Alcoholic Sodium Hydroxide Research Articles

Spectroscopic evidence and mechanistic insights on dehydrofluorination of PVDF in alkaline medium

This study presents newer insights on the dehydrofluorination of poly(vinylidene fluoride), PVDF, in alcoholic sodium hydroxide using infrared (IR), Raman and nuclear magnetic resonance (1H and 1H {19F}) spectroscopies. Details on the reactivity of phases and site selectivity of different orientations viz head-to-tail and tail-to-tail is comprehensively examined using IR/Raman and NMR (1D and 2D), respectively. The α-phase is prominently involved in dehydrofluorination and transforms into the more electroactive β-phase. 1H NMR spectra highlight that the tail-to-tail addition of PVDF is not disturbed and remains unaffected during dehydrofluorination reaction. Furthermore, 1H-19F heteronuclear correlation spectroscopy (Hetero COSY) clearly evidences the formation of the –(CH=CF)– double bond in dehydrofluorinated PVDF. Moreover, detailed mechanistic insights of dehydrofluorination reaction and possible internal crosslinking during the chemical transformation is presented.

Synthesis, Characterization and Antimicrobial Activity of Isoxazoline Derivatives

In present study isoxazoline derivatives were synthesized and antimicrobial activity of different derivatives were checked with various microbial stain. Various intermediates was synthesized and characterized in between time to time by chromatography using TLC. An isoxazoline series of compounds were synthesized by condensation reaction of phenyl ethyl acetate with substituted benzaldehyde in presence of alcoholic sodium hydroxide to get intermediate phenethyl cinnamate (chalcones), which were further treated with hydroxylamine hydrochloride in presence of sodium hydroxide to get isoxazoline derivatives. The synthesized compounds were characterized on the basis of their spectral (IR) data and evaluated for the antimicrobial activity by using Zone of Inhibition by cup plate method.

Synthesis and Antibacterial Activity of 3-(3-methoxyphenyl)-2-methylsulfanyl-3Hquinazolin-4-one (4) and 3-(3-methoxyphenyl)-2-thioxo-2,3-dihydro1H-quinazolin-4-one (3) Via N-(3- methoxyphenyl)-methyl dithiocarbamic acid (2)

Introduction: Heterocyclic compounds have already provided a platform for the rapid swap of research in the areas of organic, pharmaceutical, analytical, and medicinal chemistry. In the pharmaceutical industry, among the top two hundred branded drugs, more than 75% have heterocyclic fragments in their structures. Methods/Experimental: The compound, 3-(3-methoxyphenyl)-2-thioxo-2,3-dihydro1H-quinazolin-4-one (3) was synthesized by dissolving Methyl anthranilate and N-(3- methoxyphenyl)-methyl dithiocarbamic acid in ethanol and anhydrous potassium carbonate and refluxed for 23 h and re-precipitated by treating with dilute hydrochloric. The 3-(3-methoxyphenyl)-2-thioxo-2,3-dihydro-1Hquinazolin-4-one was dissolved in 40 mL of 2% alcoholic sodium hydroxide solution and dimethyl sulphate was added drop wise with stirring for 1 h, the reaction mixture was then poured into ice water to get 3-(3-methoxyphenyl)-2-methylsulfanyl-3Hquinazolin-4-one (4). The synthesized compounds were screened against various strains of microorganism; Staphylococcus aureus, Bacillus species, Escherichia coli, Klebsiella pneumonia, Enterococcus Feacalis, Pseudomonas aeriginosa, and candida albicans. Compounds 3 and 4 showed significant activity against Staphylococcus aureus, Bacillus species, Escherichia coli, Klebsiella pneumonia, Enterococcus Feacalis, Pseudomonas aeriginosa, and candida albicans, MIC ranging from 6 – 12 mg/mL. Result: The compounds exhibited significant antibacterial activity in comparison to control. Conclusions: From our findings, the compounds synthesized have higher antibacterial activities as compared to the standard antibacterial drug.

SYNTHESIS AND PROPERTIES OF CARBOXYMETHYL CELLULOSE FROM AGRICULTURAL WASTE – SUGARCANE LEAVES

"Sugarcane leaves are an abundant agricultural waste with the potential for use as a source of cellulose. Cellulose from sugarcane leaves was converted to carboxymethyl cellulose (CMC) by carboxymethylation using sodium hydroxide and monochloroacetic acid in isopropyl alcohol. The yield of CMC was 212.16%. A degree of substitution (DS) equivalent to 0.79 was obtained during the conversion, indicating that the product was water-soluble. Fourier transform infrared (FT-IR) spectroscopy confirmed the presence of major peaks expected for carboxymethyl substitution, compared to commercial CMC. Thermal properties were studied using simultaneous thermal analysis (STA). Melting temperature (Tm) and degradation temperature (Td) of the sample were 116.6 °C and 270.4 °C, respectively, while the residual mass of 36.49% at 800 °C indicated the presence of a non-volatile component fraction. CMC morphology showed a non-circular form with small particles. Results indicated the potential of sugarcane leaves for production of commercial grade CMC."

Synthesis of Pyrano, Pyrido, Oxazino, and Spiro Pyrazole Derivatives and Their Antimicrobial Activity

Condensation of 5-methyl-2-phenyl-1,2-dihydro-3H-pyrazol-3-one with 4-hydroxybenzaldhyde in alcoholic sodium hydroxide yielded 4-(4-hydroxybenzylidene)-5-methyl-2-phenyl-2,4-dihydro-3H-pyrazol-3-one, and treatment of the latter with acetylacetone, hydrazine hydrate, ethyl cyanoacetate, and ethyl acetoacetate gave pyranopyrazole, pyrazolopyrazole, and pyrazolopyridine derivatives. 5-Methyl-2-phenyl-1,2-dihydro-3H-pyrazol-3-one was reacted with 2,4-dichlorobenzoyl isothiocyanate, thiosemicarbazide, and hydrazine hydrate to afford pyrazolooxazine, pyrazolopyrazole, and spiro[pyrazole-3,3′-pyrazolo[3,4-c]pyrazole] derivatives. Some of the newly synthesized compounds showed high antimicrobial activity against three microbial strains (S. aureus, E. coli, C. albicans).

Fast improved polyol method for synthesis of Pd/C catalyst with high performance toward ethanol electrooxidation

Highly dispersed palladium nanoparticles that are successfully decorated on the charcoal activated carbon by a rapid and simple improved polyol method in Ethylene Glycol (EG) media in the presence of ethanolic sodium hydroxide, without any protection by capping agent, is proposed for the first time in this paper. Along this process, H2PdCl4 in ethylene glycol media can be reduced to metallic palladium at 40°C in the presence of alcoholic sodium hydroxide. Therefore, it can be claimed that ethanolic sodium hydroxide is behaving like a mild reducing agent in the EG media. Pd/C catalysts are also synthesized using improved and traditional methods for comparison. Catalysts synthesized in two different ways were characterized by Transmission Electron Microscopy (TEM), X-Ray Diffraction (XRD), and Inductively Coupled Plasma Mass Spectrometry (ICP-MS). The results illustrated that Pd/C synthesized using the improved polyol method had better dispersity and its diameter was equal to 8–10 nm which was lower compared to the conventional polyol method. The electrocatalytic performance of both Pd/C catalysts synthesized by two methods was investigated by cyclic voltammetry and chronoamperometry in the solution of 1.0 M EtOH +1.0 M NaOH at room temperature. The results showed that the Pd/C catalyst synthesized by the improved method had a significantly enhanced the activity and durability for Ethanol Oxidation Reaction (EOR) that can be related to the good dispersity of Palladium nanoparticles over support due to the improved polyol method.

Design and Synthesis of Fused and Spiro Pyrazole Derivatives

Condensation of 5-methyl-2-phenyl-1,2-dihydro-3H-pyrazol-3-one with p-hydroxybenzaldehyde in alcoholic sodium hydroxide yielded (Z)-4-(4-hydroxybenzylidene)-5-methyl-2-phenyl-2,4-dihydro-3H-pyrazol-3-one which was treated with acetylacetone, hydrazine hydrate, ethyl cyanoacetate, and ethyl acetoacetate to afford pyranopyrazole, pyrazolopyrazole, pyrazolopyridine, and 6-aminopyrazolopyridine derivatives, respectively. 5-Methyl-2-phenyl-1,2-dihydro-3H-pyrazol-3-one was also reacted at the enamino carbon atom with 2,4-dichlorobenzoyl isothiocyanate, thiosemicarbazide, and hydrazine hydrate to produce pyrazolooxazine, pyrazolopyrazole, and spiro[pyrazole-3,3′-pyrazolo[3,4-c]pyrazole] derivatives.

Synthesis and Some Chemical Transformations of Unsaturated Ketones of the Dihydropyran Series

Methods have been developed for the synthesis of unsaturated ketones of the dihydropyran series via aldolization-crotonization of 3,4-dihydro-2H-pyran-2-carbaldehyde with some unsaturated ketones. Among the proposed methods, the optimal were reactions carried out in 20% alcoholic sodium hydroxide at room temperature, which ensured higher selectivity, high yield (85-95%) of the target products, and minimization of side processes. The obtained unsaturated ketones were subjected to various chemical transformations involving the side-chain double bond, and their new derivatives were synthesized. In particular, the oxidation of unsaturated ketones with 28% hydrogen peroxide gave the corresponding epoxy ketones which reacted with secondary amines to afford amino alcohols.

Synthesis and characterization of some novel aryl and heteroaryl chalcone derivatives of 3-(3,4,5-trimethoxyphenyl)-1-phenyl-1H-pyrazole-4-carbaldehyde for assessing their potentials as anticancer agents

In the present study, a novel series of nine derivatives of 1-phenyl-3-(3,4,5-trimethoxyphenyl)-1H-pyrazole substituted chalcones 6a–6i were synthesized with an aim to assess their anticancer activities. The chalcone derivatives were synthesized by the Claisen condensation of 1-phenyl-3-(3,4,5-trimethoxyphenyl)-1H-pyrazole-4-carbaldehyde 4 with various aryl and heteroaryl acetophenones 5a–5i by treatment with alcoholic sodium hydroxide in methanol at reflux temperature in good to excellent yields. The newly synthesized derivatives were well characterized by IR, NMR, and HRMS spectroscopic techniques. The title compounds were evaluated for in vitro antibacterial activity against a panel of gram-positive and gram-negative bacteria and screened for anticancer activity employing EGFR lung protein based on in silico molecular docking studies. The study results showed IC50 value ranging between 39–94 μg/mL compared to the standard Camptothecin with an IC50 value of 47 μg/mL which indicates the anticancer potential of the majority of the synthesized compounds.

A regioselective and convenient one-pot multicomponent synthesis of 9-amino-3,5-diaryl-4,9-dihydro-5H-[1,2,4]triazolo[5,1-c][1,2,4]triazepine-8-thiol

ABSTRACTAn efficient and environment-friendly procedure for the synthesis of a new series of nitrogen bridge-head [1,2,4]triazolo[5,1-c][1,2,4]triazepine derivatives through one-pot three-component reaction of polyfunctional triazole with aromatic aldehydes and acetophenone derivatives using alcoholic sodium hydroxide solution. The same new products were prepared in classical route through reaction of triazole with the corresponding chalcones under the same conditions.

Valorization of lignin and cellulose in acid-steam-exploded corn stover by a moderate alkaline ethanol post-treatment based on an integrated biorefinery concept.

BackgroundDue to the unsustainable consumption of fossil resources, great efforts have been made to convert lignocellulose into bioethanol and commodity organic compounds through biological methods. The conversion of cellulose is impeded by the compactness of plant cell wall matrix and crystalline structure of the native cellulose. Therefore, appropriate pretreatment and even post-treatment are indispensable to overcome this problem. Additionally, an adequate utilization of coproduct lignin will be important for improving the economic viability of modern biorefinery industries.ResultsThe effectiveness of moderate alkaline ethanol post-treatment on the bioconversion efficiency of cellulose in the acid-steam-exploded corn stover was investigated in this study. Results showed that an increase of the alcoholic sodium hydroxide (NaOH) concentration from 0.05 to 4% led to a decrease in the lignin content in the post-treated samples from 32.8 to 10.7%, while the cellulose digestibility consequently increased. The cellulose conversion of the 4% alcoholic NaOH integrally treated corn stover reached up to 99.3% after 72 h, which was significantly higher than that of the acid steam exploded corn stover without post-treatment (57.3%). In addition to the decrease in lignin content, an expansion of cellulose I lattice induced by the 4% alcoholic NaOH post-treatment played a significant role in promoting the enzymatic hydrolysis of corn stover. More importantly, the lignin fraction (AL) released during the 4% alcoholic NaOH post-treatment and the lignin-rich residue (EHR) remained after the enzymatic hydrolysis of the 4% alcoholic NaOH post-treated acid-steam-exploded corn stover were employed to synthesize lignin-phenol-formaldehyde (LPF) resins. The plywoods prepared with the resins exhibit satisfactory performances.ConclusionsAn alkaline ethanol system with an appropriate NaOH concentration could improve the removal of lignin and modification of the crystalline structure of cellulose in acid-steam-exploded corn stover, and consequently significantly improve the conversion of cellulose through enzymatic hydrolysis for biofuel production. The lignin fractions obtained as byproducts could be applied in high performance LPF resin preparation. The proposed model for the integral valorization of corn stover in this study is worth of popularization.

Synthesis and Anti-microbial Activity of Novel Isoxazoline Mannich base Derivatives containing Carbazole Ring

A Novel Series of Compounds were synthesized by Condensation reaction of Carbazole aldehyde with Substituted Acetophenone derivatives 4 (a-d) in presence of alcoholic Sodium hydroxide Solution to get Chalcone Intermediates 5 (a-d), which were further treated hydroxyl amine hydrochloride in presence of Pyridine to get Iso Oxazoline Derivatives 6 (a-d). The latter were refluxed with Substituted Primary amines and formaldehyde for 8–10 hrs to get Mannich bases. The Structures of new compounds were confirmed by IR and 1H NMR and 13C NMR Spectral Data. Anti-bacterial and Anti-fungal Activities were evaluated and compared with the standard drugs, some compounds of the series Exhibited Promising Anti-microbial and Anti-fungal Activity Compared to Standard Drugs.

Design, Synthesis, Docking Study & Antibacterial Evaluation of 1,3- Diarylpyrazolyl Substituted Indolin-2-ones

In the present investigation, a series ofnovel 3-((1,3-diphenyl-1H-pyrazol-4-yl)methylene)indolin-2-one was synthesized by the Claisen-Schmidt condensation of indolin-2-one with substituted diaryl formylpyrazoles using alcoholic sodium hydroxide. The chemical structures of the newly synthesized compounds were characterized by IR, 1HNMR, and mass spectroscopy. The title compounds were evaluated for qualitative (zone of inhibition) and quantitative antibacterial activity (MIC) by agar diffusion and broth microdilution MIC (minimum inhibitory concentration) methods, respectively against Staphylococcus aureus, Bacillus subtilis, Escherichia coli, and Klebsiella pneumoniae. All the synthesized compounds were found active against Gram-positive bacteria, while showed very weak activity against Gram-negative bacteria. Docking study was performed to check interaction of synthesized compounds with the target DNA gyrase.

Palladium-catalyzed transfer hydrogenation of nitrobenzenes: investigation of the selectivity

Aromatic nitro compounds can be reduced via transfer hydrogenation in the presence of Pd on basic supports in alcoholic sodium hydroxide yielding not only the appropriate amine, but the azobenzene and azoxybenzene intermediates as well. Depending on the support, the reaction time and the amount of sodium hydroxide added, both the intermediates and the amine can be produced with excellent selectivity.

Synthesis and Biological Evaluation of Mannich Bases of Isoxazoline Derivatives as Novel Anti‐Microbial Agents

A novel series of compounds were synthesized by condensation reaction of substituted acetophenone (1a-b) with substituted aldehyde (2a-b) in presence of alcoholic sodium hydroxide to get intermediate chalcones (3a-c), which were further treated with hydroxylamine hydrochloride in presence of sodium hydroxide to get isoxazolines derivatives (4a-c). The latter were refluxed with substituted primary amines and formaldehyde for 6‐10 h to afford Mannich bases. The synthesized compounds were characterized on the basis of their spectral (IR, 1HNMR) data and evaluated for the antimicrobial activity by using Zone of Inhibition by cup plate method and Minimum Inhibitory Concentration by broth dilution method.

Novel nucleophilic rearrangement of 1-substituted isoquinolines using an alcoholic sodium hydroxide solution

The reactions of 1-substituted isoquinolinium salts have been studied in the cases of the 1-isopropyl-2-methyl- and 2-methyl-1-cyclohexylisoquinolinium iodides using an alcoholic solution of sodium hydroxide. The possibility of preparing a wide range of spirocyclic ketones, alcohols, amino alcohols, and isochroman-3-ones has been demonstrated.

Unusual recyclization of 2-methyl-1-phenyliso- quinolinium iodide to 1-phenyl-1,4-dihydro- 3h-isochroman-3-one

The formation of an isochroman-3-one was unexpectedly observed during the course of studying the rearrangement of 1-substituted isoquinolinium salts in the presence of O-nucleophiles. Hence refluxing 2-methyl-1-phenylisoquinolinium iodide (1) with a solution of sodium hydroxide in alcohol and subsequent treatment with acid gave a high yield of the 1-phenyl-1,4-dihydro-3H-isochroman-3-one (2). It was found that compound 2 is only formed after the acidification of the reaction mixture at the separation stage.

Synthesis and Antimicrobial Activity of Some 3‐(5‐Phenyl‐4,5‐dihydro‐1‐substitutedpyrazol‐3‐yl) chromen‐2‐one

The title compounds were synthesized by condensation of 3‐acetyl chromen‐2‐one with benzaldehyde in presence of alcoholic sodium hydroxide to get intermediate 3‐(3‐phenyl acryloyl) chromen‐2‐one, which were further treated with hydrazine hydrate to get 3‐(5‐phenyl‐4,5‐dihydro‐1H‐pyrazol‐3‐yl) chromen‐2‐one. The latter were refluxed with various amino compounds and various aldehyde derivatives on water bath for 5 h to afford title compounds. All the compounds were tested for their antibacterial and antifungal activities by the cup plate method.

Determination of total cholesterol in serum by isotope dilution liquid chromatography tandem mass spectrometry

目的 建立同位素稀释液相色谱串联质谱(LC/MS/MS)测定血清总胆固醇的方法.方法 血清样品中加入[3,4-13C2]-胆固醇作内标,用氢氧化钠水解血清胆固醇酯为胆固醇,用三氧化铬-硫酸氧化胆固醇为胆甾-4-烯-3,6-二酮,用LC/MS/MS分析胆固醇氧化产物,采用大气压化学电离源,用多反应监测(MRM)模式和选择离子监测(SIR)模式检测,用修正标准曲线法对血清样品进行定量.结果 两种检测模式的峰面积比与胆固醇浓度的线性相关系数均大于0.999 9.MRM模式测定血清总胆固醇的平均批内变异系数(CV)为0.95%(范围0.92%～0.99%),平均总CV为0.86%(0.82%～0.89%);SIR模式平均批内CV为0.64%(0.54%～0.77%),平均总CV为0.69%(0.62%～0.81%).测定国际或国家标准物质结果与靶值的平均偏差在MRM模式下为0.23%(0.14%～1.00%),SIR模式为0.24%(0.07%～1.27%).结论 成功建立了LC/MS/MS测定血清总胆固醇的方法,方法特异、精密、简便,可望用作血清胆固醇测定的参考方法。

Measurement of serum total glycerides and free glycerol by high-performance liquid chromatography

Serum levels of total glycerides and free glycerol are important indices of lipid metabolism and cardiovascular disease risk. Convenient enzymatic methods of measurement have been available, but they are susceptible to interference. Situations exist in both research and clinical laboratories in which more specific and precise methods are needed. We developed HPLC methods for the measurement of serum total glycerides and free glycerol. For total glycerides, serum was mixed with an internal standard (1,2,4-butanetriol) and treated with alcoholic sodium hydroxide to hydrolyze glycerides to glycerol. After deproteinization with tungstic acid, the glycerol was benzoylated with an optimized Schotten-Baumann reaction and analyzed by HPLC. For free glycerol, serum was equilibrated with the internal standard and deproteinized with tungstic acid to remove the glycerides. The glycerol was benzoylated and analyzed as for total glycerol. Various factors were investigated, and no significant sources of interference were detected. The total coefficients of variation ranged from 0.7% to 2.0% for total glycerides and from 1.7% to 3.2% for free glycerol. The analytical recoveries ranged from 98.5% to 101.6%. In conclusion, simple and reliable HPLC methods for serum total glycerides and free glycerol have been developed. The methods may also be used for the analyses of glycerol or glycerides in other biological samples.