Phenol urea-melamine formaldehyde (PUMF) resin adhesive was prepared by using phenol, urea and melamine in two different molar ratios. The effects of the molar ratio of formaldehyde, phenol, urea, melamine on performance of PUMF resin adhesive were studied. The resin developed was characterized by differential scanning calorimeter (DSC) and Fourier transform infrared spectroscopy (FTIR). Plywood was manufactured using the developed resin and bonding properties were evaluated as per IS: 848-2006. The results indicated that the plywood made using PUMF resin of the molar ratio (phenol: urea: melamine): Formaldehyde 1:0.79:0.38:2.15 at pH 9.0 yield best result. The studies indicate that the PUMF can be used make wood-based panels of boiling water resistant grade.
{"title":"Synthesis of PUMF Resin for the Manufacture of Plywood","authors":"B. Mamatha, D. Sujatha, D. Uday","doi":"10.7598/cst2019.1534","DOIUrl":"https://doi.org/10.7598/cst2019.1534","url":null,"abstract":"Phenol urea-melamine formaldehyde (PUMF) resin adhesive was prepared by using phenol, urea and melamine in two different molar ratios. The effects of the molar ratio of formaldehyde, phenol, urea, melamine on performance of PUMF resin adhesive were studied. The resin developed was characterized by differential scanning calorimeter (DSC) and Fourier transform infrared spectroscopy (FTIR). Plywood was manufactured using the developed resin and bonding properties were evaluated as per IS: 848-2006. The results indicated that the plywood made using PUMF resin of the molar ratio (phenol: urea: melamine): Formaldehyde 1:0.79:0.38:2.15 at pH 9.0 yield best result. The studies indicate that the PUMF can be used make wood-based panels of boiling water resistant grade.","PeriodicalId":10087,"journal":{"name":"Chemical science transactions","volume":"10 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2018-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75549298","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Rahul Shah, Amanullakhan Pathan, Hiral M Vaghela, S. Ameta, K. Parmar
Synthesis of copper nanoparticles using zingiber officinale, piper nigrum and piper longum extract has been studied. The synthesized copper nanoparticles were characterized using UV-Visible spectroscopy, Fourier transform infrared spectroscopy (FTIR), x-ray diffraction (XRD), field emission gun scanning electron microscopy (FEG-SEM) with EDS and high resolution transmission electron microscopy (HR-TEM). The antibacterial activity of copper nanoparticles was studied against micro organisms like against Bacillus subtilis (MTCC 441), Staphylococcus aureus (MTCC 737), Pseudomonas aeruginosa (MTCC 1681) and Escherichia coli (MTCC 1687). Keyword: Green synthesis, Copper nanoparticles, UV-Visible, FTIR, SEM, TEM, XRD
研究了用生姜、胡椒和胡椒提取物合成纳米铜的方法。采用紫外可见光谱、傅里叶变换红外光谱(FTIR)、x射线衍射(XRD)、场发射枪扫描电镜(fg - sem)、能谱仪(EDS)和高分辨率透射电镜(HR-TEM)对合成的铜纳米颗粒进行了表征。研究了铜纳米颗粒对枯草芽孢杆菌(MTCC 441)、金黄色葡萄球菌(MTCC 737)、铜绿假单胞菌(MTCC 1681)和大肠杆菌(MTCC 1687)等微生物的抑菌活性。关键词:绿色合成，铜纳米颗粒，紫外可见，FTIR, SEM, TEM, XRD
{"title":"Green Synthesis and Characterization of Copper Nanoparticles Using Mixture (Zingiber officinale, Piper nigrum and Piper longum) Extract and its Antimicrobial Activity","authors":"Rahul Shah, Amanullakhan Pathan, Hiral M Vaghela, S. Ameta, K. Parmar","doi":"10.7598/cst2019.1517","DOIUrl":"https://doi.org/10.7598/cst2019.1517","url":null,"abstract":"Synthesis of copper nanoparticles using zingiber officinale, piper nigrum and piper longum extract has been studied. The synthesized copper nanoparticles were characterized using UV-Visible spectroscopy, Fourier transform infrared spectroscopy (FTIR), x-ray diffraction (XRD), field emission gun scanning electron microscopy (FEG-SEM) with EDS and high resolution transmission electron microscopy (HR-TEM). The antibacterial activity of copper nanoparticles was studied against micro organisms like against Bacillus subtilis (MTCC 441), Staphylococcus aureus (MTCC 737), Pseudomonas aeruginosa (MTCC 1681) and Escherichia coli (MTCC 1687). Keyword: Green synthesis, Copper nanoparticles, UV-Visible, FTIR, SEM, TEM, XRD","PeriodicalId":10087,"journal":{"name":"Chemical science transactions","volume":"26 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2018-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89149164","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Bereket Mochona, Elizabeth Mazzio, Madhavei Gangapurum, Nelly Mateeva, K K Redda
In an effort to establish new benzimidazole related structural leads with improved anticancer activity, several new benzimidazole derivatives (5a-i) with 1,3,4-oxadiazole scaffold incorporated were synthesized and studied for their anticancer activity. The anticancer screening against MDA-MB-231 breast cancer cell lines showed that compound (5c) exhibited moderate cytotoxicity.
{"title":"Synthesis of Some Benzimidazole Derivatives Bearing 1,3,4-Oxadiazole Moiety as Anticancer Agents.","authors":"Bereket Mochona, Elizabeth Mazzio, Madhavei Gangapurum, Nelly Mateeva, K K Redda","doi":"10.7598/cst2015.1029","DOIUrl":"https://doi.org/10.7598/cst2015.1029","url":null,"abstract":"<p><p>In an effort to establish new benzimidazole related structural leads with improved anticancer activity, several new benzimidazole derivatives (<b>5a-i</b>) with 1,3,4-oxadiazole scaffold incorporated were synthesized and studied for their anticancer activity. The anticancer screening against MDA-MB-231 breast cancer cell lines showed that compound (<b>5c</b>) exhibited moderate cytotoxicity.</p>","PeriodicalId":10087,"journal":{"name":"Chemical science transactions","volume":"4 2","pages":"534-540"},"PeriodicalIF":0.0,"publicationDate":"2015-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4594831/pdf/nihms702132.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"34242988","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
A. Kumar, S. Kanakaraju, B. Prasanna, G. Chandramouli
The Baylis-Hillman adducts 3(a-e) and 6(a-g) were prepared by the reaction of appropriate aldehydes with alkenes in presence of catalytic amount of urotropine with ionic liquids under microwave irradiation. Structures of the newly synthesized compounds were characterized by spectral studies. The antibacterial studies of Baylis-Hilmann compounds for analysis of the structural requirements for antibacterial activity using VLife MDS 3.5 has been carried out.
{"title":"Synthesis, Molecular Docking Studies and Antibacterial Evaluation of Baylis-Hillman Adducts of Coumarin and Pyran Derivatives Using Ionic Liquid under Microwave Irradiation","authors":"A. Kumar, S. Kanakaraju, B. Prasanna, G. Chandramouli","doi":"10.7598/CST2013.415","DOIUrl":"https://doi.org/10.7598/CST2013.415","url":null,"abstract":"The Baylis-Hillman adducts 3(a-e) and 6(a-g) were prepared by the reaction of appropriate aldehydes with alkenes in presence of catalytic amount of urotropine with ionic liquids under microwave irradiation. Structures of the newly synthesized compounds were characterized by spectral studies. The antibacterial studies of Baylis-Hilmann compounds for analysis of the structural requirements for antibacterial activity using VLife MDS 3.5 has been carried out.","PeriodicalId":10087,"journal":{"name":"Chemical science transactions","volume":"46 1","pages":"561-569"},"PeriodicalIF":0.0,"publicationDate":"2013-04-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74154537","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
A rapid, efficient and green methodology has been developed for the synthesis of 3,3'-arylmethylene-bis-4-hydroxycoumarins by microwave assisted condensation of aromatic aldehydes and 4-hydroxycoumarin without use of any solvent, catalyst or solid surface.
{"title":"A Rapid, Efficient and Green Method for Synthesis of 3,3'-Arylmethylene-bis-4-hydroxycoumarins without Use of any Solvent, Catalyst or Solid Surface","authors":"A. Gupta, Swati Samanta, R. Mondal, A. Mallik","doi":"10.7598/CST2013.388","DOIUrl":"https://doi.org/10.7598/CST2013.388","url":null,"abstract":"A rapid, efficient and green methodology has been developed for the synthesis of 3,3'-arylmethylene-bis-4-hydroxycoumarins by microwave assisted condensation of aromatic aldehydes and 4-hydroxycoumarin without use of any solvent, catalyst or solid surface.","PeriodicalId":10087,"journal":{"name":"Chemical science transactions","volume":"9 1","pages":"524-528"},"PeriodicalIF":0.0,"publicationDate":"2013-04-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78628820","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
N. Korde, S. Gaikwad, B. Khade, A. Rajbhoj, B. Ambedkar
Hydroxyphenyl)-3-propane,1,3-diones 4(LA-LF) have been synthesized by a simple and convenient method employing Baker-Venkatraman transformation on corresponding 2- acetylphenyl benzoate by conventional as well as ultrasound irradiation method. The structure of synthesized compounds has been assigned on the basis of elemental and spectral analysis (IR, 1 H NMR, 13 C NMR, UV/Vis, Mass). The synthesized compounds were evaluated for antibacterial and antifungal activities. Utilization of ultrasound irradiation, simple reaction conditions, isolation and purification makes this manipulation very interesting from an economic and environmental perspective.
{"title":"Efficient Ultrasound Synthesis, Characterizations and Antimicrobial Screening of Novel Cyclic β-Diketones","authors":"N. Korde, S. Gaikwad, B. Khade, A. Rajbhoj, B. Ambedkar","doi":"10.7598/CST2013.355","DOIUrl":"https://doi.org/10.7598/CST2013.355","url":null,"abstract":"Hydroxyphenyl)-3-propane,1,3-diones 4(LA-LF) have been synthesized by a simple and convenient method employing Baker-Venkatraman transformation on corresponding 2- acetylphenyl benzoate by conventional as well as ultrasound irradiation method. The structure of synthesized compounds has been assigned on the basis of elemental and spectral analysis (IR, 1 H NMR, 13 C NMR, UV/Vis, Mass). The synthesized compounds were evaluated for antibacterial and antifungal activities. Utilization of ultrasound irradiation, simple reaction conditions, isolation and purification makes this manipulation very interesting from an economic and environmental perspective.","PeriodicalId":10087,"journal":{"name":"Chemical science transactions","volume":"21 1","pages":"407-412"},"PeriodicalIF":0.0,"publicationDate":"2013-04-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82217922","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The hydroboration of cyclopropane has been investigated using the B3LYP density functional method employing several split-valence basis sets. It is shown that the reaction proceeds via a four-centered transition state. Calculations at higher levels of theory were also performed at the geometries optimized at the B3LYP level, but only slight changes in the barriers were observed. Structural parameters for the transition state are also reported.
{"title":"Hydroboration of Cyclopropane: A Transition State Study","authors":"S. Singh, P. P. Thankachan","doi":"10.7598/CST2013.420","DOIUrl":"https://doi.org/10.7598/CST2013.420","url":null,"abstract":"The hydroboration of cyclopropane has been investigated using the B3LYP density functional method employing several split-valence basis sets. It is shown that the reaction proceeds via a four-centered transition state. Calculations at higher levels of theory were also performed at the geometries optimized at the B3LYP level, but only slight changes in the barriers were observed. Structural parameters for the transition state are also reported.","PeriodicalId":10087,"journal":{"name":"Chemical science transactions","volume":"41 5 1","pages":"479-484"},"PeriodicalIF":0.0,"publicationDate":"2013-04-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82764008","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
A. Allouch, I. Hassan, Adib Abou Dalle, H. El-Nakat, F. Omar
To be active, a heavy metal trap substrate must possess some degree of aqueous solubility. The use of cyclodextrins molecules, which can form inclusion complexes with the hydrophobic trap substrates, has provided the required solubility through the relatively hydrophobic cavity of native cyclodextrins and their derivatives that enhances the ability to complex hydrophobic substrates of appropriate size and shape. In this study, spectrophotometry has been used to investigate the effects of cyclodextrin on the solubility, stoichiometry and stability of the substrate-CD complex formed between N-(2-ethylphenyl)-N'-(2-methylphenyl) thiourea, (a hydrophobic substrate trap) and hydroxypropyl-β-cyclodextrin (HP−β−CD). The solubility, stoichiometry and overall association constant of the complex have been determined using the Higuchi's method, the continuous variation (Job's plot) method and the Scott's method respectively.
{"title":"Inclusion Complex of Thiourea Substrate with Hydroxypropyl-β-cyclodextrin","authors":"A. Allouch, I. Hassan, Adib Abou Dalle, H. El-Nakat, F. Omar","doi":"10.7598/CST2013.402","DOIUrl":"https://doi.org/10.7598/CST2013.402","url":null,"abstract":"To be active, a heavy metal trap substrate must possess some degree of aqueous solubility. The use of cyclodextrins molecules, which can form inclusion complexes with the hydrophobic trap substrates, has provided the required solubility through the relatively hydrophobic cavity of native cyclodextrins and their derivatives that enhances the ability to complex hydrophobic substrates of appropriate size and shape. In this study, spectrophotometry has been used to investigate the effects of cyclodextrin on the solubility, stoichiometry and stability of the substrate-CD complex formed between N-(2-ethylphenyl)-N'-(2-methylphenyl) thiourea, (a hydrophobic substrate trap) and hydroxypropyl-β-cyclodextrin (HP−β−CD). The solubility, stoichiometry and overall association constant of the complex have been determined using the Higuchi's method, the continuous variation (Job's plot) method and the Scott's method respectively.","PeriodicalId":10087,"journal":{"name":"Chemical science transactions","volume":"37 1","pages":"663-669"},"PeriodicalIF":0.0,"publicationDate":"2013-04-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90133460","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
P. P. Deohate, Shri Radhakisan, Laxminarayan Toshniwal
A series of {4-(4-(6-substituted-benzothiazol-2-yl-amino)-3-carboxy-benzyl)-2-carboxy- phenyl}-6-substituted-benzothiazol-2-yl-amines have been synthesized by oxidative cyclization of 1-{4-(4-(3-aryl thiocarbamido)-3-carboxy-benzyl)-2-carboxy-phenyl}-3-aryl thiocarbamides using the solution of bromine in chloroform followed by the basification with dilute ammonium hydroxide solution. Initially 1-{4-(4-(3-aryl thiocarbamido)-3-carboxy-benzyl)-2-carboxy-phenyl}-3-aryl thio- carbamides were prepared by the interaction of different aryl isothiocyanates with 4,4'-methylene- bis-(anthranilic acid). The latter was obtained by treating the mixture of anthranilic acid and concentrated hydrochloric acid with 3% aqueous formaldehyde followed by neutralization with sodium hydroxide. The acetylation of bis-benzothiazoles afforded di-acetyl derivatives. The structures of synthesized compounds have been established on the basis of chemical transformation, elemental analysis, equivalent weight determination and IR, 1 H NMR spectral studies. The title compounds have been assayed for their biological activity against gram-positive as well as gram- negative microorganisms.
{"title":"Synthesis, Structural Study and Antimicrobial Screening of Substituted Bis-benzothiazole Derivatives","authors":"P. P. Deohate, Shri Radhakisan, Laxminarayan Toshniwal","doi":"10.7598/CST2013.414","DOIUrl":"https://doi.org/10.7598/CST2013.414","url":null,"abstract":"A series of {4-(4-(6-substituted-benzothiazol-2-yl-amino)-3-carboxy-benzyl)-2-carboxy- phenyl}-6-substituted-benzothiazol-2-yl-amines have been synthesized by oxidative cyclization of 1-{4-(4-(3-aryl thiocarbamido)-3-carboxy-benzyl)-2-carboxy-phenyl}-3-aryl thiocarbamides using the solution of bromine in chloroform followed by the basification with dilute ammonium hydroxide solution. Initially 1-{4-(4-(3-aryl thiocarbamido)-3-carboxy-benzyl)-2-carboxy-phenyl}-3-aryl thio- carbamides were prepared by the interaction of different aryl isothiocyanates with 4,4'-methylene- bis-(anthranilic acid). The latter was obtained by treating the mixture of anthranilic acid and concentrated hydrochloric acid with 3% aqueous formaldehyde followed by neutralization with sodium hydroxide. The acetylation of bis-benzothiazoles afforded di-acetyl derivatives. The structures of synthesized compounds have been established on the basis of chemical transformation, elemental analysis, equivalent weight determination and IR, 1 H NMR spectral studies. The title compounds have been assayed for their biological activity against gram-positive as well as gram- negative microorganisms.","PeriodicalId":10087,"journal":{"name":"Chemical science transactions","volume":"99 1","pages":"473-478"},"PeriodicalIF":0.0,"publicationDate":"2013-04-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89265781","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The volumetric and viscometric studies of glucose, fructose, sucrose and maltose have been determined in 0.05 M and 0.5 M KCl solutions at 298.15, 303.15, 308.15 and 313.15 K. The apparent molar volume (φv) values vary linearly with square root of concentration of KCl solution. The limiting apparent molar volume (φ 0 v) has been interpreted in terms of solute-solvent interaction. The φ 0 v values vary with temperature and can be represented in the power series of structure making and breaking capacity of electrolyte is inferred from the sign of dB/dT values. The apparent molar expansibility has also been determined. Glucose, fructose, sucrose and maltose have been found to be structure maker and breaker in aqueous KCl from molar volume as well as viscosity studies.
葡萄糖、果糖、蔗糖和麦芽糖在0.05 M和0.5 M KCl溶液中，在298.15、303.15、308.15和313.15 K下进行了体积学和粘度学研究。表观摩尔体积(φv)值随KCl溶液浓度的平方根呈线性变化。极限表观摩尔体积(φ 0 v)用溶质-溶剂相互作用来解释。φ 0 v值随温度变化，可以用结构的幂级数表示，通过dB/dT值的符号可以推断电解液的破断能力。测定了表观摩尔膨胀率。葡萄糖、果糖、蔗糖和麦芽糖从摩尔体积和粘度的研究中发现在氯化钾水溶液中是结构的制造者和破坏者。
{"title":"Study of Structure Making/Breaking Properties of Glucose, Fructose, Sucrose and Maltose in Aqueous KCl at Various Temperatures","authors":"K. Kapadnis, A. P. Hiray","doi":"10.7598/CST2013.421","DOIUrl":"https://doi.org/10.7598/CST2013.421","url":null,"abstract":"The volumetric and viscometric studies of glucose, fructose, sucrose and maltose have been determined in 0.05 M and 0.5 M KCl solutions at 298.15, 303.15, 308.15 and 313.15 K. The apparent molar volume (φv) values vary linearly with square root of concentration of KCl solution. The limiting apparent molar volume (φ 0 v) has been interpreted in terms of solute-solvent interaction. The φ 0 v values vary with temperature and can be represented in the power series of structure making and breaking capacity of electrolyte is inferred from the sign of dB/dT values. The apparent molar expansibility has also been determined. Glucose, fructose, sucrose and maltose have been found to be structure maker and breaker in aqueous KCl from molar volume as well as viscosity studies.","PeriodicalId":10087,"journal":{"name":"Chemical science transactions","volume":"390 1","pages":"485-490"},"PeriodicalIF":0.0,"publicationDate":"2013-04-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76597465","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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