has the lowest and may be sorted as H2L > Zn(II) > Cu(II) > Ni(II) > Co(II). Furthermore, isolated compounds’ in vitro cytotoxic activity against HePG-2 and HCT-116 cell lines was investigated and the data cleared that the ligand has very strong, IC50 6.59 ± 0.4 and 8.17 ± 0.7 μM, respectively. Whereas, the metal complexes exhibited moderate to weak potent effect against both cell lines.

Molecular recognition of carbonate ion using a novel turn-on fluorescent probe

A novel turn-on fluorescent probe 3 was synthesized by condensing salicylaldehyde and nicotinic hydrazide for the selective detection of CO32– in aqueous medium. Probe 3 exhibited a turn-on fluorescence response toward CO32– with excellent selectivity, sensitivity (DL = 2.76 μM), and good reversibility. The binding constant (K) of probe 3 with CO32– was calculated to be 5 × 103 M−1 (log K 3.69). The 1:1 stoichiometry of the complex between probe 3 and CO32– ions was confirmed by Job's plot and ESI-MS spectra. Deprotonation and hydrogen-bonding interactions are involved in the recognition of CO32– ion, which was also suggested by 1H NMR, ESI-MS spectra, and Density Functional Theory (DFT) calculations. Moreover, an INHIBIT type molecular logic gate was constructed by using 3:CO32– and CH3COOH as inputs and current signal as output. Owing to the practical applications, probe 3 demonstrated its efficiency in quantifying CO32– ion in real water samples through standard addition method, thus showcasing its potential in real environment. Further, the MTT assay indicated very low cytotoxicity (IC50 = 1 mM) of probe 3 and also the cell imaging experiments demonstrated the effective sensing of CO32– ions with probe 3 in the biological systems.

Excited state dynamics of 1,2,4-triazolyl-thio-pentane-2,4-dione system and their conversion to biologically active novel triazole-S-pyrazole hybrids

The current study focuses on designing and synthesis of novel 1,2,4-triazole appended pyrazoles linked to each other through sulphur atom. Herein we report the condensation of nicotinic hydrazide and isonicotinic hydrazide with aryl isothiocyanate derivatives to obtain carbothioamides which are cyclised to yield 4-aryl-5-(pyridinyl)-2,4-dihydro-3H-1,2,4-triazole-3-thione derivatives under alkaline conditions. Further, condensation of thiones with 3-chloro-pentane-2,4-dione generated novel 1,2,4-triazolyl-thio-pentane-2,4-dione system which was studied for keto-enol tautomerism with the help of spectral data (FT-IR, NMR and Mass). Low energy barrier between three different tautomers (chelated enol, keto, non-chelated enol) resulted in transformation of chelated enol ⇌ non-chelated enol ⇌ keto form upon UV-irradiation. Solvent effects on excited state intramolecular proton transfer (ESIPT) in dione 5a have been studied and the experimental findings were documented with TD-DFT studies. The generated 1,3-diketones were treated with hydrazine hydrate to obtain triazolyl-S-pyrazole hybrids 6. Structure of the synthesized compounds was identified on the basis of spectroscopic data. Single crystal X-ray diffraction (SC-XRD) studies of the representative compound 6a predicts the strong intermolecular hydrogen bonding interaction between N2H2 of pyrazole ring of one molecule and N4 of triazole ring (N2H2…N4) of the other molecule which accounts for the crystal stability. Moreover, triazolyl-S-pyrazole hybrids were also assessed for their antibacterial activities and some derivatives have shown promising activity against E. coli.

Bivalent Metal Chelates with Pentadentate Azo-Schiff Base Derived from Nicotinic Hydrazide: Preparation, Structural Elucidation, and Pharmacological Activity.

Azo-Schiff base ligand (N'-((E)-2-hydroxy-5-((E)-(2-hydroxyphenyl)diazenyl)benzylidene)nicotinohydrazide) and its Mn(II), Co(II), Ni(II), Cu(II), Zn(II) and Pd(II) chelates were prepared and elucidated. The geometrical structures of the prepared chelates were characterized by several spectroanalytical techniques and thermogravimetric analysis. The obtained data revealed that the chelates have (1M:1L), (1M:2L), (1M:3L), and (1M:4L) molar ratios. The infrared spectra displayed that the H2 L ligand behaves in a pentacoordinate fashion in chelates of Mn(II), Ni(II), and Cu(II) ions. However, in Zn(II) and Pd(II) chelates, the ligand is coordinated as a tetradentate species (NONO) through nitrogen atoms of azomethine and azo groups as well as oxygen atoms of phenolic hydroxy, and carbonyl groups. Besides, it was concluded that the oxygen atoms of carbonyl and hydroxy groups along with the azomethine nitrogen atom of the ligand are bounded with Co(II) ion in metal chelate (2). According to the measured molar conductance values, the chelates of Cu(II), Zn(II), and Pd(II) are weak electrolytes, but Mn(II), Co(II), and Ni(II) chelates are ionic. The azo-Schiff base ligand and its prepared metal chelates were tested for their antioxidant and antibacterial properties. The Ni(II) chelate was found to be considered an effective antioxidant agent. In addition, the available antibacterial data suggest that the Ni(II) and Co(II) chelates may be employed as inhibitor agents against Proteus vulgaris, Escherichia coli, and Bacillus subtilis bacteria. Furthermore, the data showed that, in comparison to the ligand and other metal chelates, copper(II) chelate (4) exhibited higher action against Bacillus subtilis bacteria.

Synthesis, structures, and gas adsorption properties of Hg(II) and Cd(II) complexes constructed from two acylhydrazone ligands with multiple coordination sites

Two chain-like acylhydrazone ligands (L1 and L2) were synthesized from Schiff base condensation reaction of 3,3′-(1,4-piperazine-bis-(methylene)-bis-(2-hydroxy-5-methylbenzaldehyde)) (b) with isonicotinic hydrazide or nicotinic hydrazide, respectively. In the presence of Hg(II) or Cd(II) ions and in DMF/methanol solution, three complexes, formulated as {[Hg3L1Br6]·4DMF}n (1), {[Hg2L2I4]·2DMF}n (2), and [Cd4(L2)2I8(H2O)2]·4DMF (3), were synthesized and further characterized via elemental analysis, FT-IR spectra and single-crystal X-ray diffraction. Complex 1 exists as a 1D zag-zig chain polymer and complex 2 exists as a 1D looped chain polymer. Complex 3 exists as a rare tetranuclear structure. The structural differences of the three complexes and the coordination competition among the coordination sites were analyzed, and the results showed that the pyridyl nitrogen atoms have an obvious coordination ability prior to other sites. Furthermore, gas adsorption measurements were carried out, which show that the three complexes exhibit good adsorption capacity towards CH3OH over N2, H2, O2, and CO2.

Spectroscopic Studies and X-ray Structural of Dinuclear Lanthanide (III) Complexes Derived from N'-(2-hydroxy-3-methoxybenzylidene) Nicotinohydrazide

Two Schiff bases (H₂L), derived from o-vanillin and nicotinic hydrazide, and its complexes with some lanthanides (Y, Ce, Yb, Pr, Gd and Tb) have been synthesized. These compounds have been characterized by means of elemental analysis, UV–Vis spectroscopy, FTIR spectroscopy, ¹H and ¹³C NMR (for H₂L), molar conductance and room temperature magnetic measurements. The compounds are found isostructural and are formulated as {[(Z)(<i>η</i>²-OOCH₃)Ln](<i></i>-L)₂[Ln(<i>η</i>²-OOCH₃)(Z)]} (Z = H₂O for Ln = Y, Ce, Pr, Gd or Tb and Z = OS(CH₃)₂for Ln =Yb). The two ligand molecules act in their dideprotonated forms through one azomethine nitrogen atom, one phenoxo oxygen atom and one iminolate oxygen atom. The two Ln (III) ions are bridged by two phenoxo oxygen atoms, forming a dinuclear complex. Single crystal X-ray analysis of the ytterbium complex has revealed the nature of the structure {[(OS(CH₃)₂)(<i>η</i>²-OOCH₃)Yb](<i></i>-L)₂[Yb(<i>η</i>²-OOCH₃)(OS(CH₃)₂)]} (3). The complex crystallizes in the monoclinic space group C2/c with cell parameters of <i>a</i> = 13.0391(6) Å, <i>b</i> = 15.1199(6) Å, <i>c</i> = 20.7239(7) Å, <i>β</i> = 105.671(2)°, <I>V</I> = 3933.8(3) ų, <I>Z</I> = 4, <I>R</I>₁ = 0.025, <i>wR</i>₂ = 0.65. The ytterbium atoms are eight-coordinated, and their coordination polyhedron are best described as a square antiprismatic geometry. The aromatic rings of the ligand molecule are twisted with dihedral angle of 29.23 (1)° between their mean planes.

Twisted intramolecular charge transfer, nonlinear optical, antibacterial activity, and DFT analysis of ultrasound processed (E)-N′-(4-isopropylbenzylidene)nicotinohydrazide

Hydrazones have attracted considerable interest for their antimicrobial and nonlinear optical (NLO) applications. In the present work, a new hydrazone (E)-N′-(4-isopropylbenzylidene)nicotinohydrazide (INH) was synthesized by a condensation reaction of cuminaldehyde with nicotinic hydrazide via ultrasonication. The hydrazone was characterized by FT-IR spectroscopy, mass spectrometry, NMR (1H, 13C, HOMO-COSY, HSQC, and DEPT-135), elemental analysis, and FESEM analyses. Phase-pure and non-existent isomorphic phase transition in INH was demonstrated by X-ray diffraction and thermogravimetric analysis. The absorption maximum of INH in an aqueous solution was red-shifted compared to that of the reactant molecules, indicating that the CN bond formation efficiently enhances the resonance interaction towards the pyridine ring. Fluorescence emission of INH at a shorter wavelength is caused by a locally excited state. A longer wavelength band is caused by intramolecular proton transfer in nonpolar/aprotic solvents, while it is caused by TICT emission in protic solvents. The direct and indirect bandgaps of the INH crystals were assessed using Tauc plots and the Kubelka–Munk algorithm. The efficacy of INH for the inactivation of E. coli and B. subtilis were examined through a plate colony counting assay, and the inactivation was 62.7 ± 0.2 % and 98.3 ± 0.4 %, respectively. The geometrical structure, Mulliken, MEP surface, and electronic properties of INH are theoretically optimized using density functional theory (DFT) at the B3LYP/6-31G(d,p) level and showed good concurrence with the experimentally defined structure. The INH displays higher NLO properties compared to urea as a reference, as determined by molecular hyperpolarizability analysis. The frontier molecular orbitals and global reactivity descriptors showed that INH is more reactive and reasonably stable.

DESIGN AND SYNTHESIS OF SOME ARYLHYDRAZONE DERIVATIVES AS POTENTIAL FAAH INHIBITORS

Objective: The aim was to design, synthesis and investigation of possible interactions in the enzyme active site of a series of arylhydrazone derivatives for the inhibition of the FAAH enzyme. Material and Method: Arylhydrazone derivatives were obtained through the reaction of nicotinic hydrazide or benzohydrazide with appropriate aldehyde derivatives, and the obtained crude product was recrystallized from ethanol. After elucidating chemical structures of the compounds via spectroscopic methods, the inhibitory activities against hFAAH were screened. The results were further supported with molecular modeling studies. Result and Discussion: In this study, a new series of seven arylhydrazone derivatives were screened against hFAAH. 4-phenoxyphenyl bearing derivative 5 was found to inhibit hFAAH 40 % at 10 µM which indicates that newly developed inhibitor could serve as a starting point for improving inhibitory effect of the new series.

Silica-coated nanomagnetite-supported oxovanadium(V) Schiff base complex: Preparation, characterization, and catalytic application for the oxidation of sulfides

In this paper, an oxovanadium(V) complex, prepared with a tridentate ONO Schiff base by reacting nicotinic hydrazide with 3-methoxysalicylaldehyde, was immobilized on the surface of the silica-coated magnetite nanoparticles. After successful preparation and complete characterization (FT–IR, SEM, XRD, TEM, VSM, EDX, and ICP), the catalytic activity of the magnetic organic–inorganic nanocomposite was explored for the green oxidation reaction of different kinds of aryl and alkyl sulfides employing hydrogen peroxide and methanol under reflux conditions. Significant features such as simple work-up, fast reaction, higher product yield, and reusability of the catalyst enhance the efficiency of this catalytic procedure economically and environmentally.

Hidrazon Türevi Yeni Fe(II), Co(II), Ni(II) ve Cu(II) Komplekslerinin Sentezi ve Karakterizasyonu

2-hidroksinaftaldehit ile nikotinik hidrazit'in kondenzasyon reaksiyonundan N-((2-hidroksinaftalen-1-il)metilen)nikotinohidrazit ligandı elde edilmiştir. N-((2-hidroksinaftalen-1-il)metilen)nikotinohidrazit ligandı ile Fe(II), Co(II), Ni(II) ve Cu(II) asetat tuzlarının (2:1) reaksiyonundan yeni hidrazon metal L2Fe, L2Ni, L2Co ve L2Cu2 kompleksleri sentezlenmiştir. Sentezlenen bileşikler FT-IR, NMR (sadece ligand), UV-Vis, elementel analiz, molar iletkenlik ölçümü, manyetik duyarlılık gibi tekniklerle karakterize edilmiştir. Manyetik duyarlılık ölçümleri L2Fe, L2Co L2Ni ve L2Cu2 kompleksleri için sırasıyla 5.96 BM, 1.03 BM, 1.08 BM ve 1.61 BM olarak kaydedilmiştir. L2Cu2, L2Ni ve L2Co komplekslerinin antiferromanyetik özellikte olduğu belirlenmiştir. L2Fe, L2Co ve L2Ni kompleksleri oktahedral, L2Cu2 kompleksi ise kare düzlem geometriye sahiptir. Komplekslerin molar iletkenlik değerleri 1.31-2.61 μS/cm arasında olup, iletkenlik özelliği taşımamaktadır.

Mechanistic studies on the oxidation reaction of antitubercular drug isoniazid and its analogy hydrazides by chlorine dioxide over a wide pH range

Oxidations of the antitubercular drug isoniazid (INH) and its analogy hydrazides, nicotinic hydrazide (NH), picolinoyl hydrazide (PH), and benzohydrazide (BH), by ClO2 were investigated with a focus on the kinetics and reaction mechanisms. In buffered solutions of a wide pH range (from 0.51 to 10.35), the oxidation reactions strictly followed the second-order kinetics, and the apparent second-order rate constant kapp versus pH profiles were established at 25.0 °C and 1.0 M ionic strength. Excess ClO2 could rapidly oxidize the hydrazides to their corresponding aryl acids which were identified by mass spectrometry. For each of the hydrazides, the proposed reaction mechanism involves parallel rate-determining reactions between ClO2 and various protolysis species of the hydrazide, rendering two types of hydrazyl free radicals; the free radicals are quickly oxidized by 3 more equivalents of ClO2 to aryl acids. The derived rate constants for the rate-determining reactions revealed that for each hydrazide a huge reactivity difference existed among the protolysis species (>108 times) and that the enolate form (or its resonant structures) was extremely reactive. Two possible modes of electron transfer in the rate-determining reactions are discussed based on the observed reaction characters. In buffered solution of pH 7.0 and 25.0 °C, the measured values of kapp are 6.20×104, 7.8×103, 2.57×103, and 1.83×103 M−1 s−1 for INH, NH, PH, and BH, respectively, imparting an important data set as a reference to the water treatment. This work may open a new door for resolving water pollution caused by INH and its derivatives.

A new Ruthenium(II) sensitizer with anchored hydrazide ligand for enhanced electron injection in dye sensitized solar cell application

This work highlights the synthesis ofnew Ruthenium(II) sensitizer (RNIHFB) constructed with Nicotinic hydrazide as ligand and characterized by various analytical and spectroscopic techniques. Coordination mode of the ligand (NIHFBA=(E)-4-((2-nicotinoyl hydrazono)methyl)benzoic acid) was explored by vibrational spectra in which the ligand serves as bidentate to ruthenium central metal ion. HOMO, LUMO and molecular structures of the NIHFBA and RNIHFB were optimized using quantum chemical calculation. Acid group (–COOH) present in the NIHFBA acts both as anchoring unit and as a good electron acceptor and has excellent electron-withdrawing capability. The sensitizer has small energy gap 2.180 eV and high thermal stability up to 284 °C. Dye containing bi-anchoring groups shows better electronic coupling with TiO2 than mono anchoring group. The new RNIHFB fabricated DSSC uttered a general photoconversion competence (η) of 4.17% with Voc of 0.88 V.

Synthesis, spectral characterization, chemical reactivity and anticancer behaviors of some novel hydrazone derivatives: Experimental and theoretical insights

In this research, two new hydrazone derivatives; namely compound 1 (N'-(4-((2-hydroxyethyl)(methyl)amino) benzylidene)nicotinohydrazide) and compound 2 (N'-(4-((2-hydroxyethyl)(methyl)amino) benzylidene)isonicotinohydrazide), were designed, successfully synthesized with high purity by treatment of N-methyl-N-(2-hydroxyethyl)-4-aminobenzaldehyde with nicotinic hydrazide and isoniazid, respectively. Spectroscopic characterization of the synthesized compounds was carried out by using FT-IR, UV–Vis, HRMS, 1H- and 13C- NMR spectroscopic techniques, and elemental analysis (C, H, N). For the synthesized compounds, important quantum chemical parameters like frontier orbital energies, hardness, softness, chemical potential, back-donation energy, first electrophilicity index, second electrophilicity index, electrodonating power, electroaccepting power were calculated and the relations with the chemical stability of these parameters were discussed as detailed. Additionally, anticancer properties of the mentioned compounds were analyzed with the help of Molecular Docking studies.

Comparative spectral (FT-IR, FT-Raman, UV) investigations, HOMO–LUMO, NBO and in-silico docking analysis of Nikethamide, niazid and 2-Mercaptonicotinic acid

The FT-IR and FT-Raman spectra of N, N-Diethylnicotinamide (ENA), Nicotinic Hydrazide (NHD) and 2-Mercaptonicotinic acid (MNA) were recorded and analyzed experimentally and theoretically. The complete vibrational assignments for all the vibrational modes have been supported by normal coordinate analysis and potential energy distributions. The equilibrium geometry, natural bond orbital calculations and vibrational assignments have been carried out using density functional B3LYP method with the 6–311G++(d,p) basis set. In addition, TD-DFT calculation is initiated to simulate the UV–Vis absorption spectrum and to determine several important electronic properties like HOMO-LUMO gap energy and electronic transitions. In-silico studies have been used to analyze the drug likeness and de-addiction property of the title compounds. The antibacterial activities of the title compounds have been studied via molecular docking and QSAR analysis. Moreover, the title compounds ENA (18.2, 161.9 μm) and NHD (75.11, 54.02 μm) showed a greater inhibiting ability than MNA (80.5, 122.08 μm) when docked against the proteins (PDB ID: 2H29 and 3NM8) and the QSAR analysis proved that the studied compounds have an inhibitor effect against bacterial diseases.

PREPARATION, CHARACTERIZATION AND ANTIBACTERIAL STUDIES OF HYDRAZONE SUBSTITUTED MOLYBDENUM CARBONYLS

The hydrazones; (E)-N'-(3-methoxybenzylidene)nicotinohydrazide (ANH) and (E)-N'-(2-hydroxybenzylidene)isonicotinohydrazide (SIH) were prepared by condensation reaction between either m-anisaldehyde or salicylaldehyde with nicotinic hydrazide and isoniazid respectively. Substituting CO in Mo hexacarbonyl with the hydrazones in the presence of trimethylamine N-oxide as decarbonylating agent at ambient temperature under inert atmosphere produced tricarbonyl constituents. The complexes were characterized via spectroscopic techniques, elemental analysis and evaluated for antibacterial mode and action. FTIR/Raman, 1H and 13C MMR spectra obtained revealed that three CO were substituted for hydrazones in the hexacarbonyl, consistent with CHN elemental analysis. The ancillary ligands coordinate through the pyrimidine nitrogen to the Mo centre in a meridional geometry; Mo(CO)3(ANH)3 and Mo(CO)3(SIH)3. The coordination mode afforded a fairly stable complex which released CO in DMSO with release rate of 1.9 × 10-3 and 1.07 × 10-2 kCO) s-1. Examination of compounds ability to release CO to myoglobin under physiological pH revealed that carbonmonoxyhemoglobin was spontaneously formed at 3 to 4 seconds of introduction of the complexes. Antibacterial action against both Gram-negative and -positive bacteria revealed that Mo(CO)3(ANH)3 shows both bacteriostatic and bactericidal action against E coli, S. aureus and P. aeruginosa with activity comparable to the ampicillin control. The Mo(CO)3(SIH)3 analogue was however not effective in inhibiting the growth of the organisms at concentrations below 1000 µM . The methoxy and hydroxyl group on the ligand is suspected to account for the differences in action. The hydrophilic hydroxyl group in Mo(CO)3(SIH)3 can hinder it cell wall penetrating ability compared to the lipophilic group present in Mo(CO)3(ANH)3.