ABSTRACT. Among oxygen-containing heterocyclic compounds such as coumarin and azacoumarin derivatives, the scaffold has become an important construction motif for developing new drugs. Coumarin and its derivatives possess many types of biological activities and have been reported to show significant cytotoxic activity. N-(6,8-disubstituted coumarin-3-yl)benzamides (8a-c) namely (3-N-(benzoyl) aminocoumarin-6-ylmethyl acetate (8a); N-[6-(1-acetylpyrazol-3-yldiazineyl) coumarin-3-yl] benzamide (8b); N-(8-methoxy-6-bromo-coumarin-3-yl) benzamide (8c), were synthesized via a cyclocondensation reaction of 5-(chloromethyl)-2-hydroxybenzaldehyde (3), 5-(pyrazol-3-yl-diazineyl)-2-hydroxybenzaldehyde (4), and 5-bromo-3-methoxy- 2-hydroxybenzaldehyde (5) with N-benzoylglycine (7), in good yield. Treatment of compound 8c with ammonia in the presence of anhydrous potassium carbonate to yield N-(5-bromo-8-methoxy-1-azocoumarin-3-yl) benzamide (9). Compound (9) was acetylated with acetic anhydride to give N-(2-acetoxy-5-bromo-8-methoxyquinolin-3-yl) benzamide (10). N-(substituted coumarin and azacoumarin-3-yl) benzamides (8-10) were tested for their in vitro cytotoxic activity against (HepG2) cell line. Furthermore, DNA flow cytometry investigation over HepG2 cells indicated that compound 8a demonstrated arrest at G1/S stages of the cell cycle and induction of apoptosis by rising pre-G1 stage. Compound 8a displayed a significant tubulin polymerization inhibition. KEY WORDS: Synthesis, Coumarin, Azacoumarin, Drugs, Cytotoxicity Bull. Chem. Soc. Ethiop. 2023, 37(4), 1003-1019. DOI: https://dx.doi.org/10.4314/bcse.v37i4.16
{"title":"Design, synthesis, and cytotoxic activity of some novel N-(substituted) benzamide derivatives bearing coumarin and 1-azocoumarin compounds","authors":"G. H. Al-Hazmi","doi":"10.4314/bcse.v37i4.16","DOIUrl":"https://doi.org/10.4314/bcse.v37i4.16","url":null,"abstract":"ABSTRACT. Among oxygen-containing heterocyclic compounds such as coumarin and azacoumarin derivatives, the scaffold has become an important construction motif for developing new drugs. Coumarin and its derivatives possess many types of biological activities and have been reported to show significant cytotoxic activity. N-(6,8-disubstituted coumarin-3-yl)benzamides (8a-c) namely (3-N-(benzoyl) aminocoumarin-6-ylmethyl acetate (8a); N-[6-(1-acetylpyrazol-3-yldiazineyl) coumarin-3-yl] benzamide (8b); N-(8-methoxy-6-bromo-coumarin-3-yl) benzamide (8c), were synthesized via a cyclocondensation reaction of 5-(chloromethyl)-2-hydroxybenzaldehyde (3), 5-(pyrazol-3-yl-diazineyl)-2-hydroxybenzaldehyde (4), and 5-bromo-3-methoxy- 2-hydroxybenzaldehyde (5) with N-benzoylglycine (7), in good yield. Treatment of compound 8c with ammonia in the presence of anhydrous potassium carbonate to yield N-(5-bromo-8-methoxy-1-azocoumarin-3-yl) benzamide (9). Compound (9) was acetylated with acetic anhydride to give N-(2-acetoxy-5-bromo-8-methoxyquinolin-3-yl) benzamide (10). N-(substituted coumarin and azacoumarin-3-yl) benzamides (8-10) were tested for their in vitro cytotoxic activity against (HepG2) cell line. Furthermore, DNA flow cytometry investigation over HepG2 cells indicated that compound 8a demonstrated arrest at G1/S stages of the cell cycle and induction of apoptosis by rising pre-G1 stage. Compound 8a displayed a significant tubulin polymerization inhibition. \u0000 \u0000KEY WORDS: Synthesis, Coumarin, Azacoumarin, Drugs, Cytotoxicity \u0000Bull. Chem. Soc. Ethiop. 2023, 37(4), 1003-1019. \u0000DOI: https://dx.doi.org/10.4314/bcse.v37i4.16","PeriodicalId":9501,"journal":{"name":"Bulletin of the Chemical Society of Ethiopia","volume":" ","pages":""},"PeriodicalIF":1.2,"publicationDate":"2023-05-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41921477","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}
A. Karthick, N. Muthu Saravanan, A. Arul Marcel Moshi, S. Iyahraja
ABSTRACT. Various kinds of biomass fuels are used for boiler and other kinds of thermal applications. The presence of moisture, ash and calorific value are known to be the most significant quality factors which influence the effective performance of a biomass fuel for a plant. The reasons for measuring the above mentioned quality factors are to perform the economic analysis and to control the combustion. The relevant industries are interested to obtain a method for predicting these quality factors quickly and consistently; and also to identify biomass fuels containing optimal level of these factors. In the present work, five different biomass fuels have been considered such as rubber wood, eucalyptus wood, mixed wood (tamarind tree and neem tree woods), palm shell with fiber and juliflora woodchips. The moisture content in the considered woods have been found to be 27.74 wt.%, 37.78%, 30.19 wt.%, 23.26 wt.% and 37.01 wt.% respectively. The main objective of this work is to maximize the efficiency of production. Grey relational analysis has been carried out to optimize the moisture content, ash content and calorific value in order to achieve cost savings and fuel efficiency. Also, the economic analysis has been done with the operational costs. KEY WORDS: Biomass, Fuels, Energy, Boiler, Optimization Bull. Chem. Soc. Ethiop. 2023, 37(4), 1055-1064. DOI: https://dx.doi.org/10.4314/bcse.v37i4.20
{"title":"Multi-response optimization of the characteristics of wooden fuel sources for boiler applications","authors":"A. Karthick, N. Muthu Saravanan, A. Arul Marcel Moshi, S. Iyahraja","doi":"10.4314/bcse.v37i4.20","DOIUrl":"https://doi.org/10.4314/bcse.v37i4.20","url":null,"abstract":"ABSTRACT. Various kinds of biomass fuels are used for boiler and other kinds of thermal applications. The presence of moisture, ash and calorific value are known to be the most significant quality factors which influence the effective performance of a biomass fuel for a plant. The reasons for measuring the above mentioned quality factors are to perform the economic analysis and to control the combustion. The relevant industries are interested to obtain a method for predicting these quality factors quickly and consistently; and also to identify biomass fuels containing optimal level of these factors. In the present work, five different biomass fuels have been considered such as rubber wood, eucalyptus wood, mixed wood (tamarind tree and neem tree woods), palm shell with fiber and juliflora woodchips. The moisture content in the considered woods have been found to be 27.74 wt.%, 37.78%, 30.19 wt.%, 23.26 wt.% and 37.01 wt.% respectively. The main objective of this work is to maximize the efficiency of production. Grey relational analysis has been carried out to optimize the moisture content, ash content and calorific value in order to achieve cost savings and fuel efficiency. Also, the economic analysis has been done with the operational costs. \u0000 \u0000KEY WORDS: Biomass, Fuels, Energy, Boiler, Optimization \u0000Bull. Chem. Soc. Ethiop. 2023, 37(4), 1055-1064. \u0000DOI: https://dx.doi.org/10.4314/bcse.v37i4.20","PeriodicalId":9501,"journal":{"name":"Bulletin of the Chemical Society of Ethiopia","volume":" ","pages":""},"PeriodicalIF":1.2,"publicationDate":"2023-05-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46222658","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}
Vincent Nwalieji Okafor, Daniel Omeodisemi Omokpariola, Matthew Onyema Agu, Collins Chibuzor Odidika, Chiamaka Valerine Okabekwa, Lilian Chiamaka Ogbuo, Mary Cynthia Chizoba Obiatuegwu
ABSTRACT. The aim of this investigation was to assess the presence of 16 PAHs (naphthalene, acenaphthylene, acenaphthene, fluorene, anthracene, phenanthrene fluoranthene, benz[a]anthracene, pyrene, chrysene, benzo[b]fluoranthene, benzo[k]fluoranthene, benzo[a]pyrene, dibenzo[a,h]anthracene, benzo[ghi]perylene, and indeno[1,2,3-cd]pyrene with symbols Nap, Ace, Ane, Flu, Ant, Phe, Flt, BaA, Pyr, Chr, BbF, BkF, BaP, DahA, BghiP and InP, respectively) in alcoholic beverages consumed in Awka, Southeast Nigeria. The samples used were sourced from international, national, and local-based alcoholic beverages sold in Nigeria, which were analysed for the 16 priority PAHs components using gas chromatography-flame ionization detector (GC-FID) in order to quantify and offer advice to the public on the health implications of consuming these alcoholic beverages. The results show the absence of all the PAHs in all the alcoholic beverages, which could be due to lower temperature and shorter production duration utilized in the production process. This is because during the intense heating of raw materials or additives, PAHs are released. Therefore, the consumption of these alcoholic beverages is safe for consumers and poses no health risk that is detrimental to adults or children. As such, further research into other micropollutants and toxins is advocated to maintain current good manufacturing practices for quality. KEY WORDS: Alcoholic beverages, Food analysis, Public health, PAHs, GC-FID, Southeast Nigeria Bull. Chem. Soc. Ethiop. 2023, 37(4), 805-815. DOI: https://dx.doi.org/10.4314/bcse.v37i4.1
{"title":"Assessment of polycyclic aromatic hydrocarbons (PAHs) in alcoholic beverages consumed in Awka, Southeast Nigeria","authors":"Vincent Nwalieji Okafor, Daniel Omeodisemi Omokpariola, Matthew Onyema Agu, Collins Chibuzor Odidika, Chiamaka Valerine Okabekwa, Lilian Chiamaka Ogbuo, Mary Cynthia Chizoba Obiatuegwu","doi":"10.4314/bcse.v37i4.1","DOIUrl":"https://doi.org/10.4314/bcse.v37i4.1","url":null,"abstract":"ABSTRACT. The aim of this investigation was to assess the presence of 16 PAHs (naphthalene, acenaphthylene, acenaphthene, fluorene, anthracene, phenanthrene fluoranthene, benz[a]anthracene, pyrene, chrysene, benzo[b]fluoranthene, benzo[k]fluoranthene, benzo[a]pyrene, dibenzo[a,h]anthracene, benzo[ghi]perylene, and indeno[1,2,3-cd]pyrene with symbols Nap, Ace, Ane, Flu, Ant, Phe, Flt, BaA, Pyr, Chr, BbF, BkF, BaP, DahA, BghiP and InP, respectively) in alcoholic beverages consumed in Awka, Southeast Nigeria. The samples used were sourced from international, national, and local-based alcoholic beverages sold in Nigeria, which were analysed for the 16 priority PAHs components using gas chromatography-flame ionization detector (GC-FID) in order to quantify and offer advice to the public on the health implications of consuming these alcoholic beverages. The results show the absence of all the PAHs in all the alcoholic beverages, which could be due to lower temperature and shorter production duration utilized in the production process. This is because during the intense heating of raw materials or additives, PAHs are released. Therefore, the consumption of these alcoholic beverages is safe for consumers and poses no health risk that is detrimental to adults or children. As such, further research into other micropollutants and toxins is advocated to maintain current good manufacturing practices for quality. \u0000KEY WORDS: Alcoholic beverages, Food analysis, Public health, PAHs, GC-FID, Southeast Nigeria \u0000 \u0000Bull. Chem. Soc. Ethiop. 2023, 37(4), 805-815. \u0000DOI: https://dx.doi.org/10.4314/bcse.v37i4.1 \u0000 ","PeriodicalId":9501,"journal":{"name":"Bulletin of the Chemical Society of Ethiopia","volume":" ","pages":""},"PeriodicalIF":1.2,"publicationDate":"2023-05-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49414540","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}
R. Sreedevi, A. S.I. Joy Sinthiya, T. Joselin Beaula, T. Balu, P. Murugakoothan
ABSTRACT. Nonlinear optical (NLO) active guanidinium trichloroacetate (GTCA) crystal was synthesised and grown by using slow evaporation solution growth technique from mixed solvent. The grown crystal was characterized by single crystal X-ray diffraction (SXRD) and powder X-ray diffraction (PXRD) analysis. Fourier transform infrared (FTIR) spectrum of GTCA was recorded and the frequency assignments of various functional groups were compared with theoretical values. Mechanical strength of the grown crystal was studied using Vickers micro hardness tester. Thermal stability was studied using TG/DTA analyser. UV-Vis-NIR spectrum was recorded and the band gap energy was calculated. Geometry optimizations, first order hyperpolarizability, HOMO-LUMO energy gap, global reactive constants, thermodynamic properties, molecular electrostatic potential (MESP) and charge population were computed using B3LYP/6-31 G(d,p) basis set and DFT method and analysed. KEY WORDS: PXRD, FTIR, TG-DTA, DFT, NBO, Charge population Bull. Chem. Soc. Ethiop. 2023, 37(4), 1033-1045. DOI: https://dx.doi.org/10.4314/bcse.v37i4.18
{"title":"Growth, characterization and chemical computations of guanidinium trichloroacetate (GTCA) single crystal – DFT approach","authors":"R. Sreedevi, A. S.I. Joy Sinthiya, T. Joselin Beaula, T. Balu, P. Murugakoothan","doi":"10.4314/bcse.v37i4.18","DOIUrl":"https://doi.org/10.4314/bcse.v37i4.18","url":null,"abstract":"ABSTRACT. Nonlinear optical (NLO) active guanidinium trichloroacetate (GTCA) crystal was synthesised and grown by using slow evaporation solution growth technique from mixed solvent. The grown crystal was characterized by single crystal X-ray diffraction (SXRD) and powder X-ray diffraction (PXRD) analysis. Fourier transform infrared (FTIR) spectrum of GTCA was recorded and the frequency assignments of various functional groups were compared with theoretical values. Mechanical strength of the grown crystal was studied using Vickers micro hardness tester. Thermal stability was studied using TG/DTA analyser. UV-Vis-NIR spectrum was recorded and the band gap energy was calculated. Geometry optimizations, first order hyperpolarizability, HOMO-LUMO energy gap, global reactive constants, thermodynamic properties, molecular electrostatic potential (MESP) and charge population were computed using B3LYP/6-31 G(d,p) basis set and DFT method and analysed. \u0000 \u0000KEY WORDS: PXRD, FTIR, TG-DTA, DFT, NBO, Charge population \u0000 \u0000Bull. Chem. Soc. Ethiop. 2023, 37(4), 1033-1045. \u0000DOI: https://dx.doi.org/10.4314/bcse.v37i4.18 ","PeriodicalId":9501,"journal":{"name":"Bulletin of the Chemical Society of Ethiopia","volume":" ","pages":""},"PeriodicalIF":1.2,"publicationDate":"2023-05-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42352167","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}
ABSTRACT. Complexes of Co(II), Ni(II) and Cu(II) ions with tetra amine hydrazide ligand [H4L] were prepared and characterized using physical and spectral methods. Analytical data showed that the complexes found in (1:2) ligand:metal ratio. Spectral studies revealed that the ligand bonded to the metal ion in neutral tetradentate or tetrabasic tetradentate manner through azomethine nitrogen atom, protonated/deprotonated hydroxyl group. From the electronic spectral data together with magnetic susceptibility values a distorted octahedral structure can be proposed for all complexes except complex 2 which has square planar structure. Electron spin resonance spectra for Co(II) complex 6 revealed axial symmetry with g|| > g⊥ > ge, indicating distorted octahedral or square planar structures and the unpaired electron exists in a d(x2−y2) orbital with marked covalent bond feature. Quantum chemical calculations have been performed to study structures and energetics of the ligand and its complexes. The prepared complexes showed good to excellent antimicrobial activity, and the most active complexes against Aspergillus niger were 3 with zone of inhibition of 23 mm. Complex 7 showed interesting activity against Escherichia coli with zone of inhibition of 23 mm. KEY WORDS: Metal complexes, Nitrogen moiety, Antimicrobicide activity Bull. Chem. Soc. Ethiop. 2023, 37(4), 901-915. DOI: https://dx.doi.org/10.4314/bcse.v37i4.8
{"title":"Binuclear transition metal complexes containing 6 N moieties Schiff base ligand: Synthesis, characterization and microbicide activities","authors":"Sabreen Mohamed Elgamasy, Samar Ebrahim Abd-ElRazek","doi":"10.4314/bcse.v37i4.8","DOIUrl":"https://doi.org/10.4314/bcse.v37i4.8","url":null,"abstract":"ABSTRACT. Complexes of Co(II), Ni(II) and Cu(II) ions with tetra amine hydrazide ligand [H4L] were prepared and characterized using physical and spectral methods. Analytical data showed that the complexes found in (1:2) ligand:metal ratio. Spectral studies revealed that the ligand bonded to the metal ion in neutral tetradentate or tetrabasic tetradentate manner through azomethine nitrogen atom, protonated/deprotonated hydroxyl group. From the electronic spectral data together with magnetic susceptibility values a distorted octahedral structure can be proposed for all complexes except complex 2 which has square planar structure. Electron spin resonance spectra for Co(II) complex 6 revealed axial symmetry with g|| > g⊥ > ge, indicating distorted octahedral or square planar structures and the unpaired electron exists in a d(x2−y2) orbital with marked covalent bond feature. Quantum chemical calculations have been performed to study structures and energetics of the ligand and its complexes. The prepared complexes showed good to excellent antimicrobial activity, and the most active complexes against Aspergillus niger were 3 with zone of inhibition of 23 mm. Complex 7 showed interesting activity against Escherichia coli with zone of inhibition of 23 mm. \u0000 \u0000KEY WORDS: Metal complexes, Nitrogen moiety, Antimicrobicide activity \u0000 \u0000Bull. Chem. Soc. Ethiop. 2023, 37(4), 901-915. \u0000DOI: https://dx.doi.org/10.4314/bcse.v37i4.8","PeriodicalId":9501,"journal":{"name":"Bulletin of the Chemical Society of Ethiopia","volume":" ","pages":""},"PeriodicalIF":1.2,"publicationDate":"2023-05-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42943163","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}
Emi Norzehan Mohamad Mahbob, Mohamad Syahrizal Ahmad, Illyas Md Isa, N. Hashim, A. ul-Hamid, Mohamad Idris Saidin, Suyanta M. Si
ABSTRACT. This work explicates a simple, rapid, and sensitive method for the electrochemical detection of dopamine (DOP) utilising 1-phenyl-3-methyl-4-orthofluorobenzoyl-5-pyrazolone (HPMoFBP)/multiwalled carbon nanotube (MWCNT) carbon paste electrode (CPE). The electrochemical behaviour of DOP was performed through cyclic voltammetry and square wave voltammetry. HPMoFBP/MWCNT showed a higher current at the lower potential for the oxidation of DOP compared to bare MWCNT. The sensor's improved electrocatalytic activity was observed to detect in a 1.0 x 10-1 M phosphate buffer saline (PBS) solution at pH 8.0. A good linear regression analysis was observed between electrical response and the concentration of DOP in the range of 1 to 1000 µM. Under optimized experimental conditions, 1.0 x 10-7 M has been determined as the limit of detection (LOD). The sensor has expressed considerable sensitivity towards DOP detection without interference and is successfully used to determine DOP in dopamine hydrochloride injection. KEY WORDS: Electrochemical sensor, Dopamine, Pyrazolone, MWCNT, Voltammetry Bull. Chem. Soc. Ethiop. 2023, 37(4), 845-857. DOI: https://dx.doi.org/10.4314/bcse.v37i4.4
摘要。本文阐述了一种利用1-苯基-3-甲基-4-邻氟苯甲酰基-5-吡唑啉酮（HPMoFBP）/多壁碳纳米管（MWCNT）碳糊电极（CPE）电化学检测多巴胺（DOP）的简单、快速、灵敏的方法。通过循环伏安法和方波伏安法研究了DOP的电化学行为。与裸MWCNT相比，HPMoFBP/MWCNT在DOP氧化的较低电势下显示出较高的电流。在pH 8.0的1.0 x 10-1M磷酸盐缓冲盐水（PBS）溶液中检测到传感器改进的电催化活性。在1至1000µM范围内的电响应和DOP浓度之间观察到良好的线性回归分析。在优化的实验条件下，确定1.0×10-7M为检测限（LOD）。该传感器在没有干扰的情况下对DOP检测表现出相当高的灵敏度，并成功用于测定盐酸多巴胺注射液中的DOP。关键词：电化学传感器，多巴胺，吡唑酮，MWCNT，伏安法。化学。Soc.Ethiop。2023,37（4），845-857.DOI:https://dx.doi.org/10.4314/bcse.v37i4.4
{"title":"Electrochemical sensor of multiwalled carbon nanotube electrode modified by 1-phenyl-3-methyl-4-orthofluoro benzoyl-5-pyrazolone for sensing dopamine","authors":"Emi Norzehan Mohamad Mahbob, Mohamad Syahrizal Ahmad, Illyas Md Isa, N. Hashim, A. ul-Hamid, Mohamad Idris Saidin, Suyanta M. Si","doi":"10.4314/bcse.v37i4.4","DOIUrl":"https://doi.org/10.4314/bcse.v37i4.4","url":null,"abstract":"ABSTRACT. This work explicates a simple, rapid, and sensitive method for the electrochemical detection of dopamine (DOP) utilising 1-phenyl-3-methyl-4-orthofluorobenzoyl-5-pyrazolone (HPMoFBP)/multiwalled carbon nanotube (MWCNT) carbon paste electrode (CPE). The electrochemical behaviour of DOP was performed through cyclic voltammetry and square wave voltammetry. HPMoFBP/MWCNT showed a higher current at the lower potential for the oxidation of DOP compared to bare MWCNT. The sensor's improved electrocatalytic activity was observed to detect in a 1.0 x 10-1 M phosphate buffer saline (PBS) solution at pH 8.0. A good linear regression analysis was observed between electrical response and the concentration of DOP in the range of 1 to 1000 µM. Under optimized experimental conditions, 1.0 x 10-7 M has been determined as the limit of detection (LOD). The sensor has expressed considerable sensitivity towards DOP detection without interference and is successfully used to determine DOP in dopamine hydrochloride injection. \u0000 \u0000KEY WORDS: Electrochemical sensor, Dopamine, Pyrazolone, MWCNT, Voltammetry \u0000Bull. Chem. Soc. Ethiop. 2023, 37(4), 845-857. \u0000DOI: https://dx.doi.org/10.4314/bcse.v37i4.4","PeriodicalId":9501,"journal":{"name":"Bulletin of the Chemical Society of Ethiopia","volume":"1 1","pages":""},"PeriodicalIF":1.2,"publicationDate":"2023-05-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41441105","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}
ABSTRACT. A mixed-ligand zinc(II) complex, [Zn(Hpma)(phen)Cl] (where Hpma– = N-(2,6-dimethylphenyl)oxamate and phen = 1,10-phenanthroline), has been prepared by the reaction of zinc chloride, ethyl (2,6-dimethylphenylcarbamoyl)formate (Hdmp) and 1,10-phenanthroline under basic conditions in dimethylformamide. The structure of the complex was characterised by elemental analysis, IR, 1H-NMR, UV-Vis absorption and X-ray crystallography. The metal complex crystallises in the monoclinic system (space group P21/c) and is composed of the five-coordinate zinc ion in a distorted spherical square pyramidal geometry. Stabilisation of single crystals occurs through hydrogen bonds and π-π stacking interactions. KEY WORDS: Zinc(II), N-(2,6-Dimethylphenyl)oxamate, 1,10-Phenanthroline, Crystal structure, Hydrogen bonding, π-π Stacking, Mixed-ligand Bull. Chem. Soc. Ethiop. 2023, 37(4), 891-900. DOI: https://dx.doi.org/10.4314/bcse.v37i4.7
{"title":"Synthesis and crystal structure of a mixed-ligand zinc(II) complex derived from ethyl (2,6-dimethylphenylcarbamoyl) formate and 1,10-phenanthroline","authors":"Tatenda Madanhire, B. van Brecht, A. Abrahams","doi":"10.4314/bcse.v37i4.7","DOIUrl":"https://doi.org/10.4314/bcse.v37i4.7","url":null,"abstract":"ABSTRACT. A mixed-ligand zinc(II) complex, [Zn(Hpma)(phen)Cl] (where Hpma– = N-(2,6-dimethylphenyl)oxamate and phen = 1,10-phenanthroline), has been prepared by the reaction of zinc chloride, ethyl (2,6-dimethylphenylcarbamoyl)formate (Hdmp) and 1,10-phenanthroline under basic conditions in dimethylformamide. The structure of the complex was characterised by elemental analysis, IR, 1H-NMR, UV-Vis absorption and X-ray crystallography. The metal complex crystallises in the monoclinic system (space group P21/c) and is composed of the five-coordinate zinc ion in a distorted spherical square pyramidal geometry. Stabilisation of single crystals occurs through hydrogen bonds and π-π stacking interactions. \u0000 \u0000KEY WORDS: Zinc(II), N-(2,6-Dimethylphenyl)oxamate, 1,10-Phenanthroline, Crystal structure, Hydrogen bonding, π-π Stacking, Mixed-ligand \u0000Bull. Chem. Soc. Ethiop. 2023, 37(4), 891-900. \u0000DOI: https://dx.doi.org/10.4314/bcse.v37i4.7","PeriodicalId":9501,"journal":{"name":"Bulletin of the Chemical Society of Ethiopia","volume":" ","pages":""},"PeriodicalIF":1.2,"publicationDate":"2023-05-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44176973","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}
Dashty Khasraw Ali, Nabil Adil Fakhre, Chnar Mohameed Rasheed
ABSTRACT. Two simple precise and accurate spectrophotometric techniques are developed for simultaneous determination of ternary mixture of urea, creatinine, and uric acid in humane urine sample. The first technique is a ratio derivative zero - crossing where measured urea at 216.61 nm, creatinine at 260.56 nm, and uric acid at 283 nm. The second technique is a successive derivative of ratio spectra where urea, creatinine, and uric acid measured at 203 nm, 261 nm, and 283 nm, 287 nm, respectively. These procedures do not need separation. The proposed methods showed excellent linear range over the concentration ranges of 1.0–15.0 μg/mL, 1.0–16.0 μg/mL, and 2.0–15.0 μg/mL for urea, creatinine, and uric acid, respectively. The recoveries ranged from 97.10% to 101.9% for urea, 97.22% to102.70 % for creatinine, and 97.45% to102.55 % for uric acid with relative standard deviations less than 1.56% for urea, 3.87% for creatinine, and 3.71% for uric acid. The analytical eco-scale and green analytical procedure index tools were used to evaluate how the proposed procedures will affect the environment. The simultaneous quantification of urea, creatinine, and uric acid in human urine samples can be accomplished with remarkable effectiveness by using the suggested approaches. KEY WORDS: Urea, Creatinine, Uric acid, Derivative spectrophotometry Bull. Chem. Soc. Ethiop. 2023, 37(4), 817-829. DOI: https://dx.doi.org/10.4314/bcse.v37i4.2
{"title":"Ratio derivative-zero crossing and successive derivative of ratio spectra for simultaneous determination of urea, creatinine, and uric acid in human urine samples","authors":"Dashty Khasraw Ali, Nabil Adil Fakhre, Chnar Mohameed Rasheed","doi":"10.4314/bcse.v37i4.2","DOIUrl":"https://doi.org/10.4314/bcse.v37i4.2","url":null,"abstract":"ABSTRACT. Two simple precise and accurate spectrophotometric techniques are developed for simultaneous determination of ternary mixture of urea, creatinine, and uric acid in humane urine sample. The first technique is a ratio derivative zero - crossing where measured urea at 216.61 nm, creatinine at 260.56 nm, and uric acid at 283 nm. The second technique is a successive derivative of ratio spectra where urea, creatinine, and uric acid measured at 203 nm, 261 nm, and 283 nm, 287 nm, respectively. These procedures do not need separation. The proposed methods showed excellent linear range over the concentration ranges of 1.0–15.0 μg/mL, 1.0–16.0 μg/mL, and 2.0–15.0 μg/mL for urea, creatinine, and uric acid, respectively. The recoveries ranged from 97.10% to 101.9% for urea, 97.22% to102.70 % for creatinine, and 97.45% to102.55 % for uric acid with relative standard deviations less than 1.56% for urea, 3.87% for creatinine, and 3.71% for uric acid. The analytical eco-scale and green analytical procedure index tools were used to evaluate how the proposed procedures will affect the environment. The simultaneous quantification of urea, creatinine, and uric acid in human urine samples can be accomplished with remarkable effectiveness by using the suggested approaches. \u0000 \u0000KEY WORDS: Urea, Creatinine, Uric acid, Derivative spectrophotometry \u0000Bull. Chem. Soc. Ethiop. 2023, 37(4), 817-829. \u0000DOI: https://dx.doi.org/10.4314/bcse.v37i4.2","PeriodicalId":9501,"journal":{"name":"Bulletin of the Chemical Society of Ethiopia","volume":" ","pages":""},"PeriodicalIF":1.2,"publicationDate":"2023-05-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41944622","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}
ABSTRACT. Inclusion complex between 3-amino-1,2,4-triazole picrate and β-cyclodextrin was synthesized in order to increase the picrate solubility. The complex was obtained by co-precipitation method and its stoichiometry is 1:1 (guest–host). The structure of picrate and complex has been established by UV, X-ray diffractometry powder spectra, TGA, DSC, IR, 1H NMR, and 13C NMR. The influence of the effect of pH on the complexation has been discussed. The value of apparent formation constant is 1.2 x 104. KEY WORDS: Amino triazole, Picrate, Inclusion complex, pH Bull. Chem. Soc. Ethiop. 2023, 37(4), 973-982. DOI: https://dx.doi.org/10.4314/bcse.v37i4.13
{"title":"Synthesis and characterization of inclusion complex of -cyclodextrin and triazole picrate","authors":"S. Hichri, N. Matoussi, R. Abderrahim","doi":"10.4314/bcse.v37i4.13","DOIUrl":"https://doi.org/10.4314/bcse.v37i4.13","url":null,"abstract":"ABSTRACT. Inclusion complex between 3-amino-1,2,4-triazole picrate and β-cyclodextrin was synthesized in order to increase the picrate solubility. The complex was obtained by co-precipitation method and its stoichiometry is 1:1 (guest–host). The structure of picrate and complex has been established by UV, X-ray diffractometry powder spectra, TGA, DSC, IR, 1H NMR, and 13C NMR. The influence of the effect of pH on the complexation has been discussed. The value of apparent formation constant is 1.2 x 104. \u0000 \u0000KEY WORDS: Amino triazole, Picrate, Inclusion complex, pH \u0000Bull. Chem. Soc. Ethiop. 2023, 37(4), 973-982. \u0000DOI: https://dx.doi.org/10.4314/bcse.v37i4.13 ","PeriodicalId":9501,"journal":{"name":"Bulletin of the Chemical Society of Ethiopia","volume":" ","pages":""},"PeriodicalIF":1.2,"publicationDate":"2023-05-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47504590","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}
Yasmin Abdurahman, Deribachew Bekana, A. Temesgen, N. Bussa, Minbale Aschale, E. Teju, M. Amde
ABSTRACT. Quantification of engineered nanomaterials in the environment has attracted researchers’ interest recently because of their increased release to the environment. In this study, a recyclable and easily accessible magnetized coffee residue (MCR) is proposed for magnetic solid-phase extraction (MSPE) of zinc oxide nanoparticles (ZnO-NPs) from water samples. The MCR was synthesized using a simple one-step chemical co-precipitation method from coffee residue and was characterized by state-of-the-art techniques. Various parameters affecting the MSPE efficiency of ZnO-NPs were optimized and 8.5 pH, 75 mg adsorbent, 120 min extraction time, 10 mL sample volume, 4 mL of 0.001 M HCl as an eluting solvent, and 30 min elution time were identified as the optimum conditions. Under these conditions, the method showed excellent linearity (R2 = 0.995) and good sensitivity (detection limit, 0.12 mg L-1, and quantification limit, 0.4 mg L-1). Intra and inter-day percent standard deviations were 1.4 and 2.2%, respectively, for the analysis of 6 mg L-1 ZnO-NPs. The practical applicability of the method for the extraction of ZnO-NPs in environmental samples was evaluated, and recovery values in the range of 93.0–98.2% were obtained, confirming its successful performance. Generally, the technique is easy, economical, and eco-friendly that can be considered for the extraction of metal oxide nanoparticles. KEY WORDS: Zinc oxide nanoparticles, Magnetic coffee residue, Magnetic solid-phase extraction, Flame atomic absorption spectroscopy, Environmental waters Bull. Chem. Soc. Ethiop. 2023, 37(4), 859-873. DOI: https://dx.doi.org/10.4314/bcse.v37i4.5
{"title":"Magnetic coffee residue biosorbent for selective extraction of zinc oxide nanoparticles in water samples","authors":"Yasmin Abdurahman, Deribachew Bekana, A. Temesgen, N. Bussa, Minbale Aschale, E. Teju, M. Amde","doi":"10.4314/bcse.v37i4.5","DOIUrl":"https://doi.org/10.4314/bcse.v37i4.5","url":null,"abstract":"ABSTRACT. Quantification of engineered nanomaterials in the environment has attracted researchers’ interest recently because of their increased release to the environment. In this study, a recyclable and easily accessible magnetized coffee residue (MCR) is proposed for magnetic solid-phase extraction (MSPE) of zinc oxide nanoparticles (ZnO-NPs) from water samples. The MCR was synthesized using a simple one-step chemical co-precipitation method from coffee residue and was characterized by state-of-the-art techniques. Various parameters affecting the MSPE efficiency of ZnO-NPs were optimized and 8.5 pH, 75 mg adsorbent, 120 min extraction time, 10 mL sample volume, 4 mL of 0.001 M HCl as an eluting solvent, and 30 min elution time were identified as the optimum conditions. Under these conditions, the method showed excellent linearity (R2 = 0.995) and good sensitivity (detection limit, 0.12 mg L-1, and quantification limit, 0.4 mg L-1). Intra and inter-day percent standard deviations were 1.4 and 2.2%, respectively, for the analysis of 6 mg L-1 ZnO-NPs. The practical applicability of the method for the extraction of ZnO-NPs in environmental samples was evaluated, and recovery values in the range of 93.0–98.2% were obtained, confirming its successful performance. Generally, the technique is easy, economical, and eco-friendly that can be considered for the extraction of metal oxide nanoparticles. \u0000 \u0000KEY WORDS: Zinc oxide nanoparticles, Magnetic coffee residue, Magnetic solid-phase extraction, Flame atomic absorption spectroscopy, Environmental waters \u0000 \u0000Bull. Chem. Soc. Ethiop. 2023, 37(4), 859-873. \u0000DOI: https://dx.doi.org/10.4314/bcse.v37i4.5","PeriodicalId":9501,"journal":{"name":"Bulletin of the Chemical Society of Ethiopia","volume":" ","pages":""},"PeriodicalIF":1.2,"publicationDate":"2023-05-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44773256","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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