Acetic Acid Hydrazide Research Articles

Design, Synthesis, and Antimicrobial Evaluation of Novel Schiff Bases Derived from Thymol

Schiff bases, a significant class of organic compounds, are synthesized through the reaction of a primary amine with an aldehyde or ketone under specific conditions. In this study, we report the synthesis of novel Schiff bases derived from thymol (2-Isopropyl-5-methylphenol). The synthesis began with the esterification of thymol to produce (2-Isopropyl-5-methylphenoxy)-acetic acid ethyl ester (1), followed by hydrazination to yield (2-Isopropyl-5-methylphenoxy)-acetic acid hydrazide (2). The hydrazide (2) was then treated with various aromatic aldehydes to synthesize a series of Schiff bases (3A-J). The chemical structures of these compounds were elucidated using infrared (IR) spectroscopy, proton nuclear magnetic resonance (1H-NMR), and mass spectrometry. The synthesized Schiff bases were evaluated for their antibacterial and antifungal activities using standard screening methods. The results indicated that all synthesized compounds exhibited varying degrees of antimicrobial activity. Among the series, compound 3C showed the highest antibacterial and antifungal potency, suggesting it could be a promising candidate for further development. This study highlights the potential of Schiff bases as bioactive compounds with broad-spectrum antimicrobial properties. The structure-activity relationship (SAR) suggests that the presence of specific substituents on the aromatic aldehyde moiety could enhance biological activity. Further investigation into the mechanisms of action and optimization of these Schiff bases could contribute to the development of novel antimicrobial agents

Design, Synthesis, and Antiviral and Fungicidal Activities of 4-Oxo-4H-quinolin-1-yl Acylhydrazone Derivatives.

To discover novel antiviral agents, based on the high antiviral activity of (4-oxo-4H-quinolin-1-yl)-acetic acid hydrazide (C), a series of 4-oxo-4H-quinoline acylhydrazone derivatives were designed, synthesized, and first evaluated for their antiviral and fungicidal activities. Most acylhydrazone derivatives exhibited moderate to good antiviral activities in vivo. The inactive, curative, and protective activities of compounds 4 (51.2, 47.6, and 46.3%), 11 (49.6, 43.0, and 45.2% at 500 mg/L), and 17 (47.1, 49.2, and 44.1%) were higher than those of ribavirin (39.2, 38.0, and 40.8%) at 500 mg/L. Molecular docking showed that compound 4 exhibited a stronger affinity to TMV coat protein (TMV-CP) than ribavirin, with a binding energy (-6.89 kcal/mol) slightly lower than that of ribavirin (-6.08 kcal/mol). Microscale thermophoresis showed that compound 4 (K d = 0.142 ± 0.060 μM) exhibited a strong binding ability to TMV-CP, superior to that of ribavirin (K d = 0.512 ± 0.257 μM). The results of transmission electron microscopy showed that compound 4 hindered the self-assembly and growth of TMV. The antifungal activities of most compounds were moderate at 50 mg/L, among which compounds 12 and 21 exhibited a 72.1 and 76.5% inhibitory rate against Physalospora piricola, respectively. Meanwhile, compound 16 exhibited a 60% inhibitory rate against Cercospora arachidicola Hori at 50 mg/L.

The Nurr1 ligand indole acetic acid hydrazide loaded onto ZnFe2O4 nanoparticles suppresses proinflammatory gene expressions in SimA9 microglial cells

The nuclear receptor-related factor 1 (Nurr1), an orphan nuclear receptor in microglia, has been recognized as a major player in attenuating the transcription of the pro-inflammatory genes to maintain CNS homeostasis. In this study, we investigate Nurr1 trans-repression activity by targeting this receptor with one of the indole derivatives 3-Indole acetic acid hydrazide (IAAH) loaded onto zinc iron oxide (ZnFe2O4) NPs coated with PEG. XRD, SEM, FTIR, UV–Vis spectroscopy, and DLS were used to characterize the synthesized IAAH-NPs. The anti-inflammatory properties of IAAH-NPs on LPS-stimulated SimA9 microglia were assayed by measuring pro-inflammatory cytokine gene expressions and protein levels using RT-PCR and ELISA, respectively. As a result, IAAH-NPs showed an ability to suppress pro-inflammatory genes, including IL-6, IL-1β, and TNF-α in LPS-stimulated SimA9 via targeting Nurr1. The current study suggests that ZnFe2O4 NPs as a delivery system can increase the efficiency of cellular uptake and enhance the IAAH ability to inhibit the pro-inflammatory cytokines. Collectively, we demonstrate that IAAH-NPs is a potential modulator of Nurr1 that combines nanotechnology as a delivery system to suppress neuroinflammation in CNS which opens a window for possible ambitious neuroprotective therapeutic approaches to neuro disorders.

Evaluation of vanadium coordination compounds derived from simple acetic acid hydrazide as non-conventional semiconductors

Vanadium(v) complexes prepared from acyl-hydrazones were obtained. The structural transformations were observed by applying in situ impedance spectroscopy, while electrical characteristics were correlated with thermal and structural properties.

Investigation of transition metal chelates with a ligand (3-cyano-6-thiophen-2-yl[4,4′]bipyridinyl-2-yloxy)-acetic acid hydrazide as corrosion inhibitors for copper in 1.0 M HCl solution

Mn(II), Fe(III),Co(II), Ni(II) and Cu(II) complexes of the ligand named (3-Cyano-6-thiophen-2-yl[4,4′]bipyridinyl-2-yloxy)-acetic acid hydrazide (abbreviated as HL) have been synthesized. Structure assignment of such chelates have been performed by means of analytical and spectral tools which joint assured the formulation of the chelates in 1 M: 1 L ratio with non-electrolytic character for all the complexes. Fe(III) complex is 1:3 electrolyte. The spectral IR toll proved the neutral tridentate ligand nature connecting to the metal ions by the azomethine nitrogen, carbonyl and ester oxygen atoms. Octahedral structure has been concluded for all the isolated chelates as deduced from the UV-Vis spectral analysis. The investigated complexes were tested to protect or restrain the corrosion of copper in 1.0 M HCl solution at 298 K using different techniques. The outcomes being acquired illuminated that the synthesized compounds were discovered to be efficient inhibitors and their % IEs were concluded to be dependent on both concentrations and structures. The order of the % IEs of the tested compounds was: HL-Mn> HL-Fe> HL-Co ≥ HL- Ni> HL-Cu> HL. The acquired high % IEs were ascribed to the powerful adsorption of the organic molecules on the surface of copper which was agreed with Langmuir adsorption isotherm. The kinetics of corrosion inhibition by the examined compounds appeared negative-first order process. PDP results indicated that the complex HL-Mn behaves as a mixed-kind inhibitor with slight anodic seniority. The employed techniques used for the complex HL-Mn were in a good consistence with each other.

4-(3-Amino-4-mehoxy-5-methylphenyl)-1-oxo-1H-phthalaz-2-yl] acetic acid hydrazide and its synergetic effect with KI as a novel inhibitor for low carbon steel corrosion in 0.5 M H2SO4

We report the synthesis of novel [4-(3-amino-4-mehoxy-5-methyl phenyl)-1-oxo-1H-phthalaz-2-yl] acetic acid hydrazide (APPH), followed by its characterization using X-ray diffraction (XRD), Fourier transforms infrared (FT-IR) spectroscopy, 1H-NMR spectroscopy, and LC/MS. Further, the inhibition effect of the varying concentration of APPH on the corrosion of low steel (LCS) in 0.5 M H2SO4 was investigated by weight loss and electrochemical measurements at 30 °C. The percentage inhibition efficacy of APPH increased with concentration and reached about 84% at 0.5 mM at 30 °C, also rising to 88% after 6 h of exposure. According to the polarization measurements, the investigated APPH works as a mixed-type inhibitor. Furthermore, the synergistic corrosion inhibition mechanism APPH showed that the inhibition efficiency maximizes with increasing inhibitor concentration, and the maximum value was 83% at 0.5 mM APPH. The adsorption of APPH on the LCS surface is more fitting to the Langmuir isotherm model. The free energy value (–ΔG° ads) was 33.3 kJ mol−1. Quantum chemical calculation was applied to APPH and acted as excellent support for the experimental data.

Synthesis of pyrimidine linked heterocyclic scaffolds by intramolecular cyclization and study of biological potential

Synthesis of some interesting pyrimidine linked heterocyclic scaffolds by intramolecular cyclization has been worked out. Initially compound (4,6-dimethyl-pyrimidin-2-yl-amino)-acetic acid hydrazide has been prepared by reacting 2-amino-4,6-dimethyl pyrimidine with ethyl chloroacetate, followed by condensation with hydrazine hydrate. It has then been treated with N-aryl/alkyl isothiocyanates, followed by intramolecular cyclization using alkaline ethanolic solution of I2 with KI, o-phosphoric acid and aqueous KOH to afford respective heterocyclic compounds with differently substituted pharmacophores viz. (5-aryl/alkyl-amino-[1,3,4]-oxadiazol-2-yl-methyl)-(4,6-dimethyl-pyrimidin-2-yl)-amines, (5-aryl/alkyl-amino-[1,3,4]-thiadiazol-2-yl-methyl)-(4,6-dimethyl-pyrimidin-2-yl)-amines and (4-aryl/alkyl-5-mercapto-[1,2,4]-triazol-3-yl-methyl)-(4,6-dimethyl-pyrimidin-2-yl)-amines. Developments during the synthesis have been monitored by TLC. Constitution of synthesized compounds have been delineated in accordance with equivalent weight, elemental assay,chemical transformation and IR, 1H NMR and mass spectral investigations. Title compounds have been tested for their biological potential.

Synthesis of hydrazides of heterocyclic amines and their antimicrobial and spasmolytic activity

Un unsolvable issue of a significant number increase of drug multi resistant strains of microorganisms including Mycobacterium tuberculosis force researchers for continuous design novel pharmaceuticals.The purpose of the study is the establishment of the correlation between the structure of novel heterocyclic hydrazide derivatives and their biological activity. Several hydrazide derivatives of N-piperidinyl and N-morpholinyl and propionic acids and N-piperidinyl acetic and their derivatives were synthesized via condensation of corresponding esters with hydrazine hydrate.The structure of synthesized compounds were confirmed by the use of FTIR, H1NMR, Mass-spectroscopy and element analysis. Investigation of synthesized substances using PASS software was carried out to predict probability of pharmacological activity in silico. The antibacterial, antifungal and spasmolytic activity as well as acute toxicity of obtained compounds were evaluated in vivo. 2-(N-piperidinyl)acetic acid hydrazide and 2-methyl-3-N-piperidinyl)propanacid hydrazide revealed antibacterial and spasmolytic activities comparable to the model drugs (drotaverin) in vitro study. Synthesized compounds in in vivo experiment showed significantly low acute toxicity (LD50 520–5750 mg/kg) compared to commercially available drugs (streptomicine, ciprofloxacinum and drotaverin LD50 100–215 mg/kg). The structure- activity relationship was established that the increasing of the length of the linker between heterocyclic amine and hydrazide group results in a decrease of antimicrobial activity against studied strains (Escherichia coli, Salmonella typhymurium, Salmonella choleraesuis, Staphylococcus aureus).

Synthesis of Phthalazinones with Amino or Hydrazide Moiety as Corrosion Inhibitors of Low Carbon Steel in 0.5 M H2SO4

Abstract[4‐(4‐methoxy‐3‐methyl‐5 amino phenyl)‐1(2H)‐phthalazinone (APP), and [4‐(4‐mehoxy‐3‐methyl phenyl)‐1‐oxo‐1H‐phthalaz‐2‐yl]acetic acid hydrazide (PPH) were synthesized as a novel independently corrosion inhibitor for carbon steel in 0.5 M H2SO4. Nuclear magnetic resonance, Fourier transform infrared and mass spectroscopy were used to validate the structure of the two anticorrosion compounds. The corrosion rate was studied by electrochemical methods (electrochemical impedance spectroscopy and potentiodynamic polarization) and gravimetric techniques, which clarify that the average corrosion inhibition efficiency of APP and PPH are 86 and 89 %, respectively. Impedance measurements showed that corrosion processes on the surface of LCS are controlled by a charge transfer mechanism. The PPH compound has a greater inhibitory effect on corrosion of low carbon steel. The quantum chemical calculations of APP and PPH were studied using AM1, PM3, and DFT/B3LYP/31G. Moreover, both APP and PPH acted as mixed type corrosion inhibitors. Adsorption of APP and PPH on low carbon steel (LCS) surface was physisorption and best fit to Langmuir isotherm.

Vibrational, electronic and reactivity insight on (5-chloro-benzofuran-3-yl)-acetic acid hydrazide: A Spectroscopic and DFT approach

Extensive quantum chemical calculation have been carried out to examine the Fourier Transform Infrared(FT-IR), Fourier Transform Raman(FT-Raman) and Nuclear magnetic resonance(NMR) spectra of (5-chloro-benzofuran-3-yl)-acetic acid hydrazide (5CBAH) molecule. The Gaussian computations have been carried out by DFT method using B3LYP/6-311++G (d, p) basis sets. The fundamental vibrational frequencies and intensities of the vibrational bands are analysed with the help of optimized structure. The theoretical NMR chemical shift values have been obtained using gauge independent atomic orbital (GIAO) method. The computed band gap energy of HOMO and LUMO depicts that charge transfer existed within the molecule. The internal molecular electronic interactions and their stabilizing energies are identified by the NBO analysis. The MEP map analysis is conducted to determine the chemical reactive site of the molecule. The thermodynamic properties of the title compound are studied for different temperatures. Non-linear optical properties and Fukui activity are also performed. The electron distribution and reactive site on the surface of the molecule are analyzed using ELF and LOL analysis. Atoms in Molecule (AIM) analysis is used to study the nature of interactions in molecular structure and to categorize and recognize the bonding interactions on the basis of quantum mechanical properties. The noncovalent interaction (NCI) analysis provides the most important interaction information's such as van der Waals interactions, hydrogen bonds and steric interactions present in the molecule.

Thermochemistry, Bond Energies and Internal Rotor Potentials of Acetic Acid Hydrazide, Acetamide, N-Methyl Acetamide (NMA) and Radicals

Structures, thermochemical properties, bond energies, and internal rotation potentials of acetic acid hydrazide (CH3CONHNH2), acetamide (CH3CONH2), and N-methyl acetamide (CH3CONHCH3), and their radicals corresponding to the loss of hydrogen atom, have been studied. Gas-phase standard enthalpies of formation and bond energies were calculated using the DFT methods B3LYP/6-31G(d,p), B3LYP/6-31G(2d,2p) and the composite CBS-QB3 methods employing a series of work reactions further to improve the accuracy of the ΔHf°(298 K). Molecular structures, vibration frequencies, and internal rotor potentials were calculated at the DFT level. The parent molecules’ standard formation enthalpies of CH3–C=ONHNH2, CH3–C=ONH2, and CH3–C=ONHCH3 were evaluated as −27.08, −57.40, and −56.48 kcal mol−1, respectively, from the CBS–QB3 calculations. Structures, internal rotor potentials, and C–H and N–H bond dissociation energies are reported. The DFT and the CBS-QB3 enthalpy values show close agreement, and this accord is attributed to the use of isodesmic work reactions for the analysis. The agreement also suggests this combination of the B3LYP/work reaction approach is acceptable for larger molecules. Internal rotor potentials for the amides are high, ranging from 16 to 22 kcal mol−1.

Synthesis, Characterization and In-Silico Analysis of New 2-Pyrazolines

Heterocyclic compounds such as pyrazolines, pyrimidines, oxazole and isoxazole exhibit different pharmacological activities. The current study involves synthesis of new 2-pyrazolines. The synthesis involves the cyclocondensation reaction of substituted chalcones with (4-fluorophenylthio)acetic acid hydrazide (FTAH) under reflux. The chalcones (C1-C7 / 1a-1g) were synthesized from the reaction of substituted acetophenone with substituted benzaldehyde and FTAH was prepared from 4-fluro thiophenol. New 2-pyrazolines were obtained in good yields (60-70 %). All the compounds were characterized by FT-IR, 1H, 13C NMR and mass spectra. PASS analysis was carried out for the 2-pyrazolines synthesized (P1-P7 / 3a-3g).

Synthesis of some new 4-(2,4-dimethyl-phenyl)-2H-phthalazinone derivatives

Aroylation of m-xylene by phthalic anhydride under Friedel craft’s reaction conditions to afford the corresponding o-aroylbenzoic acid derivative 2, which followed by cyclization reaction with hydroxylamine hydrochloride to produce the correlating benzoxazinone derivative 3, which was utilized as a precursor for the formation of some novel phthalazinone derivatives 4 ˗ 6. This transformation was achieved by interactions with thiosemicarbazide, thiocarbohydrazide, and hydrazine monohydrate and/or ammonium acetate under suitable conditions. 4-Substituted-1(2H)- phthalazinone derivative 6, which undergoes N-alkylation using ethyl bromoacetate to produce the phthalazinone acetic acid ethyl ester derivative 7, that followed by the interaction with hydrazine monohydrate to afford the phthalazinone acetic acid hydrazide derivative 8. The latter product was conducted with different aromatic acid compounds in presence of POCl3, to give the correlating oxadiazoles 9, 10. The chemical structures of all the synthesized compounds are confirmed using physical and spectral data analyses like FT- IR, 1H-NMR, and mass spectroscopy.

Neuropharmacological Analysis of the Antidepressant Action of 2-[3-Methyl-7-(Thietan-3-Yl)-1-Ethylxanth-8-YLTHIO] Acetic Acid Hydrazide

A compound with low toxicity and pronounced antidepressant activity upon single and long-term administration was discovered by us earlier among a series of new thietanylxanthine derivatives. The present article focused on the central mechanisms of action of 2-[3-methyl-7-(thietan-3-yl)-1-ethylxanth-7-ylthio]acetic acid hydrazide (laboratory code M-20). Neuropharmacological analysis showed that M-20 at doses of 0.97 and 12 mg/kg exhibited effects indicative of possible stimulatory action on adrenergic and inhibitory action on GABA-ergic neurotransmission in brains of outbred white mice. M-20 at a dose of 12 mg/kg produced an activating effect on the serotoninergic system in addition to action on the adrenergic and GABA-ergic systems and altered the activity of the cholinergic system. M-20 at doses of 0.97 and 12 mg/kg did not alter the effects of haloperidol and L-DOPA, which indicated that it did not influence dopaminergic neurotransmission and MAO-inhibiting activity. The results indicated that M-20 was promising (at the low dose) for use with depression associated with decreased activity of the serotoninergic system without side effects on the dopaminergic and cholinergic systems.

Structural, spectroscopic and computational investigations on (4,6-dimethyl-benzofuran-3-yl)-acetic acid hydrazide

The present work investigates structural and spectroscopic characteristics of (4,6-dimethyl-benzofuran-3-yl)-acetic acid hydrazide (4DBAH) through different spectroscopic methods (Infrared, Raman, and NMR) and quantum chemical computations. The quantum chemical computations are done with adequate level of theory using B3LYP from density functional with 6–311++G(d,p) basis set. Conformational analysis is performed to identify the structure corresponding to local minima and local maxima from the potential energy surface (PES).The theoretically simulated and Raman wavenumbers are compared with experimental data. The complete wavenumber assignments are accomplished by the potential energy distribution (PED) of individual vibrational modes. The experimental 1H and 13C NMR chemical shifts are investigated and then compared with computed NMR data. The AIM and NCI analysis gives more insights into the nature of different types of interactions, both attractive and repulsive nature present in the molecule. In addition, several analyses such as NBO, NLO, FMO, MEP and thermodynamic properties have also been conducted to determine the nature of the 4DBAH.

Synthesis and anxiolytic activity of 3-aryl-1-(41methoxyphenyl)-1-(6,7,8,9-tetrahydro5H -[1,2,4] triazolo[4,3-a]azepine-3-yl-methyl)- urea derivatives

Anxiety disorders are a widespread and growing problem of healthcare across the world. According to WHO data, neurosis and psychopaties are observed in 5–15 % of world population. In developed countries, about 20 % of population take anxiolytics permanently, and 30 % periodically. According to the WHO data it should be noted, that those pathologies affect different segments of population, from pediatric to geriatric population. Therapy of such nosologies imposes great loses on both individuals and society. 3-(41-Methoxyphenyl)-(6,7,8,9-tetrahydro-5H-[1,2,4]triazolo[4,3-a]azepine-3-yl-methyl)-аmine was obtained by condensation of 2-methoxy-3,4,5,6-tetrahydro-7H-azepine with (4-methoxyphenylamino) acetic acid hydrazide and further cyclization of the intermediate product. 3-Aryl-1-(41-methoxyphenyl)1-(6,7,8,9-tetrahydro-5H-[1,2,4]triazolo[4,3-a]azepine-3-yl-methyl)-urea derivatives were obtained by condensation of 3-(41-methoxyphenyl)-(6,7,8,9-tetrahydro-5H-[1,2,4]triazolo[4,3-a]azepine-3-ylmethyl)-аmi ne with appropriate arylisocyanates in dry benzene medium. The aim of the study – to synthesize and study an anxiolytic activity of 3-aryl-1-(41-methoxyphenyl)1-(6,7,8,9-tetrahydro-5H-[1,2,4]triazolo[4,3-a]azepine-3-yl-methyl)-urea derivatives in comparison with known drugs diazepam and gidazepam on the stage of primary pharmacological screening. Tranquilizing activity of compounds was evaluated on models of «open field», «corazol convulsions» and «wire test» on mice, after administration at doses, equimolar to ED50 of diazepam. Diazepam (2 mg/kg) and gidazepam (2 mg/kg) were used as referent compounds. There were established, that 3-aryl-1-(41-methoxyphenyl)-1-(6,7,8,9-tetrahydro-5H-[1,2,4]triazolo[4,3-a]azepine-3-yl-methyl)-urea derivatives are characterized by anticonvulsant and anxiolytic activity. The absence of muscle relaxant effect and absence or moderate inhibition of horizontal activity, suggest the absence of GABAergic component in specific activity of studied compounds. Anticonvulsant and behavioral activity («open field») of studied compounds depend on modification of substitutes on para- and ortho- positions of benzene ring of N`-group of urea. By specific activity, researched compounds are not inferior (or exceed) daytime tranquilizer gidazepam. On open field model compound 1-(41-methoxyphenyl)-1-(6,7,8,9-tetrahydro-5H-[1,2,4]triazolo[4,3-a] azepin-3-yl-methyl)-3-(p-tolyl)-urea 5 d is characterized by lesser influence on horizontal, vertical and exploration activity, while grooming and quantity of feces droppings are significantly inhibited. This indicates less sedation in comparison to such of diazepam. However, on open field model compound 5 d exceeds daytime tranquilizer gidazepam by results of primary screening.

Нейрофармакологический анализ антидепрессивного действия гидразида 2-[3-метил-7-(тиетанил-3)-1-этилксантинил-8-тио]уксусной кислоты

Ранее нами в ряду новых производных тиетанилксантина было обнаружено соединение, обладающее низкой токсичностью и выраженной антидепрессивной активностью при однократном и длительном введении. Данная статья посвящена изучению центральных механизмов действия гидразида 2-[3-метил-7-(тиетанил-3)-1-этилксантинил-8-тио]уксусной кислоты (лабораторный шифр М-20). По результатам нейрофармакологического анализа было показано, что соединение М-20 в дозах 0,97 и 12 мг/кг проявляет эффекты, указывающие на возможное стимулирующее действие на адренергическую и угнетающее на ГАМК-ергическую нейропередачу в головном мозге белых беспородных мышей. В дозе 12 мг/кг соединение М-20, помимо взаимодействия с адренергической и ГАМК-ергической системами, оказывало активирующее действие на серотонинергическую и изменяло активность холинергической системы. Соединение М-20 в дозах 0,97 и 12 мг/кг не влияло на эффекты галоперидола и L-ДОФА, что свидетельствует об отсутствии у него действия на дофаминергическую нейропередачу, а также МАО-ингибирующей активности. Полученные результаты указывают на перспективность применения вещества М-20 при депрессиях, связанных с дефицитом активности серотонинергической системы, при отсутствии побочных эффектов со стороны дофаминергической и холинергической (в низкой дозе) систем.

Synthesis and Antimicrobial Activity of Novel Oxothiazolidine Derivatives

In this article, acid hydrazide 2, a functional group, was synthesized by the reaction of (4-chloro-12- methyl-16,17-dihydro-15-thia-6,11-diaza-cyclopenta[a]phenanthren-7-ylsulfanyl)acetic acid ethyl ester (1) with hydrazine yield (4-chloro-12-methyl-16,17-dihydro-15-thia-6,11-diazacyclopenta[a]- phenanthren-7-ylsulfanyl)acetic acid hydrazide (2) is discussed. The reactive acid hydrazide compound 2 was utilized for the synthesis of amides 3, Schiff’s bases 4 and thiazolidine 5 derivatives. The structures of target compounds were confirmed by elemental analysis and spectral data. The antimicrobial activity of new compounds were studied against Streptococcus sp., Bacillus megaterium, Staphylococcus aureus, Escherichia coli, Bacillus cereus, Bacillus subtilis, Proteus valgaris and Pseudomonas aeroginosa by the agar well diffusion method. Compounds 4b, 5a, 5b and 5c showed good antimicrobial activity

Antioxidant properties of some novel derivatives thiazolo[4,5-b] pyridine

The synthesis and determination of the antioxidant activity of some novel (5,7-dimethyl-2-oxo-thiazolo[4,5-b]pyridine-3-yl)-acetic acid hydrazide derivatives are described in this article. The transformation of the base heterocycle was carried out via the reactions of acylation, [2+3]cyclocondensation, Knoevenagel condencation and alkylation for the purpose to obtain substances with a satisfactory pharmacological profile. Antioxidant activity of the synthesized compounds was evaluatedin vitroby means of the scavenging metod effect on 2,2 diphenyl-1-picrylhydrazyl (DPPH) radicals.

Synthesis and Structure of Hybrid Compounds Based on Phosphoryl Acetic Acid Hydrazide, Isatin, and Sterically Hindered Phenols

In order to obtain novel biologically active substances with various types of activity, hybrid compounds based on 2-(diphenylphosphoryl)acetohydrazide, isatin, and sterically hindered phenols are synthesized. Their molecular and crystal structures are determined by X-ray crystallography.