Research related articles
Synthesis and characterization of alumina supported molybdosilicic acid (SiMo12/Al2O4) efficient solid acid catalyst for the synthesis of pyranopyrazole derivatives.
Shital B. Sukale, Dipak S. Aher, Kiran R. Khillare, Laxmikant D. Chavan and Sunil G. Shankarwar, Synthetic Communications, 2024, 54(10), 826-842.
Abstract: A series of highly reusable heterogeneous catalysts (10-40 wt.% SiMo12/Al2O3), consisting of molybdosilicic acid (SiMo12) impregnated on alumina (Al2O3) support was synthesized by the wetness impregnation method. The physicochemical properties of synthesized catalyst were studied using FT-IR, XRD, SEM, EDX, TEM, BET and TG-DTA analysis techniques. The study proves that the synthesized SiMo12 catalyst efficiently incorporated on the surface of Al2O3. The catalytic activity of prepared catalyst was investigated for the synthesis of pyranopyrazole(6-amino-4-phenyl-3-methyl-2,4-dihydropyrano[2,3-c]pyrazole-5carbonitrile) via cyclocondensation reaction of aldehydes, malononitrile, hydrazine hydrate and ethyl-acetoacetate under solvent-free conditions. Among different catalysts, 30% SiMo12 supported on to Al2O3 showed the highest catalytic activity. High yield, shorter reaction time, operational simplicity, solvent-free conditions and reusability of the catalyst are the distinct features of this protocol.
A simple and efficient protocol for the synthesis of quinoxaline derivatives using recyclable H5PW6Mo4V2O40.14H2O catalyst
Dipak S. Aher, Kiran R. Khillare, Laxmikant D. Chavan,Vinod A Shelke and Sunil G. Shankarwar, Synthetic Communications, 2022, 52(11-12), 1379-1388.
Abstract: Vanadium substituted Molybdotungstophosphoric acid (H5PW6Mo4V2O40·14H2O) was observed to be an effective solid catalyst for one-pot synthesis of several quinoxaline derivatives from the condensation reaction between various substituted o-phenylenediamine and various aromatic benzil compounds in ethanol: water (1:1) solvent under the reflux condition. The catalytic activity was tested under different reaction conditions to know the performance of the synthesized catalysts. Excellent yield, short reaction time, simple workup procedure, and reusability of the catalyst are the prominent features of our synthetic route.
Cesium salt of 2-molybdo-10-tungstophosphoric acid as an efficient and reusable catalyst for the synthesis of uracilderivatives via a green route
Kiran R Khillare, Dipak S Aher, Laxmikant D Chavan, Sunil G Shankarwar, RSC Advances 11 (54), 33980-33989, 2021.
Abstract: A solid catalyst, cesium salt of 2-molybdo-10-tungstophosphoric acid (Cs2.3H0.7PW10Mo2O40) named as Cs-3, was synthesized by a simple, cheap, clean, and eco-friendly method. The physicochemical properties of the synthesized catalyst were studied via FTIR spectroscopy, XRD, EDX, ICP-AES, SEM-TEM, and BET techniques. The precursor 2-molybdo-10-tungstophosphoric acid (H3PW10Mo2O40) was easily soluble in water and other polar solvents. Moreover, their cesium salts CsxH3−xPW10Mo2 with Cs content in the range x = 2.0–2.5 were insoluble in water and other polar solvents. The surface area of the precursor (5.483 m2 g−1) increased after partial proton exchange by Cs+ ions (111.732 m2 g−1), and all samples with x > 1 were resistant to leaching of active components and can be recycled without obvious loss of activity. This catalyst used for the synthesis of uracil derivatives via a green route under solvent free conditions at 70 °C gives higher yield within a shorter reaction time. The catalyst was found to be more active and reusable over nine runs with a negligible loss of activity.
Novel Poly(pyrrole-co-3-acetyl pyrrole)-WO3 nanocomposites modified gold electrode as electrocatalytic oxidation and reduction of H2O2
Nitin Dighore, Priya Dahare, Suresh Gaikwad, Anjali Rajbhoj, Adv. Mater. Lett. 2021, 12(10), 2115703.
Abstract: The fabrication of an electrochemical sensor based on novel poly(pyrrole-co-3acetyl pyrrole)-WO3 nanocomposites modified gold electrode (PPAP-WO3-AuE) and its electrocatalytic oxidation and reduction of hydrogen peroxide is described here. The PPAP-WO3 nanocomposites were synthesized by chemical method and characterized by different techniques. The WO3 nanoparticles incorporated with PPAP were confirmed by x-ray diffraction pattern, scanning electron microscopy and transmission electron microscope micrograph. The electrochemical behaviour of PPAP-WO3-AuE towards the electro catalytic oxidation and reduction of hydrogen peroxide was investigated by cyclic voltammetry, differential pulse voltammetry and square wave voltammetry. The observed DPVs and SWVs response depend linearly on concentration of hydrogen peroxide in the range of 1-10 mM and with limit of detection (LOD) is 1×10-4 M. The correlation coefficients were found as 0.991, 0.930 and sensitivity observed was 47.64 mA/mM.cm2 and 8.31mA/mM.cm2. These results indicate the PPAP-WO3-AuE exhibited good platform and could be used for electrochemical determination of hydrogen peroxide.
Novel hemicyanine sensitizers based on benzothiazole-indole for dye-sensitized solar cells: Synthesis, optoelectrical characterization and efficiency of solar cell
Sultan A. Al-horaibi, Ali A. Alrabie, Mohammed T. Alghamdi, Fares H. Al-Ostoot, Eman M. Garoon, Anjali S. Rajbhoj, Journal of Molecular Structure, 2021, 1224, 128836.
Abstract: Synthesis, characterization, and photovoltaic properties of three new hemicyanine sensitizers based benzothiazole-indoline (HC-TH, HC-IND1 and HC-IND2) were tested in DSSC with TiO2 film. These sensitizers have a higher molar absorption coefficient, and thus have better light harvesting properties. Electrochemical, theoretical, and spectroscopic methods were used to calculate energy levels of the dye molecules both in the excited state and in the ground state. The results obtained from the spectroscopy and Tafel studies show a marked increase in overall photoelectro-chemical cell output with Br-substitute at p-position in the hemicyanine sensitizer. Interestingly, HC-IND2 showed absorption of UV–Vis at a longer wavelength than HC-IND1 and HC-TH. This structural feature, as well as optical properties, would result in an improved efficiency of DSSC with a better photovoltaic output (4.01%) solar to electricity conversion efficiency compared to HC-IND1 and HC-TH.
The effect of Bis-carboxylic group of sqarylium dyes on the efficiency of dye sensitized solar cells,
Al-horaibi SA, Eman M. Garoon, Narendra A. Bhise, Suresh Gaikwad, Anjali Rajbhoj, Journal of Chemical Papers, 2020, 74, 1769–1778,
Abstract: Symmetric squarylium dye (SQIND1) with bi-carboxylic groups has been synthesized and photoelectrochemical properties have been studied in comparison with its non-functionalized analog groups (SQIND2). The experimental results showed that the introduction of anchor carboxylic groups in SQIND1 sensitizer provides a more intimate contact with nanoparticles TiO2 which increases the number of charge carriers transferred from the SQIND1 to the semiconductor. The theoretical calculations and absorbance results show that the electron density of LUMO of SQIND1 is delocalized in the whole chromophore, leading to strong electronic coupling between SQIND1 sensitizer and conducting band of TiO2, resulting in improved dye-sensitized solar cell efficiency compared to SQIND2. Hence, the SQIND1 sensitized exhibit better photovoltaic performance. Although, the absence of any linker groups in the SQIND1, then SQIND1 was perfect efficiently sensitized on porous TiO2 with the long UV–Vis and NIR region up to 800 nm of the spectrum and showed higher remarkable performance of values, such as η of 3.3%, a Jsc of 7.6 mA/cm2, a Voc of 0.59, and FF of 0.73.
Neem gum (Azadirachta indicia) facilitated green synthesis of TiO2 and ZrO2 nanoparticles as antimicrobial agents
Sonali A. Korde, Premkumar B. Thombre, Sudarshan S. Dipake, Jaiprakash N. Sangshetti, Anjali S. Rajbhoj, Suresh T. Gaikwad, Inorganic Chemistry communications, 2023, 153, 110777
Abstract: A green approach is used for the synthesis of monometallic and bimetallic metal oxide nanoparticles of titanium and zirconium using neem gum extract from the Azadirachta Indicia. The Nanosized titanium oxide (TiO2), zirconium oxide (ZrO2), and mixed titanium zirconium oxide (TiO2-ZrO2) particles were fabricated by sol–gel method using neem gum. Here the Neem gum has been applied as a capping and stabilizing agent, which is free from hazardous chemicals therefore, the reported method is environmentally benign, eco-friendly and cost-effective. The synthesized nanoparticles are characterized using TG-DTA, XRD, FTIR, UV–Vis, fluorescence spectroscopy, FE-SEM-EDX, and HR-TEM analysis techniques. Further these nanoparticles of TiO2, ZrO2,and TiZrO2 were evaluated for their antimicrobial activity. These nanoparticles exhibited efficient antibacterial activity against four different human pathogenic bacterial strains such as gram-negative Escherichia coli, Pseudomonas aeruginosa, and gram-positive Staphylococcus aureus, Bacillus substilis whereas antifungal activity against Candida albicans and Aspergillus niger fungal strains. The nanoparticles of TiO2 act as the most active antibacterial agent and show better antibacterial activity with MIC 93 ± 0.24, 96 ± 0.39, 91 ± 0.35, and 103 ± 0.22, respectively against Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, and Bacillus subtilis.
Zeolite ZSM-11 as a reusable and efficient catalyst promoted improve protocol for synthesis of 2,4,5-triarylimidazole derivatives under solvent free condition
S. S. Dipake, M. K. Lande, Anjali S. Rajbhoj, Suresh T. Gaikawad, Research on chemical intermediates, 2021, 47:2245–2261.
Abstract: Zeolite ZSM-11 catalyst was prepared by hydrothermal method and characterized by FTIR, XRD, SEM, HRTEM, EDS, and BET analysis techniques. The catalyst shows good catalytic activity toward synthesis of 2,4,5-triarylimidazole derivatives which is prepared by using benzil, aldehyde and ammonium acetate in solvent-free condition. The reaction, one pot synthesis is highly adaptable and eco-friendly and has several merits such as short reaction time, mild reaction conditions, and high yield. The ease of reusability and recovery of catalyst for five consecutive reactions makes this protocol highly suitable
An efficient green protocol for the synthesis of 1,2,4,5-tetrasubstituted imidazoles in presence of ZSM-11 zeolite as a reusable catalyst
S. S. Dipake, V. D. Ingale, S. A. Korde, M. K. Lande, Anjali S. Rajbhoj, Suresh T. Gaikwad, RSC advances, 2022, 12, 4358-4369.
Abstract: In this study, we have synthesized a series of ZSM-11 zeolite catalysts using tetrapropyl ammonium hydroxide as a structure-directing agent through a highly efficient hydrothermal method. The series of catalysts were studied by different techniques such as FT-IR spectroscopy, XRD, FE-SEM, HR-TEM, EDS, pyridine-FT-IR spectroscopy, and BET analysis. We focused on varying reaction time intervals from 18 to 48 hours to investigate the effect on catalytic activities of the synthesized series of catalysts. The percentages of aluminum increased in the framework of zeolites with increasing crystallinity, surface area, external surface area, and acidity in the series of ZSM-11 zeolites by increasing the time from 18 to 48 h. Then, we studied the catalytic activity of a series of ZSM-11 zeolites and found that the ZSM-11 zeolite (48 h) possesses higher catalytic activity towards the synthesis of 1,2,4,5-tetrasubstituted imidazoles under solvent-free conditions. The present protocol scored well with excellent yield, short reaction time, clean reaction profiles, low catalyst loading, and no tedious workup. The catalyst (ZSM-11 zeolite 48 h) was recycled and reused in five runs without any considerable loss of activity and product yield.
Water compatible silica supported iron trifluoroacetate and trichloroacetate: as prominent and recyclable Lewis acid catalysts for solvent-free green synthesis of hexahydroquinoline-3-carboxamides
D. P. Gholap, R. Huse, S. Dipake and M. K. Lande, RSC Adv., 2023, 13, 23431-23448
Abstract: Silica supported iron trifluoroacetate and iron trichloroacetate green Lewis acid catalysts were developed by a novel, cheap, environment-friendly approach and utilized in the synthesis of hexahydroquinoline-3-carboxamide derivatives. The structure and morphology of the prepared Lewis acid catalysts were studied by FTIR, PXRD, FE-SEM, HR-TEM, EDX, BET, TGA and NH3-TPD techniques. The present catalysts shows maximum conversion efficiency in hexahydroquinoline-3-carboxamide derivatives synthesis at 70 °C in solvent free reaction condition with best product yield in a short reaction time. Both catalysts are reusable and simple to recover, and perform meritoriously in water as well as in a variety of organic solvents. The key advantages of the current synthetic route are permitting of a variety of functional groups, quick reaction time, high product yield, mild reaction condition, recyclability of catalyst and solvent-free green synthesis. This makes it more convenient, economic and environmentally beneficial.
Water compatible silica supported iron trifluoroacetate and trichloroacetate: as prominent and recyclable Lewis acid catalysts for solvent-free green synthesis of hexahydroquinoline-3-carboxamides
D. P. Gholap, R. Huse, S. Dipake and M. K. Lande, RSC Adv., 2023, 13, 23431-23448
Abstract: Silica supported iron trifluoroacetate and iron trichloroacetate green Lewis acid catalysts were developed by a novel, cheap, environment-friendly approach and utilized in the synthesis of hexahydroquinoline-3-carboxamide derivatives. The structure and morphology of the prepared Lewis acid catalysts were studied by FTIR, PXRD, FE-SEM, HR-TEM, EDX, BET, TGA and NH3-TPD techniques. The present catalysts shows maximum conversion efficiency in hexahydroquinoline-3-carboxamide derivatives synthesis at 70 °C in solvent free reaction condition with best product yield in a short reaction time. Both catalysts are reusable and simple to recover, and perform meritoriously in water as well as in a variety of organic solvents. The key advantages of the current synthetic route are permitting of a variety of functional groups, quick reaction time, high product yield, mild reaction condition, recyclability of catalyst and solvent-free green synthesis. This makes it more convenient, economic and environmentally beneficial.
Water compatible silica supported iron trifluoroacetate and trichloroacetate: as prominent and recyclable Lewis acid catalysts for solvent-free green synthesis of hexahydroquinoline-3-carboxamides
D. P. Gholap, R. Huse, S. Dipake and M. K. Lande, RSC Adv., 2023, 13, 23431-23448
Abstract: Silica supported iron trifluoroacetate and iron trichloroacetate green Lewis acid catalysts were developed by a novel, cheap, environment-friendly approach and utilized in the synthesis of hexahydroquinoline-3-carboxamide derivatives. The structure and morphology of the prepared Lewis acid catalysts were studied by FTIR, PXRD, FE-SEM, HR-TEM, EDX, BET, TGA and NH3-TPD techniques. The present catalysts shows maximum conversion efficiency in hexahydroquinoline-3-carboxamide derivatives synthesis at 70 °C in solvent free reaction condition with best product yield in a short reaction time. Both catalysts are reusable and simple to recover, and perform meritoriously in water as well as in a variety of organic solvents. The key advantages of the current synthetic route are permitting of a variety of functional groups, quick reaction time, high product yield, mild reaction condition, recyclability of catalyst and solvent-free green synthesis. This makes it more convenient, economic and environmentally beneficial.
Silica supported lanthanum trifluoroacetate and trichloroacetate as an efficient and reusable water compatible Lewis acid catalyst for synthesis of 2,4,5-triarylimidazoles via a solvent-free green approach
D. P. Gholap, R. Huse, S. Dipake and M. K. Lande, RSC Adv., 2023, 13, 2090-2103
Abstract: In the present research article, we have developed solid heterogenous silica supported lanthanum trifluoroacetate and trichloroacetate as green Lewis acid catalysts. These catalysts were synthesized by a novel, simple, cheap, clean, and environment friendly method. The physicochemical properties of the prepared catalysts were well studied and characterized by sophisticated spectroscopic techniques such as FTIR, TGA, XRD, EDX, SEM, TEM and BET analysis. The catalyst was utilized in the synthesis of arylimidazole derivatives via green protocols under solvent-free conditions at 70 °C with a higher yield, mild reaction conditions and a short reaction time. The catalyst works superiorly in water as well as in various organic solvents as a reusable and easily recoverable catalyst.
Preparation, characterization and catalytic application of Zn-based metal–organic framework catalyst for synthesis of 3,3-(arylmethylene)bis-1H-indole derivatives
Vaishali N Rathod, Ganesh T Pawar, Suresh T Gaikwad, Machhindra K Lande, Journal of Chemical Technology & Biotechnology; 2022, 97(8), 2005-2012
Abstract: A mesoporous zinc-based pyridine-2,5-dicarboxylate metal–organic framework (Zn-based MOF) catalyst was prepared by a solvothermal method. The catalytic potency of Zn-based MOF for the one-pot synthesis of 3,3-(arylmethylene)bis-1H-indole derivatives was investigated. Various analytical techniques were used to characterize the physicochemical structure of Zn-based MOF catalyst, including powder X-ray diffraction, thermogravimetric analysis, scanning electron microscopy–energy-dispersive X-ray analysis, Fourier transform infrared spectroscopy and Brunauer–Emmett–Teller surface area analysis. Zn-based MOF was then employed as a catalyst for the catalytic one-pot transfer synthesis of 3,3-(arylmethylene)bis-1H-indole derivatives. Optimizations of Zn-based MOF catalyst in terms of effect of solvent and reaction time were investigated. Zn-based MOF catalyst was synthesized by solvothermal treatment, characterized and used as a Lewis acid catalyst for the synthesis of biologically active 3,3′-(arymethylene)bis-1H-indole derivatives. The catalyst offers notable benefits such as reusability of catalytic character, easy separation, nontoxicity, large pore size and providing excellent yield of 3,3′-phenylmethylene-1H-indole derivatives. Zn-based MOF was confirmed as containing tetragonal phase with large pore diameter, morphology looking like a spherical core and exhibiting no significance loss of catalytic performance when used in organic synthesis for three to four reaction runs. Thereby Zn-based MOF was evidenced as showing excellent catalytic activity. © 2022 Society of Chemical Industry (SCI).
New 1,2,3-triazole tethered-1,4-dihydropyridines as potential antioxidant agents: Synthesis and molecular docking study
B. Danne, K. V. Lathi, J. N. Sangshetti, V. M. Khedkar, L. D. Khalse, B. B. Shingate Journal of Molecular Structure, 2024, 1299, 137129
We have designed the molecules containing 1,2,3-triazole and 1,4-dihydropyridine pharmacophoric scaffolds in a single molecular framework by using molecular hybridization approach. Accordingly, we have planned and executed for the synthesis of a library of aryl-1,2,3-triazole incorporated 1,4-dihydropyridines and evaluated for their antioxidant activity. The compounds 12o, 12s and 12t showed excellent antioxidant activity with an IC50 values of 08.34 ± 0.17, 08.04 ± 0.17 and 08.80 ± 0.15 µg/mL, respectively. The compound 12a and 12m exhibited excellent antioxidant activity with IC50 values of 09.11 ± 0.34 and 11.39 ± 0.94 µg/mL, respectively. Furthermore, the compound 12k and 12n showed very good antioxidant activity with IC50 values of 12.22 ± 0.43 and 16.05 ± 0.11 µg/mL, respectively. In silico molecular docking study was performed to examine their binding modes and interactions with myeloperoxidase (MPO) enzyme which exhibited excellent correlation with observed antioxidant activites. Finally, in silico ADMET properties of the synthesized compounds were also investigated. The obtained results showed that most of the synthesized compounds had a positive drug-likeness profile.
Curcumin‐based bioactive heterocycles derived via multicomponent reactions.
A. A. Nagargoje, M. H. Shaikh, B. B. Shingate, Archiv der Pharmazie, 2023, e2300171
Abstract: Curcumin is an important phytochemical, found in the Asian countries, especially in the Indian subcontinent. The use of this "privileged natural product" in the diversity-oriented synthesis of curcumin-based heterocycles via multicomponent reactions (MCRs) is the subject of interest for many medicinal chemists across the globe. This review particularly focuses on the reactions involving curcuminoids as one of the reactants in the MCRs of curcuminoid to synthesize curcumin-based heterocycles. Also, the various pharmacological activities of curcumin-based heterocycles generated via the MCR approach are discussed. The research work published in the last 10 years is in the focus of this review article.
New 1, 2, 3-Triazole-Appended Bis-pyrazoles: Synthesis, Bioevaluation, and Molecular Docking.
A. B Danne, M. V Deshpande, J. N Sangshetti, V. M. Khedkar, B. B. Shingate, ACS Omega, 2021, 6, 24879-24890.
Abstract: The present work describes design of a small library of new 1,2,3-triazole-appended bis-pyrazoles by using a molecular hybridization approach, and the synthesized hybrids were evaluated for their antifungal activity against different fungal strains, namely, Candida albicans, Cryptococcus neoformans, Candida glabrata, Candida tropicalis, Aspergillus niger, and Aspergillus fumigatus. All the compounds exhibited broad-spectrum activity against the tested fungal strains with excellent minimum inhibitory concentration values. The molecular docking study against sterol 14α-demethylase (CYP51) could provide valuable insights into the binding modes and affinity of these compounds. Furthermore, these compounds were also evaluated for their antioxidant activity, which also resulted in promising data.
Polyaniline based highly selective electrochemical sensor for ascorbic acid determination: Performance studies towards real sample analysis
R. A Kale, S. C. Dhawale, B. B. Mulik, A. Adhikari, B. R. Sathe, Journal of Industrial and Engineering Chemistry, 2024, 136, 167-176
Abstract: The electrocatalytic behavior of polyaniline (PAni) towards the electro-oxidation of L-ascorbic acid (L-AA) was studied by using cyclic voltammetry. PAni synthesized by oxidative polymerization method, and characterized by using high resolution-transmission electron microscopy (HR-TEM), scanning electron microscopy coupled with energy dispersive X-ray analysis (SEM-EDAX) confirms large globular structures, X-ray diffraction (XRD) analysis revealed that PAni with amorphous nature, whereas Fourier-transform infrared spectroscopy (FTIR) of PAni shows C-N stretching, X-ray photoelectron spectra (XPS) attributes the peaks C1s, N1s and O1s. UV–visible spectra revealed PAni is conducting and its Brunauer–Emmett–Teller (BET) surface area is 343.67 m2/g demonstrates it has high surface area and good adsorption ability. The PAni electrocatalyst showed an excellent selectivity towards L-AA in presence of different inorganic and biological expedients under similar conditions. A limit of detection (LOD) and limit of quantification (LOQ) were calculated found to be 5.1 µM and 17.2 µM respectively. Furthermore, the electrocatalyst activity towards L-AA were also validated for real sample analysis like lemon juice and vitamin-C tablet by quantifying the L-AA. The exceptionally higher conductivity and good electrocatalytic performance of PAni make it a promising material for sustainable energy generation and environmental protection without relying on metals or harmful chemicals.
Multiwalled carbon nanotubes decorated with molybdenum sulphide (MoS2@ MWCNTs) for highly selective electrochemical picric a cid (PA) determination
R. P. Dighole, A. V Munde, B. B. Mulik, S. C Dhawale, B. R. Sathe, Applied Surface Science, 2024, 659, 159856,
Abstract: Nitrophenols are industrially versatile yet environmentally detrimental compounds. Herein, we have synthesised molybdenum sulphide based dichalcogenide supported multiwalled carbon nanotubes i.e. MoS2@MWCNTs electrocatalyst by simple wet chemical method for PA determination. The successful decoration of MoS2 over MWCNTs were confirmed by various characterizations techniques including scanning electron microscopy (SEM) shows MoS2 layers grown on MWCNTs and having average size is -80 nm. Energy dispersive X-ray analysis (EDAX) reveals elements are homogenously distributed in nanocomposite. High resolution-transmission electron microscopy (HR-TEM) shows increase in average diameter after decoration of MoS2 over MWCNTs from 30 nm to 70 nm. The Fourier transform infrared (FT-IR) analysis suggests the presence of Mo-S stretching frequency at 605 cm-1 in addition to hydroxyl, carbonyl, C-C, C-O stretching frequencies are also observed. In Raman spectrum from apart D and G bands, the characteristic intense bands E2g1 and A1g of MoS2 were pointed towards presence of molybdenum and sulphur. The X-ray diffraction (XRD) confirms synthesised electrocatalyst is in hexagonal crystal structure with P63/mmc space group. The X-ray photoelectron spectroscopy (XPS) reveals that for Mo 3d is found to be two characteristics peaks at 231.2 eV and 233.2 eV corresponds to Mo4+ 3d3/2 and 3d5/2 respectively. The peak at 229 eV corresponds to S 2s. Whereas, the signal appears at 162.7 eV, 165 eV, 169 eV and 170 eV shows sulphur is in 2S3/2 and 2S5/2 states. Electrochemical performance was examined by cyclic voltammetry (CV) tests. The Electrocatalyst is highly selective, having appreciable anti-interference property, lower limit of detection (LoD), i.e., 0.5 μM with wide linear range. The low Rct and high k⁰ pointed that MoS2@MWCNTs performed better towards electrochemical detection of PA.
Highly efficient manganese oxide decorated graphitic carbon nitrite electrocatalyst for reduction of CO2 to formate
Balaj i B. Mulik, Ajay V. Munde, B. D. Bankar, A. V. Biradar, B. R. Sathe, Catalysis Today, 2021, 370, 104-113
Abstract: Herein, an effective electrocatalyst exploiting non-noble metal oxide-containing of manganese oxide (MnO2) supported on graphitic carbon nitride (g-C3N4) for reduction of CO2 over a wide range of potential. The MnO2 decorated g-C3N4 nanocomposite was synthesized by precipitation, followed by calcination to attain uniform distribution of the MnO2. The MnO2 was found α-MnO2 crystal structure with a size of ∼0.5–2 nm having interlinear lattice spacing of 0.243 nm seen on the layer of g-C3N4 (50−100 nm). The high defective sites observed on MnO2/g-C3N4 (ID/IG) is 1.91 than pristine g-C3N4 (ID/IG) is 0.054. The core spectrum analysis of XPS showed N, C, O and Mn atoms in the as-synthesized composite. The electrocatalysts were executed for electrocatalytic hydrogenation of CO2 at lower onset potential of −0.14 V vs. RHE into C1 products having Faradaic efficiencies (FE) of 8, 47.45 and 65.28% at an applied potential of −0.14, −0.34 and −0.54 V vs. RHE, respectively. The catalyst has further used for the chemical hydrogenation of CO2, and the good yield of formic acid was 9603.28 μmol obtained. The enrichment of the electrocatalytic activities was observed due to the synergetic effect of both MnO2 and g-C3N4. This methodology will be applicable for industrial applications and it will help control environmental issues.
Silica-supported Bi2O3[sbnd]Cr2O3 nanocomposite: Efficient catalyst for Pyrano[3,2-c]chromenes synthesis and DFT studies
Mueataz G. Thabet, Mohd. Aslam, Prashant Singh, Giribala M. Bondle, Journal of Molecular Structure, 2025, p. 139624
Abstract: Synthesis of a new nanocomposite catalyst, consisting of Bi and Cr loaded on silica is achieved using the incipient wetness impregnation approach. This catalyst is used to synthesize Dihydropyrano[3,2-c]chromene scaffold via one-pot reaction method involves the mixture of 4-Hydroxycoumarin, Malononitrile or Ethyl cyanoacetate and different aromatic aldehydes in methanol at room temperature. The catalyst was characterized using several methods such as XRD, FT-IR, FE-SEM, and EDS. The efficacy of this heterogeneous catalyst was evaluated by loading different wt% of bismuth and chromium on silica. The wt% of on SiO2 was proven to be extremely suitable catalytic activity to get high yield of products (up to 98 %) in short span of time (up to 15 min) with high selectivity as outlined in the proposed mechanism. Additionally, density functional theory (DFT) studies of the Dihydropyrano[3,2-c]chromenes were conducted to elucidate their electronic properties and reactivity. It provided insights into the frontier molecular orbitals, electrostatic potential maps of these synthesized compounds, offering valuable information for future rational design of related Chromene-based molecules. The catalyst was successfully recovered and reused for up to five reaction cycles without any significant decline in its catalytic efficiency. Future work will focus on expanding the use of this catalyst for synthesizing library of bioactive compounds.
Design, synthesis and molecular docking study of novel triazole–quinazolinone hybrids as antimalarial and antitubercular agents.
UV Mhetre, NB Haval, G. M. Bondle, SS Rathod, PB Choudhari, J Kumari, D Sriram, KP Haval, Bioorganic & Medicinal Chemistry Letters 108, 129800, 2024.
Abstract: In a quest to discover new antimalarial and antitubercular drugs, we have designed and synthesized a series of novel triazole–quinazolinone hybrids. The in vitro screening of the triazole–quinazolinone hybrid entities against the plasmodium species P. falciparum offered potent antimalarial molecules 6c, 6d, 6f, 6g, 6j & 6k owing comparable activity to the reference drugs. Furthermore, the target compounds were evaluated in vitro against Mycobacterium tuberculosis (MTB) H37Rv strain. Among the screened compounds, 6c, 6d and 6l were found to be the most active molecules with a MIC values of 19.57–40.68 μM. The cytotoxicity of the most active compounds was studied against RAW 264.7 cell line by MTT assay and no toxicity was observed. The computational study including drug likeness and ADMET profiling, DFT, and molecular docking study was done to explore the features of target molecules. The compounds 6a, 6g, and 6k exhibited highest binding affinity of −10.3 kcal/mol with docked molecular targets from M. tuberculosis. Molecular docking study indicates that all the molecules are binding to the falcipain 2 protease (PDB: 6SSZ) of the P. falciparum. Our findings indicated that these new triazole–quinazolinone hybrids may be considered hit molecules for further optimization studies.
Synthesis, characterization and catalytic evaluation of ZrCl4: Mg (ClO4)2 for the synthesis of 1, 3-diaryl- 3-(phenylthio) propan-1-one
ST Atkore, G. M. Bondle, VT Kamble, R Varala, SF Adil, MR Hatshan. Journal of Saudi Chemical Society, 25 (12), 101359, 2021.
Abstract: Herein we demonstrate a novel tandem aldol condensation-thia-Michael addition process using a bimetallic catalyst (ZrCl4:Mg(ClO4)2). The novel bimetallic catalyst performs under very mild conditions. The catalyst helps in the efficient synthesis of β-mercapto carbonyl derivatives from chalcones and thiols in one-pot method. We successfully used the zirconium tetrachloride in combination with magnesium perchlorate in a specific ratio which is considered as green catalyst and efficiently worked for the synthesis of β-mercapto carbonyl derivatives at room temperature. This is the first report which presents the use of ZrCl4:Mg(ClO4)2 without calcination. Significant advantages of this method are that the reaction is performed under mild conditions, shows good selectivity and high yield, within short reaction times and easy workup. This method minimizes waste disposal problems as well, which makes present method highly efficient and convenient. The synthesized bimetallic catalyst was characterized by different analytical techniques such as XRD and SEM. Subsequently, the synthesized β-mercapto carbonyl products were identified by using FTIR, NMR, GC–MS and CHN elemental analyzer.
Co-existence of Extended Spectrum β-Lactamase and carbapenemase-producing genes from Diarrheagenic Enteric pathogens isolated in a tertiary care hospital
Kharat, A.A., Makwana, N., Kadam, D.G., Chavan, A. S., Kulkarni, J.A.,Kharat, A.S., Acta Biochimica Polonica, 2023, 70 (1), 69-76.
Abstract: Multiple drug resistance (MDR) among bacterial pathogens is a growing concern that clinicians are facing worldwide. Diarrhea among infants is frequent and is caused by various bacterial and viral infectious agents. Two hundred and twelve stool specimens were collected from pediatric patients from a rural quaternary hospital in Barshi, Sholapur, India, between March and December 2017. Total 180 specimens were positive for various bacterial pathogens, while the remaining 32 diarrhea cases may have been caused by a viral or uncultured bacterial pathogen. Identification of the bacterium and its antibiotic susceptibility were primarily carried out with VITEK-2. Distribution of diarrhea-causing bacteria among the 180 samples was as follows: 61.11% (110) Escherichia coli, 30.55% (55) Klebsiella pneumoniae, 4.44% (8) Proteus mirabilis, 2.22% (4) Shigella spp. 1.11% (2) Morganella morganii and 0.55% (1) each for Enterobacter cloacae and Citrobacter koseri. There was a co-existence of multiple genetic traits conferring extreme drug resistance (XDR) status to 19 isolates, 17 of which were determined to be E. coli and one each of E. cloacae and C. koseri. Antibiotype determination using VITEK-2 and polymerase chain reaction (PCR) amplification of the genetic traits indicated the co-existence of blaTEM and blaCTX-M15 isolates in all 19 isolates, with the exception of E. cloacae. Results showed that 10 out of 19 strains expressed the AmpC cephalosporinase blaCMY-2 gene, whereas metallo-carbapenemase was expressed in four isolates. Distribution of blaNDM-11 and acquired penicillinase blaSHV-1 resistance among 180 clinical isolates is discussed in the light of ESBL traits. This is the first report from the rural part of Maharashtra India showing that as many as 10.55% of the pathogenic strains were XDR, a step ahead of MDR.
CAL-B accelerated novel synthetic protocols for 3, 3’-arylidenebis-4-hydroxycoumarins and dimethyl ((substituted phenyl)(phenylamino) methyl) phosphonates
Chavan, A. S., Kharat, A. S., Bhosle, M. R., Dhumal, S.T., Mane, R.A., Research on Chemical Intermediates.2021, 47, 4497-4512.
Abstract: Green protocols for the syntheses of 3,3′-arylidenebis-4-hydroxycoumarins and dimethyl ((substituted phenyl) (phenylamino)methyl) phosphonates have been first time developed using biocatalyst, CAL-B (lipase). These are carried at room temperature under stirring and are convenient and cost effective. The developed protocols are environmentally acceptable and are giving better to excellent yields of the titled products.
Water mediated and Baker’s yeast accelerated novel synthetic protocols for tetra hydrobenzo [a] xanthene-11-ones and pyrazolo[3, 4-b] quinolines
Chavan, A.S., Kharat, A.S., Bhosle, M.R., Mane, R.A., Heterocyclic Communications, 2021, 51(13), 103-101963-1973.
Water mediated and baker’s yeast catalyzed, efficient synthetic routes have been first time developed for multicomponent cyclocondensations leading to bioactive tetrahydro benzo[a]xanthene-11-ones (4a–h) and pyrazolo[3,4-b]quinolines (7a–i). The developed protocols are conducted at room temperature and gave better to excellent yields of the titled compounds. The biocatalytical resource, activated baker’s yeast is readily available, and biodegradable. These protocols are more convenient, scalable, and obey most of the green principles also. The developed protocols are cost effective and better in operation than existing ones.