003210   GOKULNATH G, ANITHA P, MANIKANDAN R, UMARANI C (Chemistry Dep, Government Arts Coll, Salem - 636 007, Email: cuchem1966@gmail.com) : Synthesis, spectral characterization and biological evaluation of metal complexes of 2-thioxoquinoline aminophenol. Asian J Chem 2021, 33 (6), 1439 - 46.

A series of novel 2-thioxoquinoline aminophenol Schiff base based Co(II), Ni(II), Cu(II) and Zn(II) metal complexes [M(L)₂], (M = Co²⁺, Ni²⁺, Cu²⁺ & Zn²⁺; L = 2-thioxoquinoline aminophenol) were synthesized and characterized by elemental analysis and spectral studies (FT-IR, UV-Vis, 1 H NMR,ESR and ESI-Mass). All experimental results showed that in these metal complexes, the central metal atom was coordinated by oxygen, nitrogen and sulfur donor atoms of deprotonated Schiff base. Further, the ligand and its metal(II) complexes were screened against Gram-positive (Staphylococcus aureus), Gram-negative (Escherichia coli) bacteria and fungus (Candida albicans) strains. in vitro Anticancer activity of ligand and its metal(II) complexes were also screened against HeLa cells (Human cervical cancer cells).

6 illus, 2 tables, 42 ref

003209   VERMA R, SINGH N, CHAUDHURI P (Amity Univ, Noida - 201 313, Email: pchaudhuri@amity.edu) : Nanoparticles mediated protein stability in comparison with osmolytes: in vivo Approach. Asian J Chem 2021, 33 (6), 1433 - 8.

The native three-dimensional structure of protein is quite unstable under critical destabilizing conditions. In order to enhance the stability and activity for a proper folded environment of a protein, many stabilizing materials are added such as nanoparticles and osmolytes to an unfolded state of protein. Osmolytes are the important group of molecules which are engaged by the cell as an adaption in the severe conditions. In this communication, a comparative in vivo study is reported for imparting the status of stability and folding ability of zebrafish dihydrofolate reductase (zDHFR) protein with gold nanoparticles and various osmolytes (glycerol, glucose and betain). Present observations revealed that the interaction of gold nanoparticles (AuNPs) with bacteria at the cellular level helps in maintaining the stability of protein more effectively than osmolytes which could be used for many biological and pharmacological approaches although glycerol as an osmolyte also stabilizes the protein at a significant level.

8 illus, 24 ref

003208   MADURANGA H A K, WEERASINGHE W R H, ATTANAYAKE R N, SANTHIRASEGARAM S, SHEVKAR C D, KATE A S, WEERAKOON G, SAMANTHI K A U, KALIA K, PARANAGAMA P A (Chemistry Dep, Kelaniya Univ, Kelaniya, Sri Lanka, Email: priyani@kln.ac.lk) : Identification of novel bioactive compounds, neurosporalol 1 and 2 from an endolichenic fungus, neurospora ugadawe inhabited in the lichen host, graphis tsunodae zahlbr. from mangrove ecosystem in puttalam lagoon, Sri Lanka. Asian J Chem 2021, 33 (6), 1425 - 32.

Endolichenic fungi (ELF) have been recognized as a promising source of bioactive secondary metabolites. Sri Lanka, a biodiversity hotspot, harbours a remarkable diversity in mangrove ecosystems. In the present study, endolichenic fungi obtained from mangrove lichens of Puttalam lagoon were studied for their secondary metabolites. An endolichenic fungus, Neurospora ugadawe, isolated from the lichen host Graphis tsunodae Zahlbr. was identified up to the species level. Secondary metabolites of N. ugadawe were extracted into ethyl acetate and crude extract showed promising antioxidant and anti-inflammatory activities. Bioassay guided separation on silica gel column chromatography and preparative TLC were performed to isolate the bioactive pure compounds. Two novel bioactive pure compounds were identified as Neurosporalol 1 and Neurosporalol 2. Neurosporalol 1 showed the highest antioxidant activity compared with the positive control BHT. Further, this compound showed very low anti-inflammatory activity compared to that of the positive control aspirin. Neurosporalol 2 showed comparable antioxidant and moderate anti-inflammatory activities.

9 illus, 3 tables, 20 ref

003207   KUMAR S, SINGH N, ANAND H (Chemistry Dep, Kurukshetra Univ, Kurukshetra - 136 119, Email: suresh980980@gmail.com) : Ion-solvent interaction behaviour of lithium perchlorate in N,N-dimethylacetamide and its binary mixtures with 2-aminoethanol: FTIR vibrational and NMR spectroscopy study. Asian J Chem 2021, 33 (6), 1415 - 9.

FTIR vibrational spectra and NMR spectra were studied for different electrolytic concentrations of lithium perchlorate (LiClO₄) in pure N,N-dimethylacetamide (DMA) and its binary mixtures with 2-amino ethanol (AE) of the different salt concentration ranges from 0.25 to 1.0 M with a molar ratio of LiClO₄:AE:DMA (4:4:4). The ¹³C NMR and FTIR studies have been used to investigate the behaviour of O=C-N deformation vibration and change in chemical shift. Study revealed that the Li⁺ ions coordinate to the nitrogen atom of NH₄ ⁺ structure and O of the C=O group of DMA. The interaction between Li⁺ ions and solvent molecules was confirmed by the carbonyl stretch symmetric ring deformation bands in DMA. From both studies it was found that the intensity increases, band split and chemical shift values of C atom of C=O of amide group also change with the increase in the concentrations of LiClO₄ in binary mixtures of AE + DMA, indicating a strong coordination between Li⁺ ions and DMA.

2 illus, 1 tables, 35 ref

003206   SANGEETHA R, MADHESWARI D, PRIYA G, LAVANYA P (Chemistry Dep, Government Arts Coll for Women, Salem - 636 008, Email: sangeetchem85@gmail.com) : Double minerals ions Co-substituted nano-hydroxyapatite based biocomposite implant for biomedical applications. Asian J Chem 2021, 33 (6), 1409 - 14.

The biocomposite of cerium(III)-copper(II) minerals co-substituted hydroxyapatite (Ce-Cu-HA)/poly(methyl methacrylate) (PMMA) was developed using a process of solvent evaporation. The analysis of X-ray diffraction (XRD), Fourier transform infrared (FT-IR), scanning electron microscope-energy dispersive X-Ray spectroscopy (SEM-EDX) confirmed the formation of Ce-Cu-HA in the PMMA matrix. In addition, the fabricated biocomposite demonstrated high antibacterial activity on Escherichia coli, which might be attributed to the action of Ce³⁺ and Cu²⁺ ions release on the substrate that blocks the cell transport pathways contributing to apoptosis. Biocomposites have been tested in osteoblast-like cells for their biological properties (biocompatibilty, alkaline phosphatase (ALP) activity and calcium deposition). Based on the present findings, it was proposed that Ce-Cu-HA/PMMA biocomposite could be a possible therapeutic candidate for bone tissue regeneration.

6 illus, 27 ref

003205   AHER J, BHAGARE A, GAWARE M, LOKHANDE D, KARDEL A, DHAYAGUDE A, JADHAV V, MAHALE K (Chemistry Dep, M.V.P. Samaj’s K.K. Wagh Arts, Science and Commerce Coll, Nashik - 422 209, Email: arunbhagare@gmail.com) : Concentration and temperature dependence of the thermodynamic properties of novel biologically active 3-substituted schiff base of 4-Piperidyl N-(4-chlorophenyl)maleimide. Asian J Chem 2021, 33 (6), 1403 - 8.

In present work, the concentration and temperature dependence of the thermodynamic properties of 3-substituted Schiff base of 4-piperidyl N-(4-chlorophenyl)maleimide compound in 80% DMSO was estimated. Concentration (0.002-0.01 M) and temperature (298-313 K) dependent densitometric and viscometric measurement were employed to evaluate limiting molar volume (φ⁰_v ), semi-empirical parameter (Sv), Falkenhagen (A) and Jones-Dole (B) viscosity coefficient. The obtained results suggest the presence of weaker solute-solvent interactions and stronger solute-solute interactions. It was observed that these interactions strongly depend on the temperature of the system. Furthermore, the Gibbs free energy (∆G), enthalpy (∆H) and entropy (∆S) of the system were also evaluated. The negative values of ∆G and ∆H and positive values of ∆S indicating reaction was spontaneous and exothermic in nature.

2 illus, 4 tables, 24 ref

003204   VENKATESWARLU S, MURTY G N, SATYANARAYANA M, SIDDAIAH V (Laila Impex Research Centre, Vijayawada - 520 007, Email: drvsomepalli@gmail.com, somepalli01@rediffmail.com) : Design, synthesis and biological activities of dihydroaurones. Asian J Chem 2021, 33 (6), 1396 - 1402.

To widen aurones applicability in achromatic food and cosmetic applications, a series of dihydroaurones were designed to mimic natural aurones as well as synthetic aurones. Dihydroaurones have been synthesized from the corresponding aurones by hydrogenation. These dihydroaurones and their corresponding aurones were screened for antioxidant, anti-inflammatory and tyrosinase enzyme inhibitory activity. Synthesized dihydroaurones (3b-f) displayed superior antioxidant activity in superoxide free radical scavenging assay than the standard gallic acid. Dihydroaurones (3b-f) also exhibited significant tyrosinase enzyme inhibitory activity and two dihydroaurones (3h, 3j) showed promising 5-lipoxygenase inhibitory activity

1 illus, 4 tables, 36 ref

003197   RADHAKRISHNA D, SUNEETHA D, SHYAMALA P (Physical and Nuclear Chemistry & Chemical Oceanography Dep, Andhra Univ, Visakhapatnam - 530 003, Email: shyamalapulipaka06@gmail.com) : Cloud point extraction and spectrophotometric studies for the extraction of nigrosin and aniline blue dyes using mixed micelles of TBAB and Triton X-114. Asian J Chem 2021, 33 (6), 1351 - 6.

The extractions of two anionic dyes viz. nigrosin and aniline blue by cloud point extraction method using mixed micelles of tetrabutylammonium bromide (TBAB) and Triton X-114 were conducted. To get the greatest extraction efficiency, pH of the solution, surfactant concentration, concentration of electrolyte, equilibrium temperature and time were optimized. A linear calibration curve in the range of 0.567-9.07 mg/L (nigrosin) and 0.982-19.645 mg/L (aniline blue) was obtained. Limit of detection were found to be 2.45 ng/L and 2.008 ng/L for nigrosin and aniline blue dyes, respectively. Thermodynamic parameters were also calculated to establish the feasibility of the process. This method was then used to determine the dyes in tap and sea water samples. The extraction efficiency was explained in terms of dye surfactant interaction as shown by observed spectral changes between anionic dye and cationic surfactant followed by solubilization of the complex in non-ionic surfactant.

6 illus, 3 tables, 14 ref

003196   PULLETIKURTHI K V K M, KOTHA S S K C, DODDIPALLA R, RUMALLA C S, KALIYAPERUMAL M, KORUPOLU R B (Medicinal Chemistry Dep, G.V.K. Biosciences Pvt. Ltd, Hyderabad - 500 076, Email: pulletikurthikrishnamohan@gmail.com, srinumohan@yahoo.co.in) : Degradation studies of lacidipine: Identification, isolation and structural characterization of stress degradation products using LCMS, Mass mediated Prep-HPLC, NMR and HRMS. Asian J Chem 2021, 33 (6), 1341 - 50.

The stability of lacidipine drug under stress conditions and the identification of the degradation products, according to ICH guidelines Q1A (R2) were investigated in the hydrolytic and oxidative stress conditions. The drug degradation occurred under hydrolytic conditions like (acidic and basic) while it was stable in the oxidative condition. Three degradation products were formed under acidic condition and one degradation product was formed under basic condition, which was separated by using APMS (Auto Purification Mass Spectrometer) and gradient elution with C18 column. The four degradants have not been characterized earlier and in the present study all the structures were established and characterized using NMR spectroscopy (1D and 2D) and HRMS (high resolution mass spectrometer).

6 illus, 5 tables, 27 ref

003195   GOLOLO S S, SEMENYA C J, OLIVIER M T, SETHOGA L J, MATHE E H, MASEKO R B (Biochemistry Dep, Sefako Makgatho Health Sciences Univ, Pretoria, South Africa, Email: Stanley.gololo@smu.ac.za) : Metabolite profiling of different tissues of barleria dinteri through the GC-MS Analysis. Asian J Chem 2021, 33 (6), 1336 - 40.

Barleria dinteri is a medicinal plant with distribution in the Limpopo, Gauteng and Mpumalanga provinces of South Africa as well as in Botswana, Swaziland and Namibia with exclusive specific habitation on limestone-rich soil. The plant species is used by traditional healers for wound healing and treatment of some intestinal tumours, as well as to relieve joint pains and toothache. The present study was aimed at the metabolite profiling of the different tissues (branches, flowers, leaves, roots) of Barleria dinteri using GC-MS analysis. Different extracts of the plant parts samples were subjected to GC-MS analysis and detected compounds were compared for presence amongst the different tissues. The results of the study revealed that all different parts (branches, flowers, leaves and roots) of B. dinteri, possess compounds that are detectable through GC-MS analysis with most compounds detected in the aerial parts, particularly the flowers. The results of the current study could serve as a basis for the possible plant parts substitution of the roots of B. dinteri with the aerial parts and the exploration of the pharmacological properties of the flowers for sustainable uses of the plant species for medicinal purposes.

7 tables, 24 ref

003194   BHUKYA B, GUGULOTH H (Chemistry Dep, Kakatiya Univ, Warangal - 506 009, Email: hanmanthu.guguloth@yahoo.com) : Synthesis and anticancer activity of novel oxadiazole functionalized pyrazolo[3,4-b]pyridine derivatives. Asian J Chem 2021, 33 (6), 1331 - 5.

A series of novel oxadiazole functionalized pyrazolo[3,4-b]pyridine derivatives (6a-n) was synthesized using 6-thiophenyl-4- (trifluoromethyl)-1H-pyrazolo[3,4-b]pyridin-3-amine (1) through reaction with 2-bromoethyl acetate, followed by hydrazine hydrate to afford hydrazide derivatives (5). These compounds were further treated with aromatic acids in the presence of phosphoryl chloride and obtained oxadiazole functionalized pyrazolo[3,4-b]pyridine derivatives (6a-n). All the synthesized compounds 6a-n were screened for anticancer activity against four cancer cell lines such as HeLa - cervical cancer (CCL-2); COLO 205-colon cancer (CCL-222); HepG2-liver cancer (HB-8065); MCF7-breast cancer (HTB-22). Compounds 6i, 6m and 6n were found to have more prominent anticancer activity at micromolar concentration.

1 illus, 1 table, 25 ref

003193   YERRA S , BABU P K, SREENIVASULU B, SHARMA H K, NAIDU K M, RAO B V (Organic Chemistry Dep, AU Coll of Science and Technology, Visakhapatnam - 530 003, Email: ysr10633@gmail.com) : A Novel Reverse Phase HPLC method for the quantification of potential genotoxic impurities in doripenem monohydrate: A broad-spectrum carbapenem antibiotic drug. Asian J Chem 2021, 33 (6), 1325 - 30.

A novel sensitive gradient reverse phase high performance liquid chromatographic (RP-HPLC) method has been developed and validated for the quantification of potential genotoxic impurities in doripenem monohydrate (DORIBAX) drug substance, namely mono-p-nitrobenzyl malonate, 1β-methyl bicyclic ketoester, desilylated β-keto ester, 1β-methyldiazoazetidinone, deprotected doripenem side chain, N-protected mercapto alcohol, protected doripenem and doripenem side chain. The analysis performed on Alliance Waters e2695 separation module on C18 (250 × 4.6) mm, 5 µm (make: Inertsil) column, oven temperature maintained at 40 ºC and UV detection at 270 nm. The separation was accomplished using buffer (pH 6.0 ± 0.05) and acetonitrile in the ratio of 98:2 v/v as mobile phase-A and acetonitrile as mobile phase-B, flow rate: 1.0 mL/min and injection volume: 50 µL. The proposed method was validated as per ICH guidelines in terms of limit of detection (LOD), limit of quantification (LOQ), linearity, precision, accuracy and specificity.

3 illus, 5 tables, 10 ref

003192   KUNARTI E S, ROTO R, SUTARNO S, BUDI I S, MARDIANSYAH M (Chemistry Dep, Gadjah Mada Univ, Yogyakarta, Indonesia, Email: eko_kunarti@ugm.ac.id) : Effective photocatalytic degradation of nitrobenzene by magnetite modified titania composite. Asian J Chem 2021, 33 (6), 1319 - 24.

Magnetic photocatalyst of magnetite modified titania composite Fe₃O₄/TiO₂ was prepared by co-precipitation and sol-gel methods followed by calcination at 450 ºC. The produced material was confirmed by XRD, FTIR spectrophotometer, vibrating sample magnetometer and transmission electron microscope. The solid material was tested as a photocatalyst for degradation of nitrobenzene under UV light irradiation. The progress of degradation of nitrobenzene was monitored by using a UV-visible spectrophotometer. The photodegradation of nitrobenzene could be best realized at a medium pH of 7 and 120 min of irradiation. The reaction rate constant of nitrobenzene degradation catalyzed by TiO₂ and Fe₃O₄/TiO₂ solids were found to be 0.0058 min-1 and 0.0092 min-1, respectively. The photocatalyst was recoverable by use of a magnetic bar and reusable.

8 illus, 1 table, 31 ref

003191   SUMA S, SEEMA S, MANOJ S V, SUMI V S, RIJITH S (Chemistry Dep, Sree Narayana Coll, Kollam - 691 001, Email: rijithsreenivas@gmail.com) : Synthesis and evaluation of Fe(III) Embedded silane grafted layered double hydroxide with reduced graphene oxide support as an efficient adsorbent for V(V) and Se(IV) from aqueous systems. Asian J Chem 2021, 33 (6), 1309 - 18.

The objectives of present work emphasize the successful usage of Fe(III) modified layered double hydroxide clays with reduced graphene support (Si-rGO/LDH-Fe) for the removal of V(V) and Se(IV) from aqueous systems. The precursors along with the modified and sorbent loaded materials were successfully characterized by BET surface area analyzer, SEM-EDS mapping, FTIR, potentiometric titrations and XPS analysis. Sorption performance of Si-rGO/LDH-Fe towards V(V) and Se(IV) under optimized conditions such as pH, temperature and concentration were investigated. The equilibrium and kinetic investigations revealed that the adsorption of V(V) and Se(IV) onto SirGO/LDH-Fe follows non-linear Langmuir isotherm and pseudo-second-order model, respectively. The equilibrium reached within 120 min and the Langmuir isotherm fit well with the experimental data. The adsorption mechanism was proposed to be ligand exchange with electrostatic interactions. Such results indicated that V(V) and Se(IV) species interact by the protonated hydroxyl moieties on the surface of Si-rGO/LDH-Fe. The practical efficacy and effectiveness of Si-rGO/LDH-Fe was also compared with some of the related works reported so far. The regeneration capacity and reusability of Si-rGO/LDH-Fe were also tested by employing four cycles of desorption experiments.

8 illus, 3 tables, 43 ref

003190   MONDAL D, MAHATA D, HANSDA K M, MONDAL S, DAS A (Chemistry Dep, Sidho-Kanho-Birsha Univ, Purulia - 723 104, Email: ajit873779@gmail.com, souravchemskbu@gmail.com) : Potential use of green synthesized Al₂O₃ (Alumina) nanoparticles from guava leaves (Psidium guajava) for the removal of methylene blue from wastewater. Asian J Chem 2021, 33 (6), 1304 - 8.

Recently non-harmful nanomaterials have acquired critical significant attention in wastewater treatment containing organic pollutants especially toxic and hazardous dyes. In this regard, a low cost and eco friendly method has been investigated for the green synthesis of alumina nanoparticles (Al₂O₃ NPs). The alumina nanoparticles were synthesized using an aqueous extract of Psidium guajava leaf as a potential stabilizing agent. The UV-visible spectroscopy, Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM) and energy-dispersive spectroscopy (EDS) techniques were used to characterize the synthesized nanoparticles. The absorption at 281 nm confirmed the formation of alumina nanoparticles. The FTIR spectra and XRD analysis confirmed the presence of various functional groups and crystalline structures of Al₂O₃ NPs during the synthesis. The spectrum clearly indicates the organic moieties in Psidium guajava extract are responsible for the biosynthesis of Al₂O₃ NPs. The suface morphology of Al₂O₃ NPs was confirmed by SEM and EDS studies. Besides this, the removal of methylene blue through adsorption and kinetic study was also reported.

9 illus, 3 tables, 33 ref

003189   KAUR M, BHATIA S K, SINGH B (Chemistry Dep, DAV Coll, Jalandhar - 144 008, Email: manpreet21044@gmail.com) : One-Pot solvent free, green route to novel substituted spiro[oxindole-isoxazolidine] Derivatives: Novel candidates as antimicrobial agents. Asian J Chem 2021, 33 (6), 1299 - 1303.

The environmentally benign catalyst and solvent-free synthesis of ketonitrones may not always be accomplished by simple condensation reactions. The occasional reports of green synthetic routes toward these compounds have been reported. The key features of this 1,3- dipolar cycloaddition reactions of N-[4-(-carboxycyclohexylmethyl)]maleimide with substituted isatin ketonitrone under microwave conditions resulted in the green synthesis of series of novel fluoro-substituted spiro[oxindole-isoxazolidine] derivatives in high yields, improved purity and short reaction times. All the synthesized compounds have been identified as potent in vitro antimicrobial agents. These results promoted the greener route to synthesize spiro[oxindole-isoxazolidine] derivatives with immense pharmacological importance in eco-friendly manner

6 illus, 21 ref

003188   RAJA R, VENIS A R, SELVAN R T, MOHANDAS T (Chemistry Dep, St. Joseph’s Coll, Tiruchirappalli - 620 002, Email: rajarampraveen85@gmail.com) : Decolourization of congo red dye using solar/H₂O₂ Process. Asian J Chem 2021, 33 (6), 1294 - 8.

The Congo red dye was decolourized by advanced oxidation process using solar/H₂O₂ method and the effect of various parameters on decolourization like pH, H₂O₂ concentration, dye concentration, solar light intensity, additives, COD and TOC removal studies and kinetic studies were investigated. The photodegradation process was done by exposing dye solutions with the concentration of 100 mg/L treated with 50% H₂O₂ to sunlight with the lux intensity range of 60,000-90,000 lux. The best possible pH 2 with an optimal H₂O₂ concentration of 1000 mM to achieve 100% decolourization within the period of 5 h. The kinetic studies done on H₂O₂ concentration also proved that the high solar light intensity leads to higher decolourization and low solar light intensity leads to lesser decolourization. Addition of additives like H₂PO₄ – and Cl– leads to a decrease in the rate of decolourization. The removal of COD and TOC removal was found to be 83.26% and 5.18%, respectively.

7 illus, 17 ref

003187   KUMARI K, MAKEN S (Chemistry Dep, Deenbandhu Chhotu Ram Univ of Science and Technology, Murthal - 131 039, Email: sanjeevmakin@gmail.com) : Optical properties, excess volume prediction from refractive index and intermolecular interactions in Dibutylamine + Isomeric Butanol. Asian J Chem 2021, 33 (6), 1287 - 93.

The alkyl or alkanol amines are widely used as absorbent for CO₂ capture owing to interaction between amines and CO₂. In order to increase the CO₂ loading in amine based absorbents, blending of amine with alkanol may be one option. As thermophysical properties of of utmost importance in designing, in present work, the refractive index of dibutylamine (DBA) and isomeric butanol as well as their binary mixtures at 298.15 K to 308.15 K were measured. The ∆n are found positive for DBA + isomeric butanol mixtures. The ∆n values were correlated with Redlich-Kister polynomial. The refractive index data were also predicted by various correlations and results were expressed in terms of standard deviation. The ∆n values were also employed to calculate the excess molar volume of the present binary mixtures. Further ∆n data analysed in terms of intermolecular interaction among DBA (1) + isomeric butanol (2) mixtures.

4 illus, 4 tables , 47 ref

003186   CHOWDHURY H, BERA R, ADHIKARY C (Education Dep, The Univ of Burdwan, Golapbag, Burdwan - 713 104, Email: cadhikary@edu.buruniv.ac.in) : Synthesis, structure, magnetic and catalytic competency of a tetradentate (NNOO) schiff base mediated dimeric copper(II) complex. Asian J Chem 2021, 33 (3), 1280 - 6.

One dinuclear copper(II) complex {µ-[2,2′-{ethane-1,2-diylbis[(azanylylidene)methanylylidene]}bis(phenolato)]}-{µ-[2,2′-{ethane-1,2- diylbis[(azanylylidene)methanylylidene]}bis(phenolato)]}dicopper(II), [Cu₂(salen)²] (1) [salen2− = [2,2′-{ethane-1,2-diylbis- [(azanylylidene)methanylylidene]}bis(phenolato)] has been isolated and characterized by X-ray diffraction analysis and spectroscopic studies. X-ray single crystal structure examination revealed that each Cu(II) center in the asymmetric unit of 1 adopts a distorted square planar geometry with a CuN₂O₂ chromophore, where two asymmetric units are attached through congregation of Salen involving Cu-O bond to form dinuclear molecular unit [Cu2(salen)₂]. In crystalline state, these dinuclear entities in 1 are extended through C-H···π interactions and π···π interactions displaying a 3D network structure. The variable-temperature magnetic susceptibility measurement asserted a dominant antiferromagnetic interaction between the copper(II) centers through Cu-O-Cu linkage in 1 with J = -1.46 cm-1. The catalytic efficacy of complex 1 was studied in a series of solvents for the oxidation of styrene and cyclooctene using tert-butyl-hydroperoxide (TBHP) as an active oxidant under mild conditions. The catalytic reaction mixture has been analyzed by gas chromatography and it displayed that the yield of the epoxidation and its selectivity is optimum in acetonitrile medium.

7 illus, 8 tables, 37 ref

003185   SAHU A, SWAIN S S, PRADHAN D, SAHU D K, BISWASROY P, KAR B, RATH G, GHOSH G (Siksha 'O' Anusandhan, Bhubaneswar - 751 030, Email: goutamghosh@soa.ac.in) : Identification of bioactive compounds from alphonsea madraspatana leaves against multi drug resistance bacteria. Asian J Chem 2021, 33 (6), 1273 - 9.

In this study, the antimicrobial compounds present in leaves of Alphonsea madraspatana was identified by using RP-HPLC, LC/MS and GC/MS and found to be active against multiple drug resistant (MDR) bacteria e.g. Escherichia coli, Staphylococcus aureus and Pseudomonas aeruginosa. Extraction of dried plant leaves was performed by solvent gradient technique. Antimicrobial study was performed with each extract. n-Hexane and methanol extracts were further subjected to analysis for identification of potent antimicrobial compounds due to their better antimicrobial activity as compared to remaining extracts. The methanolic extract was more active than n-hexane extract. As nhexane extract contains non-polar compounds, it was subjected to GC-MS analysis and methanol extract was subjected to RP-HPLC followed by LC/MS due to presence of polar components. Among the isolated compounds, four compounds were identified as potent antimicrobial. RP-HPLC and LC/MS analysis of methanol extract also ensured the presence of four potent antimicrobial compounds as follows: (i) kaempferol-3-O-rotinoside-orhamnoside (m/z 748), (ii) 3-hydroxypropylglucosinolate (m/z 377), (iii) luteolin-7-O-glucoside (m/z 448) and (iv) genistein-7-O-glycoside (m/z 432). Leaves of this plant may be used as potent antibacterial agents due to presence of antimicrobial compounds.

2 illus, 6 tables, 42 ref

003184   RAMANA L V, RAO K M C A, RAO M S A, RAMANAIAH C V, RAO G N (Divi?s Laboratories Limited, Visakhapatnam - 531 162, Email: bnrao@divislabs.com) : Synthesis and biological activity of triazole derivatives of osajin. Asian J Chem 2021, 33 (6), 1267 - 72.

In the present study, osajin-1,2,3-triazole hybrids were designed, synthesized and evaluated for their anti-proliferative activity against MCF-7, PC-3 and Hela cell lines. Many of the synthesized hybrid derivatives were found potent than the parent compound, osajin (1). All the semi-synthesized derivatives (3a-j) were characterized by using mass and NMR spectroscopic techniques. Among the newly synthesized compounds, 3c, 3d, and 3e were shown promising activities against the tested cell lines compared with doxorubicin standard. In addition, molecular docking studies of the synthesized compounds have shown a good correlation with in silico molecular docking analysis by exhibiting strong interactions with the inhibitor HERA-protein.

1 illus, 2 tables, 16 ref

003183   GURAV S S, WAGHMODE K T, NIKAM B T (Chemistry Dep, D.G. Ruparel Coll, Mahim, Mumbai - 400 016, Email: shaileshguravudc@gmail.com) : Efficient and facile synthesis of benzimidazole induced schiff bases and their potent antibacterial activity and computational study. Asian J Chem 2021, 33 (6), 1261 - 6.

Synthesized benzimidazole induced Schiff base analogues were characterized by mass, ¹³C NMR, ¹H NMR and UV-visible spectroscopy. To get more information about binding mechanism, molecular docking studies were carried out and the obtained results concluded that the compounds could effectively bind with receptor. in vitro Antibacterial screening was carried out against four strains (S. aureus, B. subtilis, P. aeruginosa and E. coli) and exhibited good antibacterial activity. The gastrointestinal absorption (HIA) and brain penetration (BBB) was evaluated by The BOILED-Egg model, which showed that two compounds anticipated being effectively effluated by the Pglycoprotein from central nervous system after penetration and can accounts for brain access and passive gastrointestinal absorption. Computational screening showed 0.55 bioavailability score for all synthesized compounds.

4 illus, 4 tables, 30 ref

003182   GELAW T B, SAROJINI B K (Industrial Chemistry Dep, Mangalore Univ, Mangalagangothri - 574 199, Email: bksaroj35@gmail.com, tadesse.bassie892@gmail.com) : Enhancing the performance and recyclability of polyaniline/TiO₂ hybrid nanocomposite by immobilizing with zein/hydroxyethyl cellulose composites for removal of anionic dyes. Asian J Chem 2021, 33 (6), 1253 - 60.

Fabrication of a stable, recyclable and eco-friendly photocatalyst for dye treatment is vital in sustaining a clean ecosystem. In this regard, polyaniline/TiO₂ (PANI/TiO₂) photocatalyst was immobilized by zein/hydroxyethyl cellulose (zein/HEC) adhesive to enhance recyclability and catalytic activity. The blending of zein/HEC/PANI/TiO₂ photocatalyst involves in situ oxidative polymerization, followed by immobilization with zein/HEC functionalized composites. The PANI/TiO₂ composite was successfully grafted with the adhesive through physicochemical interaction, as evidenced by field emission scanning electron microscope (FESEM), Fourier transform infrared spectroscopy (FTIR) and powder X-ray diffractometer (XRD). The simultaneous thermal analysis (STA) results show that the photocatalyst has the best thermal stability relative to PANI and PANI/TiO₂ in the recommended range of dye degradation temperature. The effect of external factors like TiO₂ nanoparticle proportion, pH of the solution and catalyst dosage was studied in response to dye degradation capacity. The synthesized catalyst is efficient to degrade methyl orange in a wide range of pH. The kinetics of the catalysis reaction obeys the first order kinetics. The maximum degradation efficiency achieved was 97.9% and 84.3% in the presence and absence of light, respectively. The catalyst was easily recovered by decantation and its catalytic efficacy was more than 94% after 5 cycles. Hence, it is a promising alternative for decolourizing anionic dyes from wastewater.

9 illus, 1 table, 66 ref

003181   REDDY T P, DUSSA N, MAMIDI S, PANASA M, CHAVAKULA R, PADMA M (Chemical Research Dep, APL Research Centre-II, Sangareddy District - 502 329, Email: tpurendar@yahoo.co.in) : Identification, isolation and origin of potential dimer impurities of dichlorphenamide: A carbonic anhydrase inhibitor drug (antiglaucoma). Asian J Chem 2021, 33 (6), 1249 - 52.

Present work describes the identification, isolation and characterization of two new process related dimeric impurities of dichlorphenamide (1). During the synthesis of dichlorphenamide, the formation of two new dimeric impurities namely 2,3-dichloro-5-(3,4-dichloro-5- sulfamoyl-phenyl)sulfonyl-benzenesulfonamide (2) (1,1′-dichlorphenamide dimer) and 2,3-dichloro-5-(2,3-dichloro-5-sulfamoylphenyl)sulfonyl-benzenesulfonamide (3) (1,3′-dichlorphenamide dimer) was observed. In addition, origin and the strategies adapted to control these potential dimer impurities were also described. These impurities have a substantial impact on the quality of the drug substance as well as drug product.

19 ref

003180   HANSDA K M, MAHATO A, SINGH P, DAS A, MAHATA N (Chemistry Dep, Sidho-Kanho-Birsha Univ, Purulia - 723 104, Email: nagendranath_mahata.chem@skbu.ac.in) : Influence of reaction conditions in the selective hydrogenation of isophorone to 3,3,5-Trimethylcyclohexanone over NiC composite catalyst. Asian J Chem 2021, 33 (6), 1245 - 8.

NiC composite catalyst was synthesized by carbon deposition over skeletal Raney nickel by exploiting methane decomposition reaction and applied in the hydrogenation of isophorone. Nickel content in the composite catalyst was ascertained by atomic emission spectroscopy. Influence of operating variables (agitation, solvent, temperature, H₂ pressure and isophorone concentration) on the hydrogenation of isophorone over the NiC composite catalyst was investigated. Ethyl acetate was observed to be an excellent solvent for the reaction in terms of both isophorone conversion as well as 3,3,5-trimethylcyclohexanone selectivity. The catalytic reaction was observed to be 0.06 order with respect to isophorone and 0.82 order with respect to H₂.

5 illus, 3 tables, 15 ref

003179   KUMAR M, VERMA K K, GARG S (Chemistry Dep, Maharishi Dayanand Univ, Rohtak - 124 001, Email: sapanagarg1511@gmail.com) : Some Organotellurium(IV) complexes of 1-methyl-3-(p-tolylimino)indolin-2-one schiff base. Asian J Chem 2021, 33 (6), 1236 - 44.

Six new hexa-coordinated organotellurium(IV) complexes of type RTeCl₃·NMeIPT and R₂TeCl₂·NMeIPT (R = 4-hydroxyphenyl, 4- methoxyphenyl or 3-methy-4-hydroxyphenyl; NMeIPT(L) = Schiff base (1-methyl-3-(p-tolylimino)indolin-2-one) derived from condensation of 4-methylisatin and p-toluidine) have been synthesized and characterized by different spectral studies like elemental analyses, molar conductance, infrared, mass spectrometry, ¹ H NMR, ¹³C NMR and UV-visible spectroscopy. On the basis of spectroscopic data, it is evident that Schiff base behaves as NO donor bidentate ligand via azomethine nitrogen atom and oxygen atom from carbonyl group for all the tellurium(IV) complexes. The results showed that all the organotellurium(IV) complexes possess distorted octahedral geometry. Geometry of the all organotellurium(IV) complexes was optimized and their theoretical quantum mechanical parameters were calculated. This computational study also suggests octahedral geometry for complexes. The antimicrobial activity of NMeIPT and all the organotellurium(IV) complexes were screened against bacteria i.e. Xanthomonas campestris and Bacillus cereus and fungi i.e. Fusarium oxysporum, Candida albicans and Sclerotinia sclerotium.

5 illus, 8 tables, 46 ref

003178   TIWARI A K, ABRAR A, PREETI (Chemistry Dep, Deen Dayal Upadhyaya Gorakhpur Univ, Gorakhpur - 273 009, Email: dr_aktiwari@rediffmail.com) : Preparation and characterization of 18-crown-6 modified cellulose acetate membrane in uni-univalent aqueous electrolyte solutions. Asian J Chem 2021, 33 (6), 1229 - 35.

In present study, a cellulose acetate/18-crown-6 blend membrane (selective for K⁺ ions) was prepared by the solvent vapourization method. The surface morphology of the modified membrane was characterized by scanning electron microscopy (SEM) analysis, which indicate the smooth and homogeneous membrane surface. The effect of water and electrolyte (KCl and NaCl) concentration on the rate of water sorption and porosity was explained on the basis of physico-chemical parameters i.e. water content and water activity of the membrane phase. The variation of ionic transport number with respect to water activity, i.e. [dt^mK⁺ /da^m _w > dtmNa+ /dam w] has been observed in the present system. The transport of ions under concentration gradient in term of permeability, flow and flux was estimated by membrane/ solution conductance-time data. The variations of permeability, flux and flow values with respect to time for K⁺ and Na⁺ ions were found to be different. Membrane water activity (a^m _w) decreases with the increase of external electrolyte concentration. The effective fixed charge density of the membrane increases with increase of external electrolyte concentration. Permselectivity parameter of the membrane in both cases decline with increase of external electrolyte concentration.

8 illus, 2 tables, 17 ref

003177   SELVARANI R, BALASUBRAMANIYAN S, RAJASEKAR K, THAIRIYARAJA M, MEENAKSHI R (Chemistry Dep, Government Arts Coll, Ariyalur - 621 713, Email: selvasekar2008yoki@gmail.com) : Synthesis, DFT and bio-potential activities of Mn(II) and Hg(II) complexes with bidentate (E)-N′[(E)-3-Phenylallylidene]benzene-1,2-diamine. Asian J Chem 2021, 33 (6), 1222 - 8.

A new bidentate Schiff base (E)-N′[(E)-3-phenylallylidene]benzene-1,2-diamine derived from the condensation of o-phenylenediamine and cinnamaldehyde and its Mn(II) and Hg(II) complexes were synthesized and characterized by elemental analysis, molar conductance, magnetic moment, electronic spectra, IR, far-IR and NMR (¹ H & ¹³C) spectral studies. The elemental analysis and these metal proposed the metal:ligand stoichiometry and molecular formulae of the metal complexes. The molar conductance and electrochemical property indicates monomeric, neutral nature and redox properties of the metal complexes. The UV-visible spectral study supports the octahedral geometry for Mn(II) complex and square planar geometry for Hg(II) complex and further confirmed by magnetic moment. IR spectral data examined the coordination mode but far-IR is useful to identify the metal-ligand vibrations. The geometry, magnetic property and unsymmetrical nature of these metal complexes corroborated by NMR (¹ H & ¹³C) spectra. The DFT of Mn(II) complex studied and the structure optimized by B3LYP/Lan L2DZ using Gaussian 09W. Quantum chemical calculations were done by Mullikan population analysis, HOMO-LUMO and molecular electrostatic potential. The in vitro biological screening effects of the investigated complexes were tested against some bacteria and fungus by agar-well diffusion method. The results indicated that Mn(II) and Hg(II) complexes exhibit potentially active than the Schiff base which was further confirmed by pharmacokinetics study. The antioxidant activity of Schiff base and its Mn(II) complex was examined by radical scavenging DPPH method.

7 illus, 6 tables, 36 ref

003176   HO S M, NG S N, MUNAAIM M A (INTI International Univ, Malaysia, Email: soonmin.ho@newinti.edu.my) : Disposal method of crystalline silicon photovoltaic panels: A case studies in Malaysia. Asian J Chem 2021, 33 (6), 1215 - 21.

Previous studies have highlighted that fossil fuel accounted for the largest share of total energy consumption in worldwide if compared to renewable energy. However, it has many disadvantages such as emission of carbon dioxide gas, contributes to global warming, creates pollution, contributes to acid rain and unsafe. Nowadays, many solar power plants have been built in order to replace fossil fuel. Solar energy has bright future due to some advantages such as pollution free, cheap renewable energy, easy install solar cell panel and less maintenance. Solar photovoltaic development has remarkably grown since the early 2000s. Because an average panel lifetime is 30 years, 17,000 tonnes of solar panel wastes are anticipated in the year 2030 in Malaysia. As the solar photovoltaic market increases, so will the volume of decommissioned photovoltaic panels. Growing photovoltaic panel waste represents a new environmental challenge, but also miraculous opportunities to create value and pursue new solar photovoltaic end-of-life industries economic route.

4 illus, 10 tables, 38 ref

003175   SLAOUI M, GOUITAA N, LAHRICHI A, HARRACH A, HADDAD M, LAMCHARFI T (Sidi Mohammed Ben Abdellah Univ, Morocco, Email: lamcharfi_taj@yahoo.fr) : Synthesis and physico-chemical characterization of solid solution (1-x)CCTO−xPbTiO₃. Asian J Chem 2021, 33 (6), 1208 - 14.

The composite materials of (1-x)CaCu₃Ti₄O₁₂, xPbTiO₃((1-x)CCTO−xPT) were prepared by a modified solid-state method in several steps. The Rietveld refinement indicates the formation of the pure cubic and tetragonal phases for calcium copper titanate (CCTO) and leadtitanate (PT) pure ceramics, respectively. While for CCTO-PT composites, the coexistence of the two cubic and tetragonal phases was detected with the space group Im-3 and P4mm, respectively. The Raman spectra confirmed these phase formations. The SEM images indicated a change in grains shape from quadratic to semi-spherical with increases of PT contents and a reduce in average grains size with increase of PT content. The dielectric measurements as function of temperature showed two anomalies which exhibit a relaxation-like phenomenon and a clear diffuseness behaviour for all the samples. In addition, the conductivity of these materials decreases and the resistance of grain boundaries was found to increase with the increase of PT addition.

8 illus, 4 tables, 30 ref

003174   PINKI, SUBHASH, CHAUDHARY A (Chemistry Dep, Kurukshetra Univ, Kurukshetra - 136 119, Email: ashuchaudhary21@gmail.com, ashuchaudhary@kuk.ac.in) : Emerging potential of metallodrugs to target coronavirus: Efficacy, toxicity and their mechanism of action. Asian J Chem 2021, 33 (6), 1191 - 1207.

On eleventh March 2020, the contagion of the novel COVID-19 was announced by the WHO. Right now, there are no new enlisted medications that can viably cure the COVID-19 contagion. Some recently utilized drugs and combinations with their harmfulness profiles have been contemplated. The frequently announced poisonous impacts of these medicines, for example, hepatotoxicity, retinal harm, nephrotoxicity and cardiotoxicity. One of the most broadly examined drugs is favipiravir. The surface collaboration of favipiravir with organometallic composites came about by doping of transition metals of first row of the periodic table was analyzed to choose the most reasonable metallofullerenes for COVID-19 treatment. Some acknowledged pharmacophore edifices of bioactive constituents can be valuable in the explanation of against SARS-CoV-2 particulars. The advantage of utilizing arrangements encompassing phytochemicals is their sky-scraping wellbeing for ill persons and no negative reaction. Iron oxide nanoparticles (IONPs) were recently affirmed by the USFDA for anaemia therapy and variations have additionally exhibited its effectiveness against viruses in vitro for COVID-19. The adequacy of the Zn²⁺ salt enhancement could likewise be improved with Nigella sativa as its major bioactive segment would fill in as ionophore to permit Zn²⁺ to enter pneumocytes-the objective cell for the coronavirus (COVID-19). This review article depicts the utilization of medications, their usefulness and their harmful impacts for COVID-19 patients.

1 illus, 2 tables, 128 ref

003173   EMIN A (Lanzhou Univ, P.R. China, Email: adl19@lzu.edu.cn) : Progress in the applications of raman spectroscopy in microbial identification. Asian J Chem 2021, 33 (6), 1183 - 90.

After more than 40 years of development, surface-enhanced Raman spectroscopy (SERS) has become a powerful and mature analytical tool. It has been widely used in surface science, materials science, biomedicine, drug analysis, food safety, environmental testing, etc. SERS technology has molecular-level detection accuracy, which can effectively amplify signals and has obvious advantages in realizing trace substance detection. In present article, a comprehensive review of the SERS technology and related applications in microbial identification is carried out, and its future research hotspots and development directions are discussed.

6 illus, 72 ref

003172   KIM R P T, KHAN M N, LIEW S Y, AWANG K (Malaya Univ, Malaysia, Email: khalijah@um.edu.my) : Kinetic and mechanistic studies of acidic hydrolysis of goniothalamin. Asian J Chem 2021, 33 (5), 1176 - 82.

The acidic hydrolysis of goniothalamin was studied on the spectrophotometric kinetic study at different concentration of hydrochloric acid and temperature to determine the stability of the compound. Stability tests were performed using UV-VIS detection. This is a twostep reaction that involves formation of intermediate product. Rate constant of reactant forming intermediate product obeyed pseudo-firstorder kinetic, while the second step to form final product is independent on the concentration of HCl. The structure of final products was identified by NMR and MS. The acidic hydrolysis pathway was proposed to involve the opening of lactone ring, followed by dehydration and formation of a double bond.

6 illus, 4 tables, 14 ref

003171   UBAGARAMARY D, ENOCH I V M V, GUTTEDAR A, KUMAR R L, SULEBHAVI N (Chemistry Dep, M.V.J. Coll of Engineering, Bengaluru - 560 067, Email: ubagaramary.chemistry@gmail.com) : Thermo-physical properties of heterocyclic compounds with aliphatic alcohols at T = 303.15, 308.15 and 313.15 K. Asian J Chem 2021, 33 (5), 1169 - 75.

The densities (ρ), speeds of sound (u), and viscosities (η) have been measured for ternary liquid mixtures of tetrahydrofuran in cyclohexanone with 1-hexanol and 1-octanol at 303.15-313.15 K over the entire range of mole fractions and at atmospheric pressure 0.1 MPa. These experimental data have been used to estimate the thermophysical properties of heterocyclic compounds with aliphatic alcohols at T = 303.15, 308.15 and 313.15 K. Preliminary data was used to assess the excess free volume, internal pressure and free energy of Gibbs, which were discussed in light of the molecular interaction surviving in the mixtures. Analysis of each of the two contributions, namely interaction, free volume V^E showed that the contributions are positive for all systems. The variations of these parameters with the composition and the temperature were discussed with regard to the intermolecular interactions prevailing in these mixtures. These values also indicate the formation of a hydrogen bonding (C=O......OH) between the hydrogen atom of aliphatic alcohol of 1-hexanol/1-octanol and oxygen atom of heterocyclic compounds tetrahydrofuran in cyclohexanone in the ternary liquid mixtures.

4 illus, 8 tables, 42 ref

003170   REDDY C P, RAO G V, RAMAKRISHNA K, RAO K M V N (GVK Biosciences Pvt. Limited, Hyderabad - 500 076, Email: marutikmv@gmail.com) : Method development and validation for quantification of potential genotoxic impurity, PyCl in lansoprazole hydrochloride using liquid chromatography combined with mass spectrometry. Asian J Chem 2021, 33 (5), 1165 - 8.

A sensitive and robust high performance liquid chromatography combined with tandem mass spectrometry (LC-MS/MS) method was developed and validated for the determination of potential genotoxic impurity (PGI), 2-(chloromethyl)-3-methyl-4-(2,2,2-trifluoroethoxy)- pyridine hydrochloride (PyCl) in lansoprazole as per ICH Q2 guideline. In this method, PyCl and lansoprazole were well-separated from each other on Acquity UPLC BEH-C18 column (50 × 4.6 mm × 1.7 µ) in a gradient elution mode with the mobile phase consisting of 0.1% formic acid in water (mobile phase-A) and acetonitrile (mobile phase-B) at a flow rate of 0.4 mL/min. For the quantitation of Py-Cl, selective ion monitoring (SIM) mode was used with m/z 240 ion in LC-MS method. The validated method was found to be precise, accurate and linear from the range of LOQ level to 150% with respect to sample concentration and the correlation co-efficient was found to be 0.998. Limit of detection (LOD) and limit of quantifications (LOQ) were found to be 0.000012 and 0.000004 mg/mL, respectively. The validated method was found to be sensitive and the recoveries were found to be well within the range from 83.4% to 95.9% for Py-Cl. Further, the solution stability was also established as the same were found to be stable upto 24 h.

1 illus, 7 tables, 16 ref

003169   KAMRUZZAMAN1 , ALI R, KARIM R, CHOWDHURY S I, HASAN T (Chemistry Dep, Rajshahi Univ, Rajshahi - 6205, Bangladesh, Email: thasan.chem@ru.ac.bd) : Effect of flexible chain on mesomorphic properties of alkyloxy substituted 4-chloroazobenzene liquid crystals. Asian J Chem 2021, 33 (5), 1159 - 64.

Three rod-shaped alkyloxy substituted 4-chloroazobenzene liquid crystals, 1-(4-chlorophenyl)-2-[4-(alkyloxy)phenyl]diazene (hexayl, octyl and nonyl as flexible oxyalkyl chain) have been synthesized by diazotization of p-chloroaniline with phenol and subsequently performed etherification reaction with different alkyl bromides. The structures of the substituted 4-chloroazobenzene liquid crystals have been characterized by spectroscopic methods. The mesomorphic properties of the liquid crystals were examined by polarizing optical microscope (POM) and differential scanning calorimetry (DSC). All the oxyalkyl homologues of chloro substituted azobenzene showed enantiotropic smectic A (SmA) mesophase, which was understood clearly by the texture of the compounds employing polarizing optical microscope (POM) analysis. During heating scan in DSC analyses melting points, SmA-isotropic temperature and enthalphy changes associated with SmA-isotropic transition showed a remarkable impact on the spacer length of 4-chloro azobenzene derivatives.

4 illus, 1 table, 29 ref

003168   MANIVANNAN N, BALACHANDRAN V S, VASANTHA V S (Natural Products Chemistry Dep, Madurai Kamaraj Univ, Madurai - 625 021, Email: vasantham999@yahoo.co.in) : Carbon supported platinum-molybdenum alloy nanoparticles for oxygen reduction reaction. Asian J Chem 2021, 33 (5), 1153 - 8.

Fuel cells are gaining importance in the emerging area of power generation. However, sluggishness of the cathodic oxygen reduction reaction (ORR) and usage of expensive electrocatalysts are hindering its widespread application. Hence, an effort has been made in the present study to synthesize efficient electrocatalysts based on Pt-Mo alloys with varying atomic ratios (0-100 at. %) by thermal decomposition method. The synthesized samples were characterized using XRD, STEM, EDX and XPS techniques. The electrocatalytic activity for ORR was measured using cyclic voltammetry and rotating disk electrode for all the samples and Pt-Mo (1:1) electrocatalyst performed better among the synthesized electrocatalysts with ORR current density of 63 mA/cm² at an applied potential of 0.6 V vs. Hg/HgSO₄. The present study suggests that Pt-Mo studied are proven to be a superior catalyst than a costly Pt catalyst with high ORR activity

6 illus, 1 table, 28 ref

003167   SARMA P, MAHANTA P, BASUMATARY D, MEDHI C (Applied Sciences Dep, Gauhati Univ, Guwahati - 781 014, Email: debbasumatary@gmail.com, debbasumatary@gauhati.ac.in) : Manganese(IV) complexes derived from polyfunctional dihydrazone: Structural, electrochemical and antimicrobial studies. Asian J Chem 2021, 33 (5), 1144 - 52.

Manganese(IV) complexes viz. [Mn^IV(nagh)(A)₂]·2H₂O and [Mn^IV(nagh)(NN)] have been synthesized from ligand bis(2-hydroxy-1- naphthaldehyde)glutaryldihydrazone (naghH4) and auxiliary ligands, A = H₂O (1)/pyridine (2)/2-picoline (3)/3-picoline (4)/ 4-picoline (5) or NN = 2,2′-bipyridine (6)/1,10-phenanthroline (7). The elemental analysis, mass spectral and thermal studies supported the composition of all the manganese(IV) complexes. Structural aspects were determined from magnetic susceptibility, molar conductivity and spectral studies i.e. electronic, electron spin resonance and infrared. Their non-electrolytic nature were determined from molar conductances. Results from studies of magnetic moment, electronic and ESR suggested Mn(IV) ion in six-coordinate octahedral stereochemistry. The ligand coordinated to the metal in enolic form as a tetradentate in an anti-cis configuration as was correlated from IR data. Redox activities and antimicrobial potential against few Gram-positive and Gram-negative bacteria have been investigated for the dihydrazone and some manganese(IV) complexes.

4 illus, 6 tables, 34 ref

003166   ADENIRAN O I, MSOMI D B, OLIVIER M T, MOGALE M A (Biochemistry Dep, Sefako Makgatho Health Sciences Univ, South Africa, Email: seyefunmiadeniran@gmail.com) : Variation in anti-glycation and cross-link breaking effects of crude extracts of moringa oleifera leaf, seed and root. Asian J Chem 2021, 33 (5), 1137 - 43.

Study and comparing the anti-glycation and cross-link breaking effects of Moringa oleifera leaf, seed and root extracts with aminoguanidine, a known inhibitor of advanced glycation end-products (AGEs). Their phytochemical composition and extraction yields were also assessed. All seed and root extracts demonstrated significantly higher anti-glycation effect than aminoguanidine against total immunogenic AGEs (p < 0.05). Both seed and root polar (methanol and water) extracts exhibited significantly higher anti-glycation effect against N′-(carboxymethyl)lysine than aminoguanidine (p < 0.05). Polar extracts of all M. oleifera tested parts demonstrated higher anti-glycation activity against fluorescent AGEs than aminoguanidine (p < 0.05). With exception to the aqueous root extracts, all leaf, seed and root extracts of M. oleifera demonstrated an ability to break AGE-protein cross-links. The highest cross-link breaking effect was exhibited by ethyl acetate extract of leaves.The methanol extract of seeds of M. oleifera showed the presence of all tested secondary metabolites.

6 tables, 38 ref

003165   VISHNOI R K, BAJPAI S, CHATURVEDI D, SHUKLA M, KISHORE R, SRIVASTAVA N (Chemistry Dep, Amity Univ, Lucknow - 226 028, Email: devduttchaturvedi@gmail.com, sbajpai1@amity.edu) : Synthesis and antimicrobial activity of cyclic dithiocarbamates employing triton-B/CS₂ System. Asian J Chem 2021, 33 (5), 1133 - 6.

An efficient and green methodology to synthesize cyclic dithiocarbamates (compounds 1-11) was developed by reaction of primary amines, CS₂ and 1,2-dibromoethane or 1,4-dibromobutane, catalyzed by Triton-B (as PTC)/CS₂ system. Mass spectroscopy, elemental analysis and ¹ H NMR are used for characterization of the synthesized compounds (1-11). This effectual green tactics give good yield of product which entails mild conditions. Compounds (1-11) were found to possess in vitro antimicrobial activities against the pathogenic bacterial and fungal strain. The microbial strains used to screen activities are Escherichia coli, Staphylococcus aureus and Candida albicans.

2 tables, 49 ref

003164   BARAPATI S, RAGHASUDHA M, SOMAIAH P V (Chemistry Dep, Osmania Univ, Hyderabad - 500 007, Email: raghas13chem@nitw.ac.in vs_puppala@rediffmail.com) : Effect of Al doping on magnetic properties of Co-Mn nanoferrites synthesized via citrate-Gel method. Asian J Chem 2021, 33 (5), 1125 - 32.

The structural and magnetic properties of aluminium substituted Co-Mn nanoferrites synthesized via a chemical route viz. citrate-gel autocombustion method have been reported. Aluminium content has been varied from x=0 to x=1 with an increment of 0.2 in Co_0.75Mn_0.25AlxFe_2-xO₄. The structural confirmation was done with the basic characterization techniques such as XRD study, FTIR spectroscopic and the surface morphology was examined using SEM and EDX spectroscopic analysis. To study the optical absorption behaviour of the prepared ferrites, UV-visible spectral analysis was carried out. XRD analysis established the formation of cubic spinel structure of the materials with the average crystallite size of 15.5 nm to 19.94 nm. FTIR spectra has shown two absorption peaks that are characteristic of spinel nano ferrites. From the UV-visible spectral data, energy band gap (E_g) values were evaluated. The data witnessed an increase in the E_g value of the ferrite by doping of Al³⁺ ion into the ferrite. Room temperature magnetization measurements were carried out before and after aluminium doping in the samples using vibrating sample magnetometer. It was revealed that the substitution of aluminium in the lattice has modified the material into a soft magnetic material. Consequently, they find applications in transformer and motor cores.

10 illus, 4 tables, 37 ref

003163   SHAILESH S K, TIWARI B, YADAV K (Chemistry Dep, Lalit Narayan Mithila Univ, Darbhanga - 846 004, Email: skshailesh07@gmail.com) : Green synthesis, texture, electron diffraction, thermal and optical properties of cobalt doped arginine carbon nanotubes. Asian J Chem 2021, 33 (5), 1120 - 4.

In this work, a simple and viable method of green synthesis of multi-walled cobalt doped arginine carbon nanotubes (CNT’s) by chemical precipitation method using arginine amino acid is reported. The atomic force microscopy confirmed that metal ions present in a branched fashion on the surface of Co-doped arginine CNT’s and the obtained particle with diameter 20 nm well dispersed on the carbon nanotubes. The TEM analysis indicates the interlayer separation between the two adjacent carbon walls is estimated to be about 0.34 nm. The electron diffraction patterns indicate that the tube has nearly identical chirality for all of the concentric graphitic layers, as a zigzag-type MWCNT. The SEM analysis predicted tube like morphology and strain is existed on the surface of the CNTs. The Raman spectra confirmed the armchair (n = 8 to 11) multi-walled nanotubes with this chirality are assigned as a semiconducting type of nanotubes. The thermal property was studied by thermogravimetric analysis, differential thermal analysis and predicted the 27.81 % purity in CNTs.

5 illus, 31 ref

003161   MARGANAKOP S B, KAMBLE R R, NESARAGI A R, BAYANNAVAR P K, JOSHI S D, KATTIMANI P P, SUDHA B S (Studies in Chemistry Dep, Karnatak Univ, Dharwad - 580 003, Email: ravichem@kud.ac.in) : Microwave Assisted Synthesis of Quinoline Fused Benzodiazepines as Anxiolytic and Antimicrobial Agents. Asian J Chem 2021, 33 (5), 1107 - 14.

In the present study, an efficient, facile and green protocol for synthesis of quinoline fused 1,4-benzodiazepine (4a-j) by microwave irradiated condensation of 6/7/8-substituted 3-bromomethyl-2-chloro-quinoline (3a-j) obtained from 2-chloro 6/7/8-substituted quinoline3-carbaldehyde (1a-j) with 1, 2-phenylenediamine was developed. Surflex docking studies with K⁺ channel is one of the physiological targets and inhibition, which plays a role in the pathophysiology of depression revealed that all these compounds show consensus score in the range 2.71-3.68 indicating the summary of all forces of interaction. Further, compounds 4d, 4g and 4i exhibited potent antibacterial activity.

6 illus, 4 tables, 37 ref

003159   EZHILARASI M R, KHUMAR A B S, ELAVARASAN P (Chemistry Dep, Karpagam Academy of Higher Education, Coimbatore - 641 021, Email: mrezhilarasi@gmail.com) : Synthesis, in vitro antimicrobial evaluation, molecular docking studies and ADME prediction of furan-2-yl-morpholinophenylpyrimidine derivatives. Asian J Chem 2021, 33 (5), 1090 - 8.

A new series of novel 4-(furan-2-yl)-6-(4-morpholinophenyl)pyrimidine-amines (4a-c) were synthesized and characterized by elemental analysis and spectral analysis like IR, 1D ¹ H & ¹³C NMR. The synthesized compounds 4a-c were evaluated for their biological studies. The zone of inhibitions were examined for synthesized compounds 4a-c besides the identical set of microbial strains, especially that compound 4a against S. aureus, S. pyogenes, E. coli, compound 4b against P. aeruginosa has excellent antibacterial activity. Compound 4c shows good inhibition against C. albicans. Also in silico molecular docking and ADME predictions were carried for all the compounds. The docking studies were examined by two different proteins like 1UAG protein and 1OQA protein. in silico docking provides of the compounds have good docking score compared with the standard. In the ADME predictions all the compounds were met criteria. The synthesized compounds all of them obeyed the drug-likeness properties.

1 illus, 7 tables, 41 ref

003157   ACHARJEE B, DHINESHKUMAR E, BANDYOPADHYAY D, SRINIVASAN S (Chemistry Dep, Annamalai Univ, Annamalainagar - 608 002, Email: drssrinichem@gmail.com) : Synthesis, characterization and in vitro evaluation of 3-(4-(Methylthio)phenyl)-1-(thiophene-3-yl)prop-2-en-1-one. Asian J Chem 2021, 33 (5), 1077 - 84.

In present study, a novel 3-(4-(methylthio)phenyl)-1-(thiophene-3-yl)prop-2-en-1-one (1) was synthesized through the chalcone reaction. The FT-IR, ¹ H & ¹³C NMR and mass analysis, UV-visible and fluorescent spectroscopic system were utilized to characterize the synthesized compound. The charge density data was used to explain the characteristics of molecular systems. In addition, in the form of the complete and partial density of states, the HOMO-LUMO energy gap and electrostatic potential map, etc. and some quantum chemical insights have been obtained. Furthermore, to demonstrate the possible applications of thiophene-chalcone derivative (1) in nonlinear optics, the polarizability and first hyperpolarizability were measured. Molecular docking studies were also conducted in order to illustrate the over expression of estrogen receptor in 75% of 5J6A protein. The novel compound was tested for its anticancer and antioxidant activities of in vitro analyses. The substantial antioxidant activity was demonstrated by the newly synthesized compound 1.

8 illus, 11 tables, 33 ref

003156   KANTH K N R, KUMAR C J, TONY D E, MUNWAR S, NADENDLA R R, SAI C S (Chalapathi Institute of Pharmaceutical Sciences, Guntur - 522 034, Email: knrkanth2009@gmail.com) : Molecular docking studies, analgesic and anti-inflammatory screening of some novel quinazolin-4-one derivatives. Asian J Chem 2021, 33 (5), 1058 - 62.

Molecular docking studies was performed on 20 analogous novel quinazolin-4-one derivatives as cox-2 inhibitors using glide tool of maestro 11.4 application of Schrodinger software. Anti-inflammatory and analgesic activities were further evaluated for the compounds. Based on docking studies, the binding affinity of QZN-16 was found to be -10.32 kcal/mol. In order to understand the significance of R-substituents on the quinazoline-4-one nucleus, the findings of hydrogen bonding interactions between designated ligands with binding site region of 4cox were studied. The ligands which are having high docking score were subjected to pharmacological screening. The compound QZN-16 has shown analgesic and anti-inflammatory activity at a dose level of 50 and 100 mg/kg body weight, respectively when compared with standard drug indomethacin. The newly designed quinazoline-4-one derivatives may serve as lead molecules for further development.

2 illus, 3 tables, 26 ref

003155   REDDY A R, MUDDAM B, RAO A S, RAJANNA K C, REDDY A P, CHARY M T (Chemistry Dep, Osmania Univ, Hyderabad - 500 007, Email: kcrajannaou@yahoo.com) : Brønsted acid catalysis in the oxidation of purine based alkaloids by Mn(VII) in aqueous acetonitrile and sodium fluoride medium: A kinetic approach. Asian J Chem 2021, 33 (5), 1051 - 7.

Brønsted acid (HClO₄, H₂SO₄) catalyzed Mn(VII) oxidation of purine alkaloids such as caffeine, theophylline and theobromine in aqueous acetonitrile and sodium fluoride medium revealed first order kinetics in both [(Mn(VII)] and [Alkaloid] at constant acidity and temperature. Sodium fluoride was added to the reaction mixture in order to avoid/suppress auto catalytic reaction due to the generation of Mn(III) and Mn(IV) species during the course of Mn(VII) oxidations in acidic solutions. An increase in the Brønsted acids (HClO₄, H₂SO₄) concentration accelerated the rate of oxidation. Rate enhancements observed here in are analyzed by Zucker-Hammett, Bunnett and Bunnett-Olsen criteria of acidity functions. On the basis of observed Bunnett-Olsen criteria of acidity functions, the most plausible mechanism has been proposed with the involvement of water molecule in the slow step (as proton transferring agent).

6 illus, 5 tables, 40 ref

003154   ARATHI K N, KHAYUM K A, ALNASSER S M, MEROKA O J (Pharmaceutical Chemistry Dep, Sanjo Coll of Pharmaceutical Studies, Palakkad - 678 702, Email: kn.arathi@gmail.com) : COVID-19 Protease Inhibitor using Azole N-Mannich Bases: A molecular docking approach. Asian J Chem 2021, 33 (5), 1031 - 8.

Coronaviruses are the largest group of viruses belonging to the Nidovirales order, which includes Coronaviridae, Arteriviridae and Roniviridae families. In this work, a molecular modeling technique is adopted to find out the excellent moiety to inhibit the protease enzyme which is present in the coronavirus. Autodock 4.2 tool was used to find out the docking score of 32 ligands. The molinspiration server helps to find out the drug-likeness property and whether these ligands having a binding towards the protease enzyme. The synthetic N-Mannich bases of azole were docked with COVID-19 main protease in complex with an inhibitor N3 (PDB id: 6lu7). Among 32 ligand molecules, around 25 ligands showed an excellent binding score when compared to the standard drug favipiravir. The presence of dimethyl group in the pyrazole nucleus helps good interaction with protease enzyme. Among the Mannich bases, the secondary amine mannich base of piperazine considered as the best derivative to inhibit the protease enzyme.

5 illus, 4 tables, 23 ref

003152   THIPPESWAMY M, PUTTAGIDDAPPA M G, THIPPAIAH D, SATYANARAYAN N D (Chemistry Dep, Davangere Univ, Davangere - 577 002, Email: mamatha_gp2005@rediffmail.com, vmskt5@gmail.com) : Synthesis and characterization of poly(acrylamide) hydrogels as ph and salt sensitive material. Asian J Chem 2021, 33 (5), 1019 - 24.

This work reports the synthesis of poly(acrylamide) hydrogel and its characterization. Hydrogel will be synthesized by a chemical crosslinking method using sodium metabisulfite and potassium persulphate as initiators with crosslinker methylenebisacrylamide. The synthesized hydrogels were examined by FT-IR, SEM and TGA to determine chemical interactions in the polymer network. Moreover, the swelling study explains that hydrogels swelling capacity and it depends on the concentration of the crosslinking agent. The pH, temperature and salt solutions will impact on swelling properties. In acid and base solutions, the swelling ratio order is as follows HCl < CH₃COOH < HClO₄ < NaOH and the swelling ratio order in salt solutions is as follows: NaCl > CaCl₂ > AlCl₃.

11 illus, 1 table, 47 ref

003150   HARSHA K B, KAVITHA C V, SWAROOP T R, RANGAPPA S, RANGAPPA K (Studies in Organic Chemistry Dep, Mysore Univ, Mysuru - 570 006, Email: swarooptr@gmail.com, rangappaks@gmail.com) : A green synthesis of 1,5-benzodiazepines using reusable-heterogeneous silica sulfuric acid catalyst under solvent-free conditions and their antileukemic activity. Asian J Chem 2021, 33 (5), 1006 - 12.

1,5-Benzodiazepine derivatives are readily assembled from o-phenylene diamine and ketones containg α-hydrogen atoms by means of simple cyclocondensation via sp³ C-H activation promoted by an efficient heterogeneous silica sulfuric acid catalyst. Eco-friendliness, good yields, easy workup, reusable catalyst, short reaction times, high atom economy and solvent-free conditions are the noteworthy features of this protocol. These benzodiazepines are chosen for the evaluation of antiproliferative activity against different leukemia cell lines. Among the investigated compounds, 3g is the best antiproliferative agent against all the cell lines tested. Also, current preliminary analysis showed that compound 3g phosphorylates ERK1/2 and induces G1 arrest in K562 cells.

5 illus, 3 tables, 53 ref