Pub Date : 2023-11-07DOI: 10.1007/s12039-023-02228-4
Satish Wakchaure, Kiran Nathe, Sharayu Deshmukh
An efficient metal-free synthesis of aryl bromides from aniline derivatives using molecular bromine is described. This one-pot reaction affords aryl bromides from corresponding electron-rich anilines in moderate to excellent yields without isolation of diazonium salts. The transformation has short reaction times, an ambient temperature, a simple workup, and insensitivity to moisture and air. This synthetic strategy represents an alternative approach to the classic Sandmeyer reaction.
Graphical abstract
A Metal-free Sandmeyer reaction strategy has been used to synthesize various aryl bromides. An aryl amines have diazotized by using sodium nitrite and 48% HBr in water and subsequently reaction mass treated with liquid bromine to offord variety of aryl bromides. Around 12 different aryl amines have been studied. Excellent yield has been obtained from electron rich aryl amine.
{"title":"A facile, metal-free synthesis of aryl bromides using molecular bromine-an alternative to the Sandmeyer reaction","authors":"Satish Wakchaure, Kiran Nathe, Sharayu Deshmukh","doi":"10.1007/s12039-023-02228-4","DOIUrl":"10.1007/s12039-023-02228-4","url":null,"abstract":"<div><p>An efficient metal-free synthesis of aryl bromides from aniline derivatives using molecular bromine is described. This one-pot reaction affords aryl bromides from corresponding electron-rich anilines in moderate to excellent yields without isolation of diazonium salts. The transformation has short reaction times, an ambient temperature, a simple workup, and insensitivity to moisture and air. This synthetic strategy represents an alternative approach to the classic Sandmeyer reaction.</p><div><figure><div><div><picture><source><img></source></picture></div></div></figure></div><h3>Graphical abstract</h3><p>A Metal-free Sandmeyer reaction strategy has been used to synthesize various aryl bromides. An aryl amines have diazotized by using sodium nitrite and 48% HBr in water and subsequently reaction mass treated with liquid bromine to offord variety of aryl bromides. Around 12 different aryl amines have been studied. Excellent yield has been obtained from electron rich aryl amine.</p><div><figure><div><div><picture><source><img></source></picture></div></div></figure></div></div>","PeriodicalId":616,"journal":{"name":"Journal of Chemical Sciences","volume":null,"pages":null},"PeriodicalIF":1.7,"publicationDate":"2023-11-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134795811","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-11-02DOI: 10.1007/s12039-023-02224-8
Ilyas S Nizamov, Georgiy G Shumatbaev, Ilnar D Nizamov, Varis R Urazbakhtin, Marina P Shulaeva, Oscar K Pozdeev, Elvira S Batyeva
Optically active dithiophosphoric and dithiophosphonic acids bearing glucofuranose and galactopyranose diacetonide substituents reacted with racemic atropine to give atropinium dithiophosphates or dithiophosphonates as the mixture of diastereomers. Dithiophosphoric and dithiophosphonic acids and their atropinium salts possess antimicrobial activity.
Graphical abstract
SYNOPSIS: Optically active dithiophosphoric and dithiophosphonic acids bearing α-D-glucofuranose and α-D-galactopyranose diacetonide substituents reacted with racemic atropine to give atropinium dithiophosphates or dithiophosphonates as the mixture of diastereomers. Dithiophosphoric and dithiophosphonic acids and their atropinium salts possess antimicrobial activity.
具有光学活性的二硫代磷酸和二硫代膦酸，含葡萄糖醛酸和半乳糖醛酸二丙酮取代基，与外消旋阿托品反应得到二硫代磷酸阿托品或二硫代膦酸酯作为非对映体的混合物。二硫代磷酸和二硫代膦酸及其阿托品盐具有抗菌活性。摘要:含α- d -葡萄糖醛酸和α- d -半乳糖醛酸取代基的光活性二硫代磷酸和二硫代膦酸与外消旋阿托品反应得到二硫代磷酸阿托品或二硫代膦酸酯作为非对映体的混合物。二硫代磷酸和二硫代膦酸及其阿托品盐具有抗菌活性。
{"title":"Atropinium dithiophosphates and dithiophosphonates on the basis of α-D-glucofuranose and α-D-galactopyranose diacetonide scaffolds","authors":"Ilyas S Nizamov, Georgiy G Shumatbaev, Ilnar D Nizamov, Varis R Urazbakhtin, Marina P Shulaeva, Oscar K Pozdeev, Elvira S Batyeva","doi":"10.1007/s12039-023-02224-8","DOIUrl":"10.1007/s12039-023-02224-8","url":null,"abstract":"<div><p>Optically active dithiophosphoric and dithiophosphonic acids bearing glucofuranose and galactopyranose diacetonide substituents reacted with racemic atropine to give atropinium dithiophosphates or dithiophosphonates as the mixture of diastereomers. Dithiophosphoric and dithiophosphonic acids and their atropinium salts possess antimicrobial activity.</p><h3>Graphical abstract</h3><p><b>SYNOPSIS:</b> Optically active dithiophosphoric and dithiophosphonic acids bearing α-D-glucofuranose and α-D-galactopyranose diacetonide substituents reacted with racemic atropine to give atropinium dithiophosphates or dithiophosphonates as the mixture of diastereomers. Dithiophosphoric and dithiophosphonic acids and their atropinium salts possess antimicrobial activity.</p>\u0000 <div><figure><div><div><picture><img></picture></div></div></figure></div>\u0000 </div>","PeriodicalId":616,"journal":{"name":"Journal of Chemical Sciences","volume":null,"pages":null},"PeriodicalIF":1.7,"publicationDate":"2023-11-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134795397","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-10-13DOI: 10.1007/s12039-023-02222-w
Suman K Choudhury, D Sivaramakrishna, Musti J Swamy
N-acyl serinols, the amphiphilic molecules produced by gastrointestinal bacteria regulate metabolic hormone production and glucose homeostasis in the host species, and also exhibit anti-cancer activity. In this study, molecular structure, supramolecular organization and intermolecular interactions of two N-acylserinols (NASOHs), viz., N-nonanoylserinol (N9SOH) and N-pentadecanoylserinol (N15SOH), are determined by single-crystal X-ray diffraction. The molecular structure and packing are compared and discussed with the structurally related molecules, N-acylethanolamine (NAE) and N-acyl tris (NAT) as NASOHs and NATs are derived by substituting one/two α-hydrogen(s) (with respect to amide N-H) of NAE with hydroxymethyl group(s). Structures of N9SOH and N15SOH were solved in the triclinic system in the P-1 space group and both molecules are organized in a tilted head-to-head (and tail-to-tail) manner, resembling a bilayer membrane. The acyl chains in N9SOH and N15SOH are tilted by 20.43° and 18.12°, respectively, with respect to the bilayer normal. Several N—H⋯O, O—H⋯O, and C—H⋯O hydrogen bonds between the hydroxyl and amide moieties of the head groups of NASOH molecules belonging to adjacent and opposite layers stabilize the overall supramolecular organization. These results suggest that the α-hydroxymethyl groups exhibit considerable influence on the crystal structure, molecular packing, and phase structure of these amphiphiles.
Graphical abstract
Removing one of the CH2OH moieties of N-acylserinol gives N-acylethanolamine, whereas introducing one more CH2OH moiety on the α-carbon gives N-acyltris. While both N-acylethanolamine and N-acylserinol adopt tilted bilayer structure, the larger head group of N-acyltris induces it to adopt an interdigitated bilayer structure.
n -酰基丝氨酸醇是胃肠道细菌产生的两亲分子，可调节宿主体内代谢激素的产生和葡萄糖稳态，并具有抗癌活性。本研究利用单晶x射线衍射测定了n -壬烷基丝氨酸醇(N9SOH)和n -五烷基丝氨酸醇(N15SOH)两种n -酰基丝氨酸醇(NASOHs)的分子结构、超分子组织和分子间相互作用。与结构相关分子n -酰基乙醇胺(NAE)和n -酰基三醇胺(NAT)的分子结构和排列进行了比较和讨论，NASOHs和NATs是由NAE的1 / 2个α-氢(相对于酰胺N-H)取代羟基(s)而得到的。N9SOH和N15SOH的结构在P-1空间基团的三斜体系中被解析，两种分子以倾斜的头对头(和尾对尾)的方式组织，类似于双层膜。N9SOH和N15SOH中的酰基链相对于双分子层正线分别倾斜20.43°和18.12°。几个N-H⋯O, O - h⋯O和C-H⋯O氢键在NASOH分子的羟基和酰胺基团之间，属于相邻和相反的层，稳定了整个超分子组织。结果表明，α-羟甲基对两亲体的晶体结构、分子堆积和相结构有较大的影响。图摘要:去掉n -酰基丝氨酸醇的一个CH2OH基团得到n -酰基乙醇胺，而在α-碳上再引入一个CH2OH基团得到n -酰基三聚体。n -酰基乙醇胺和n -酰基丝氨酸醇均采用倾斜的双层结构，但n -酰基三聚体头部基团较大，导致其采用交错的双层结构。
{"title":"Structure and supramolecular organization of N-acylserinols: agonists of the G-protein coupled receptor, GPR-119","authors":"Suman K Choudhury, D Sivaramakrishna, Musti J Swamy","doi":"10.1007/s12039-023-02222-w","DOIUrl":"10.1007/s12039-023-02222-w","url":null,"abstract":"<div><p><i>N</i>-acyl serinols, the amphiphilic molecules produced by gastrointestinal bacteria regulate metabolic hormone production and glucose homeostasis in the host species, and also exhibit anti-cancer activity. In this study, molecular structure, supramolecular organization and intermolecular interactions of two <i>N</i>-acylserinols (NASOHs), <i>viz.</i>,<i> N</i>-nonanoylserinol (N9SOH) and <i>N</i>-pentadecanoylserinol (N15SOH), are determined by single-crystal X-ray diffraction. The molecular structure and packing are compared and discussed with the structurally related molecules, <i>N</i>-acylethanolamine (NAE) and <i>N</i>-acyl tris (NAT) as NASOHs and NATs are derived by substituting one/two α-hydrogen(s) (with respect to amide N-H) of NAE with hydroxymethyl group(s). Structures of N9SOH and N15SOH were solved in the triclinic system in the <i>P-1</i> space group and both molecules are organized in a tilted head-to-head (and tail-to-tail) manner, resembling a bilayer membrane. The acyl chains in N9SOH and N15SOH are tilted by 20.43° and 18.12°, respectively, with respect to the bilayer normal. Several N—H⋯O, O—H⋯O, and C—H⋯O hydrogen bonds between the hydroxyl and amide moieties of the head groups of NASOH molecules belonging to adjacent and opposite layers stabilize the overall supramolecular organization. These results suggest that the α-hydroxymethyl groups exhibit considerable influence on the crystal structure, molecular packing, and phase structure of these amphiphiles.</p><h3>Graphical abstract</h3><p>Removing one of the CH<sub>2</sub>OH moieties of <i>N</i>-acylserinol gives <i>N</i>-acylethanolamine, whereas introducing one more CH<sub>2</sub>OH moiety on the α-carbon gives <i>N</i>-acyltris. While both <i>N</i>-acylethanolamine and <i>N</i>-acylserinol adopt tilted bilayer structure, the larger head group of <i>N</i>-acyltris induces it to adopt an interdigitated bilayer structure.</p><div><figure><div><div><picture><source><img></source></picture></div></div></figure></div></div>","PeriodicalId":616,"journal":{"name":"Journal of Chemical Sciences","volume":null,"pages":null},"PeriodicalIF":1.7,"publicationDate":"2023-10-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s12039-023-02222-w.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134796418","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The present study deals with a highly efficient and regioselective synthesis of 7-aryl-5-methyl- and 5-aryl-7-trifluoromethyl-2-amino-3-(4′-arylazo)-pyrazolo[1,5-a]pyrimidines via multicomponent reaction of hydrazine hydrate, 2-(arylhydrazono)malononitrile and β-diketones in presence of p-toluenesulphonic acid under solvent-free condition. The structure of the isolated products was established on the basis of NMR (1H, 13C, and 19F) and IR spectral data. The scope of the reaction was studied using various β-diketones viz., aliphatic, aromatic, heteroaromatic, and trifluoromethyl-β-diketones. The protocol has several advantages, such as mild conditions, atom economy, practical simplicity, shorter reaction times, and avoidance of multi-step procedures. Seventeen diversely substituted pyrazolo[1,5-a]pyrimidines were screened against two breast cancer cell lines, named MCF-7 and BT474, and two leukemia cell lines, named NALM-6 and SB-ALL, using the MTT cytotoxicity assay. Preliminary results reveal that compound 2-amino-5-(4-bromophenyl)-3-(4-methoxyphenylazo)-7-(trifluoromethyl)pyrazolo[1,5-a]pyrimidine was identified as the most effective compound against all the four cancer cell lines with 65-49% cell survival.
Graphical abstract
An efficient regioselective synthesis of 7-aryl-5-methyl- and 5-aryl-7-trifluoromethyl-2-amino-3-(4′-arylazo)-pyrazolo[1,5-a]pyrimidines is developed using solvent-free sequential multicomponent reaction of hydrazine hydrate, 2-(arylhydrazono)malononitrile with unsymmetrical β-diketones.
{"title":"Multicomponent regioselective synthesis of 7-aryl-5-methyl- and 5-aryl-7-trifluoromethyl-2-amino-3-(4′-arylazo)-pyrazolo[1,5-a]pyrimidines and their cytotoxic evaluation","authors":"Ranjana Aggarwal, Suresh Kumar, Garima Sumran, Virender Kumar, Rachna Sadana","doi":"10.1007/s12039-023-02219-5","DOIUrl":"10.1007/s12039-023-02219-5","url":null,"abstract":"<div><p>The present study deals with a highly efficient and regioselective synthesis of 7-aryl-5-methyl- and 5-aryl-7-trifluoromethyl-2-amino-3-(4′-arylazo)-pyrazolo[1,5-<i>a</i>]pyrimidines <i>via</i> multicomponent reaction of hydrazine hydrate, 2-(arylhydrazono)malononitrile and <i>β</i>-diketones in presence of <i>p</i>-toluenesulphonic acid under solvent-free condition. The structure of the isolated products was established on the basis of NMR (<sup>1</sup>H, <sup>13</sup>C, and <sup>19</sup>F) and IR spectral data. The scope of the reaction was studied using various <i>β</i>-diketones <i>viz.,</i> aliphatic, aromatic, heteroaromatic, and trifluoromethyl-<i>β</i>-diketones. The protocol has several advantages, such as mild conditions, atom economy, practical simplicity, shorter reaction times, and avoidance of multi-step procedures. Seventeen diversely substituted pyrazolo[1,5-<i>a</i>]pyrimidines were screened against two breast cancer cell lines, named MCF-7 and BT474, and two leukemia cell lines, named NALM-6 and SB-ALL, using the MTT cytotoxicity assay. Preliminary results reveal that compound 2-amino-5-(4-bromophenyl)-3-(4-methoxyphenylazo)-7-(trifluoromethyl)pyrazolo[1,5-<i>a</i>]pyrimidine was identified as the most effective compound against all the four cancer cell lines with 65-49% cell survival.</p><h3>Graphical abstract</h3><p>An efficient regioselective synthesis of 7-aryl-5-methyl- and 5-aryl-7-trifluoromethyl-2-amino-3-(4′-arylazo)-pyrazolo[1,5-<i>a</i>]pyrimidines is developed using solvent-free sequential multicomponent reaction of hydrazine hydrate, 2-(arylhydrazono)malononitrile with unsymmetrical <i>β</i>-diketones.</p><div><figure><div><div><picture><source><img></source></picture></div></div></figure></div></div>","PeriodicalId":616,"journal":{"name":"Journal of Chemical Sciences","volume":null,"pages":null},"PeriodicalIF":1.7,"publicationDate":"2023-10-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134796419","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
In this report, CuBi2O4 and CuBi2O4/MnO2 are synthesized using coprecipitation and hydrothermal methods, respectively. CuBi2O4/MnO2 has been extensively used for the electrochemical detection of hydroxylamine. CuBi2O4 and CuBi2O4/MnO2 are well characterized by XRD, XPS, and FESEM to reveal the structural and morphological features of the material. Electrochemical measurements like CV, chronoamperometry, and impedance are studied to reveal the electrochemical behavior of CuBi2O4/MnO2 towards hydroxylamine. Stability, reproducibility, and interference studies are performed to reveal the suitability of CuBi2O4/MnO2 as an electrode material for the electrochemical detection of hydroxylamine.
Graphical abstract
CuBi2O4 and CuBi2O4/MnO2 are synthesized using coprecipitation and hydrothermal methods, respectively, and tested for the electrochemical detection of hydroxylamine. CuBi2O4/MnO2 exhibited a high sensitivity of 488 μA mM−1 cm−2 with a limit of detection 0.86 μM, revealing its ability to display good electrochemical activity towards hydroxylamine.
{"title":"MnO2 and CuBi2O4 hybrid microstructures for efficient nonenzymatic hydroxylamine detection","authors":"Neeraja Sinha Gudipati, Asha Ramesh, Sivaramakrishna Vanjari, Suryakala Duvvuri, Subrahmanyam Challapalli","doi":"10.1007/s12039-023-02221-x","DOIUrl":"10.1007/s12039-023-02221-x","url":null,"abstract":"<div><p>In this report, CuBi<sub>2</sub>O<sub>4</sub> and CuBi<sub>2</sub>O<sub>4</sub>/MnO<sub>2</sub> are synthesized using coprecipitation and hydrothermal methods, respectively. CuBi<sub>2</sub>O<sub>4</sub>/MnO<sub>2</sub> has been extensively used for the electrochemical detection of hydroxylamine. CuBi<sub>2</sub>O<sub>4</sub> and CuBi<sub>2</sub>O<sub>4</sub>/MnO<sub>2</sub> are well characterized by XRD, XPS, and FESEM to reveal the structural and morphological features of the material. Electrochemical measurements like CV, chronoamperometry, and impedance are studied to reveal the electrochemical behavior of CuBi<sub>2</sub>O<sub>4</sub>/MnO<sub>2</sub> towards hydroxylamine. Stability, reproducibility, and interference studies are performed to reveal the suitability of CuBi<sub>2</sub>O<sub>4</sub>/MnO<sub>2</sub> as an electrode material for the electrochemical detection of hydroxylamine.</p><h3>Graphical abstract</h3><p>CuBi2O4 and CuBi2O4/MnO2 are synthesized using coprecipitation and hydrothermal methods, respectively, and tested for the electrochemical detection of hydroxylamine. CuBi2O4/MnO2 exhibited a high sensitivity of 488 μA mM<sup>−1</sup> cm<sup>−2</sup> with a limit of detection 0.86 μM, revealing its ability to display good electrochemical activity towards hydroxylamine.</p><div><figure><div><div><picture><source><img></source></picture></div></div></figure></div></div>","PeriodicalId":616,"journal":{"name":"Journal of Chemical Sciences","volume":null,"pages":null},"PeriodicalIF":1.7,"publicationDate":"2023-10-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134796122","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-09-15DOI: 10.1007/s12039-023-02216-8
Ram P Gokula, Abhishek Tripathi, Selvakumar Karuthapandi, Harkesh B Singh
The development of straightforward synthetic and characterization methods for selenopeptides is essential to discovering hierarchical structured functional materials. Here, the synthesis of a series of homo-selenopeptides 1-4, having the benzyl (Bzl) group-protected selenocysteine [(Bzl)SeCH2CH(NH2)COOH] monomer units in the sequence, is reported. The homo-selenopeptides 1-4 are characterized by 1D (1H, 13C, and 77Se) and 2D (1H-1H COSY, 1H-1H NOESY, and 1H-1H TOCSY) NMR spectroscopy, and ESI-MS spectrometry. The triselenopeptide 1 shows a propensity for self-assembly into β-sheet amyloid-like fibril structure in acetonitrile (ACN) solution at room temperature. This has systematically been analyzed and established through the spectroscopic techniques; FT-IR, CD, and ThT-based fluorescence spectroscopy for secondary bonding analyses and microscopic techniques; SEM and TEM for the amyloid-like fibril structure in ACN solution. The amide I band vibrational stretching frequencies observed in the range 1600-1700 cm−1 confirm that all peptides in the homologous series have a strong propensity to form amyloid-like fibril structures.
Graphical abstract
Synthesis of a series of homo-selenopeptides 1-4 through the solid-phase peptide synthesis (SPPS), using Fmoc protected Sec(Bzl)-OH as a source of amino acid, has been described. Spectroscopic and morphological imaging studies revealed that the homo-selenopeptides have a high propensity to get self-organized into amyloid-like fibrillar structures.
{"title":"Studies on syntheses and self-assembly behaviour of homoseleno-peptides","authors":"Ram P Gokula, Abhishek Tripathi, Selvakumar Karuthapandi, Harkesh B Singh","doi":"10.1007/s12039-023-02216-8","DOIUrl":"10.1007/s12039-023-02216-8","url":null,"abstract":"<div><p>The development of straightforward synthetic and characterization methods for selenopeptides is essential to discovering hierarchical structured functional materials. Here, the synthesis of a series of homo-selenopeptides <b>1-4,</b> having the benzyl (Bzl) group-protected selenocysteine [(Bzl)SeCH<sub>2</sub>CH(NH<sub>2</sub>)COOH] monomer units in the sequence, is reported. The homo-selenopeptides <b>1-4</b> are characterized by 1D (<sup>1</sup>H, <sup>13</sup>C, and <sup>77</sup>Se) and 2D (<sup>1</sup>H-<sup>1</sup>H COSY, <sup>1</sup>H-<sup>1</sup>H NOESY, and <sup>1</sup>H-<sup>1</sup>H TOCSY) NMR spectroscopy, and ESI-MS spectrometry. The triselenopeptide <b>1</b> shows a propensity for self-assembly into β-sheet amyloid-like fibril structure in acetonitrile (ACN) solution at room temperature. This has systematically been analyzed and established through the spectroscopic techniques; FT-IR, CD, and ThT-based fluorescence spectroscopy for secondary bonding analyses and microscopic techniques; SEM and TEM for the amyloid-like fibril structure in ACN solution. The amide I band vibrational stretching frequencies observed in the range 1600-1700 cm<sup>−1</sup> confirm that all peptides in the homologous series have a strong propensity to form amyloid-like fibril structures.</p><h3>Graphical abstract</h3><p>Synthesis of a series of homo-selenopeptides <b>1</b>-<b>4</b> through the solid-phase peptide synthesis (SPPS), using Fmoc protected Sec(Bzl)-OH as a source of amino acid, has been described. Spectroscopic and morphological imaging studies revealed that the homo-selenopeptides have a high propensity to get self-organized into amyloid-like fibrillar structures.</p><div><figure><div><div><picture><source><img></source></picture></div></div></figure></div></div>","PeriodicalId":616,"journal":{"name":"Journal of Chemical Sciences","volume":null,"pages":null},"PeriodicalIF":1.7,"publicationDate":"2023-09-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134796891","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-09-11DOI: 10.1007/s12039-023-02218-6
P Aswin, Soumya B Narendranath, Arya Unni, S Balamurugan, N J Venkatesha, A Sakthivel
The molybdate-incorporated hydrotalcite-type α-Ni(OH)2 catalysts were prepared by the post-synthesis method. The synthesized catalyst was thoroughly studied using several physicochemical characterization methods. The catalytic activity of the material was studied on biomass model compounds such as anisole hydrotreating and the oxidation of iso-eugenol. The catalyst shows a significant conversion for the anisole hydrotreating in vapour phase conditions, yielding a steady-state conversion of 30% even after 10 h of time-on-stream (TOS). The primary product was benzene, with other products, viz., methyl anisole, methylcyclohexane, and toluene, as minor components. The catalyst also has the potential for iso-eugenol oxidation and shows 76.1% conversion with 75.5% selectivity for vanillin at 100 °C, 5 h.
Graphical abstract
Molybdate-incorporated hydrotalcite-type α-Ni(OH)2 catalysts have the potential for oxidation of iso-eugenol to vanillin in the presence of an oxidant in a liquid phase and hydro-deoxygenation in the vapour phase under a hydrogen atmosphere.
{"title":"Molybdate incorporated α-Ni(OH)2: potential catalyst for oxidation of Iso-eugenol and anisole hydrotreating","authors":"P Aswin, Soumya B Narendranath, Arya Unni, S Balamurugan, N J Venkatesha, A Sakthivel","doi":"10.1007/s12039-023-02218-6","DOIUrl":"10.1007/s12039-023-02218-6","url":null,"abstract":"<div><p>The molybdate-incorporated hydrotalcite-type α-Ni(OH)<sub>2</sub> catalysts were prepared by the post-synthesis method. The synthesized catalyst was thoroughly studied using several physicochemical characterization methods. The catalytic activity of the material was studied on biomass model compounds such as anisole hydrotreating and the oxidation of <i>iso</i>-eugenol. The catalyst shows a significant conversion for the anisole hydrotreating in vapour phase conditions, yielding a steady-state conversion of 30% even after 10 h of time-on-stream (TOS). The primary product was benzene, with other products, viz., methyl anisole, methylcyclohexane, and toluene, as minor components. The catalyst also has the potential for <i>iso-</i>eugenol oxidation and shows 76.1% conversion with 75.5% selectivity for vanillin at 100 °C, 5 h.</p><h3>Graphical abstract</h3><p>Molybdate-incorporated hydrotalcite-type α-Ni(OH)<sub>2</sub> catalysts have the potential for oxidation of iso-eugenol to vanillin in the presence of an oxidant in a liquid phase and hydro-deoxygenation in the vapour phase under a hydrogen atmosphere.</p><div><figure><div><div><picture><source><img></source></picture></div></div></figure></div></div>","PeriodicalId":616,"journal":{"name":"Journal of Chemical Sciences","volume":null,"pages":null},"PeriodicalIF":1.7,"publicationDate":"2023-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134796021","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
This work presents a coumarin-anthracene-based chemodosimeter L for the selective detection of Arginine (Arg) via hydrolysis of the imine bond of the Schiff base L. Significant changes in the emission and absorption spectra of L were observed during the detection of Arg. Chemodosimeter L displayed an impressive detection limit of 0.46 μM for Arg by the emission spectral titrations. A combination of UV-Vis, emission, and mass spectral studies, as well as excited-state lifetime measurements, and quantum yield calculations illustrated Arg-assisted dosimetry of L. The sensing of Arg by L was employed in cell imaging and for the colorimetric detection and paper test strip-based practical detection methods.
Graphical abstract
This work presents a chemodosimeter L based on a coumarin-anthracene platform for the selective detection of amino acid arginine.
{"title":"A coumarin-anthracene-based chemodosimeter for the selective detection of arginine","authors":"Devender Singh, Ibrahim Annan, Shivani Tyagi, Vedprakash Meena, Sweta Singh, Rajeev Gupta","doi":"10.1007/s12039-023-02215-9","DOIUrl":"10.1007/s12039-023-02215-9","url":null,"abstract":"<div><p>This work presents a coumarin-anthracene-based chemodosimeter <b>L</b> for the selective detection of Arginine (Arg) <i>via</i> hydrolysis of the imine bond of the Schiff base <b>L</b>. Significant changes in the emission and absorption spectra of <b>L</b> were observed during the detection of Arg. Chemodosimeter <b>L</b> displayed an impressive detection limit of 0.46 μM for Arg by the emission spectral titrations. A combination of UV-Vis, emission, and mass spectral studies, as well as excited-state lifetime measurements, and quantum yield calculations illustrated Arg-assisted dosimetry of <b>L</b>. The sensing of Arg by <b>L</b> was employed in cell imaging and for the colorimetric detection and paper test strip-based practical detection methods.</p><h3>Graphical abstract</h3><p>This work presents a chemodosimeter <b>L</b> based on a coumarin-anthracene platform for the selective detection of amino acid arginine.\u0000</p><figure><div><div><div><picture><source><img></source></picture></div></div></div></figure></div>","PeriodicalId":616,"journal":{"name":"Journal of Chemical Sciences","volume":null,"pages":null},"PeriodicalIF":1.7,"publicationDate":"2023-09-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"6551729","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-09-04DOI: 10.1007/s12039-023-02217-7
Behjat Pouramiri, Mohsen Rashidi
This research is aimed at synthesizing pyrimidine heterocycles that contain 1,3,4-thiadiazole ring moiety by microwave-assisted multi-component reactions. For this purpose, synthesizing of [1,3,4] thiadiazolo[3,2-a]pyrimidine-6-carboxylate derivatives was carried out in a single-step reaction using aromatic aldehydes, ethyl acetoacetate, and different derivatives of 1,3,4-thiadiazoles (with molar ratio of 1:2:1 respectively) in the presence of [Et3NH]+[HSO4]- ionic liquid, under solvent-free conditions.
Graphical abstract
This research, synthesis of [1,3,4] thiadiazolo[3,2-a]pyrimidine-6-carboxylate derivatives was carried out in a single-step reaction using aromatic aldehydes, ethyl acetoacetate and different derivatives of 1,3,4-thiadiazoles (with molar ratio of 1:2:1, respectively) in the presence of [Et3NH]+[HSO4]- ionic liquid under solvent-free microwave irradiation.
{"title":"Microwave-promoted multi-component and green synthesis of thiadiazolo[3,2-a]pyrimidines under solvent-free conditions","authors":"Behjat Pouramiri, Mohsen Rashidi","doi":"10.1007/s12039-023-02217-7","DOIUrl":"10.1007/s12039-023-02217-7","url":null,"abstract":"<div><p>This research is aimed at synthesizing pyrimidine heterocycles that contain 1,3,4-thiadiazole ring moiety by microwave-assisted multi-component reactions. For this purpose, synthesizing of [1,3,4] thiadiazolo[3,2-a]pyrimidine-6-carboxylate derivatives was carried out in a single-step reaction using aromatic aldehydes, ethyl acetoacetate, and different derivatives of 1,3,4-thiadiazoles (with molar ratio of 1:2:1 respectively) in the presence of [Et<sub>3</sub>NH]<sup>+</sup>[HSO<sub>4</sub>]<sup>-</sup> ionic liquid, under solvent-free conditions.</p><h3>Graphical abstract</h3><p>This research, synthesis of [1,3,4] thiadiazolo[3,2-a]pyrimidine-6-carboxylate derivatives was carried out in a single-step reaction using aromatic aldehydes, ethyl acetoacetate and different derivatives of 1,3,4-thiadiazoles (with molar ratio of 1:2:1, respectively) in the presence of [Et<sub>3</sub>NH]<sup>+</sup>[HSO<sub>4</sub>]<sup>-</sup> ionic liquid under solvent-free microwave irradiation.\u0000</p><div><figure><div><div><picture><source><img></source></picture></div></div></figure></div></div>","PeriodicalId":616,"journal":{"name":"Journal of Chemical Sciences","volume":null,"pages":null},"PeriodicalIF":1.7,"publicationDate":"2023-09-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85242430","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2023-08-31DOI: 10.1007/s12039-023-02212-y
Jai Parkash, Sangeeta Saini
Different reaction pathways of CO oxidation at the surface of trimetallic nanoclusters, Au(5-x-y)AgxCuy of varying compositions with 2 ≤ x + y ≤ 4 (x, y > 0) are investigated. The starting point of all pathways is the surface reaction between adsorbed CO and O2via the Langmuir-Hinshelwood mechanism. The conventional reaction pathway leads to the formation of intermediate Au(5-x-y)AgxCuy.O* followed by a reaction with CO to release CO2. However, on these trimetallic clusters, the formation of the nanocluster-carbonate adduct is greatly facilitated, which is known to poison the catalytic surface because of its greater stability. Here, we propose a possible Eley-Rideal (ER) pathway leading to carbonate decomposition and catalytic surface regeneration. This ER-pathway involves interaction between nanocluster-carbonate adduct and CO in the gaseous state, forming Au(5-x-y)AgxCuy.O2COCO*, which decomposes to release CO2. The study suggests the best trimetallic clusters for CO oxidation are the ones where both reaction sites are Ag-sites.
Graphical abstract
Different reaction pathways of CO oxidation at the surface of trimetallic nanoclusters, Au(5-x-y)AgxCuy, are investigated. These include the conventional LH-LH pathway and a newer alternative LH-ER pathway. The proposed LH-ER pathway involves an interaction between nanocluster-carbonate adduct and CO(g), forming Au(5-x-y)AgxCuy.O2COCO*, which decomposes to release CO2.
2≤x + y≤4 (x, y >)三金属纳米团簇Au(5-x-y)AgxCuy表面CO氧化的不同反应途径;0)被调查。所有途径的起点是通过Langmuir-Hinshelwood机制吸附CO和O2之间的表面反应。常规反应途径生成中间产物Au(5-x-y)AgxCuy。O*随后与CO反应释放CO2。然而，在这些三金属簇上，纳米簇-碳酸盐加合物的形成非常容易，由于其更大的稳定性，已知会毒害催化表面。在这里，我们提出了一种可能的Eley-Rideal (ER)途径，导致碳酸盐分解和催化表面再生。这种er途径涉及纳米簇-碳酸盐加合物与气态CO相互作用，形成Au(5-x-y)AgxCuy。O2COCO*，分解释放二氧化碳。研究表明，CO氧化的最佳三金属簇是两个反应位点都是ag位点的簇。摘要研究了三金属纳米团簇Au(5-x-y)AgxCuy表面CO氧化的不同反应途径。这些途径包括传统的LH-LH途径和较新的LH-ER途径。提出的LH-ER途径涉及纳米簇-碳酸盐加合物与CO(g)相互作用，形成Au(5-x-y)AgxCuy。O2COCO*，分解释放二氧化碳。
{"title":"An alternative decomposition reaction pathway for CO oxidation at Au5-x-yAgxCuy (2 ≤ x + y ≤ 4) nanoclusters","authors":"Jai Parkash, Sangeeta Saini","doi":"10.1007/s12039-023-02212-y","DOIUrl":"10.1007/s12039-023-02212-y","url":null,"abstract":"<div><p>Different reaction pathways of CO oxidation at the surface of trimetallic nanoclusters, Au<sub>(5-x-y)</sub>Ag<sub>x</sub>Cu<sub>y</sub> of varying compositions with 2 ≤ x + y ≤ 4 (x, y > 0) are investigated. The starting point of all pathways is the surface reaction between adsorbed CO and O<sub>2</sub> <i>via</i> the Langmuir-Hinshelwood mechanism. The conventional reaction pathway leads to the formation of intermediate Au<sub>(5-x-y)</sub>Ag<sub>x</sub>Cu<sub>y.</sub>O* followed by a reaction with CO to release CO<sub>2</sub>. However, on these trimetallic clusters, the formation of the nanocluster-carbonate adduct is greatly facilitated, which is known to poison the catalytic surface because of its greater stability. Here, we propose a possible Eley-Rideal (ER) pathway leading to carbonate decomposition and catalytic surface regeneration. This ER-pathway involves interaction between nanocluster-carbonate adduct and CO in the gaseous state, forming Au<sub>(5-x-y)</sub>Ag<sub>x</sub>Cu<sub>y.</sub>O<sub>2</sub>COCO*, which decomposes to release CO<sub>2</sub>. The study suggests the best trimetallic clusters for CO oxidation are the ones where both reaction sites are Ag-sites.</p><h3>Graphical abstract</h3><p>Different reaction pathways of CO oxidation at the surface of trimetallic nanoclusters, Au<sub>(5-x-y)</sub>Ag<sub>x</sub>Cu<sub>y</sub>, are investigated. These include the conventional LH-LH pathway and a newer alternative LH-ER pathway. The proposed LH-ER pathway involves an interaction between nanocluster-carbonate adduct and CO(g), forming Au<sub>(5-x-y)</sub>Ag<sub>x</sub>Cu<sub>y</sub>.O<sub>2</sub>COCO*, which decomposes to release CO<sub>2</sub>.</p>\u0000 <div><figure><div><div><picture><source><img></source></picture></div></div></figure></div>\u0000 </div>","PeriodicalId":616,"journal":{"name":"Journal of Chemical Sciences","volume":null,"pages":null},"PeriodicalIF":1.7,"publicationDate":"2023-08-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77303513","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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