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21.
A series of donor–acceptor compounds 2–6 have been synthesized, via Knoevenagel condensation reaction (using conventional method, as well as microwave method). The ferrocene unit acts as a donor, conjugated phenyl–acetylene linker act as a π-electron relay unit, and malononitrile, cyanoacetic acid, and indanone groups act as acceptor. The electronic absorption spectra displayed a broad intramolecular charge transfer (CT) band in the visible region (450–650 nm). The electrochemical studies suggest considerable donor–acceptor interaction. The single crystal X-ray structure of 2, and 3 are reported, the structure reveals that 2 is nearly planar compared to 3. The supramolecular structure of 2 exhibits intramolecular C–H–π, and C–H–N interaction, which leads to formation of 2D network, whereas compound 3 shows head to tail dimer formation through C–H–π, and π–π interaction. 相似文献
22.
M. B. Deshmukh S. D. Jadhav A. R. Mali A. W. Suryawanshi P. V. Anbhule S. S. Jagtap 《合成通讯》2013,43(23):2967-2971
The conjugate addition of organomanganese reagents to α,β‐unsaturated aldehydes and allylic bisacetate in presence of Me3Si‐Cl and tetrakis acetonitrile copper(I) tetrafluroborate is described. 相似文献
23.
Sunil U. Tekale Suresh S. Shisodia Sushma S. Kauthale Vivekanand B. Jadhav Nilesh S. Kanhe Sudha V. Bhoraskar 《合成通讯》2013,43(13):1849-1858
The present work introduces for the first time the catalytic utility of micron particulate aluminium nitride (AlN/Al) as a novel and reusable heterogeneous catalyst for the synthesis of bis(indolyl)methanes involving the electrophilic substitution of indoles on aldehydes. The catalyst is recyclable and works without any significant change in its catalytic activity. 相似文献
24.
Jagannath Jadhav Sharanabasappa KhanapaureRajanikant Kurane Rajashri SalunkheGajanan Rashinkar 《Tetrahedron letters》2013
An unprecedented methodology for the facile synthesis of 2-substituted 3-cyano-4-azaindoles using modified Madelung synthesis is described. The methodology relies on acid and amine coupling under very mild conditions. 相似文献
25.
Saikat Haldar Balaji S. Kale Dipesh D. Jadhav Hirekodathakallu V. Thulasiram 《Tetrahedron letters》2014
Pentacyclic triterpenoids α- and β-amyrin possess a wide range of biological and pharmacological activities. High structural similarity between these two structural isomers makes their chromatographic separation an ineffective and tedious choice. In this study, Candida rugosa lipase catalyzed separation protocol for the isolation of individual isomers has been developed. In the presence of vinyl acetate as the acyl donor, Candida rugosa lipase carried out acetylation of β-amyrin more efficiently as compared to α-amyrin leading to a kinetic separation. The conditions of transesterification reaction were optimized systematically, which was utilized to separate α- and β-amyrin from a mixture obtained from the latex of Plumeria obtusa. 相似文献
26.
Efficient metal-free oxidative aromatization of 2-aryloxycyclohex-2-en-1-ones was achieved by a combination of 2,3-dichloro-5,6-dicyano-p-benzoquinone (DDQ) and Amberlyst-15. The conditions for oxidative aromatization are mild and applicable for a variety of substrates, and Amberlyst-15 can be successfully recovered and recycled. 相似文献
27.
This study proposes an environment-friendly bioleaching process for recovery of metals from solders. Tin-copper (Sn-Cu), tin-copper-silver (Sn-Cu-Ag), and tin-lead (Sn-Pb) solders were used in the current study. The culture supernatant of Aspergillus niger removed metals faster than the culture supernatant of Acidithiobacillus ferrooxidans. Also, the metal removal by A. niger culture supernatant is faster for Sn-Cu-Ag solder as compared to other solder types. The effect of various process parameters such as shaking speed, temperature, volume of culture supernatant, and increased solder weight on bioleaching of metals was studied. About 99 (±1.75)?% metal dissolution was achieved in 60 h, at 200-rpm shaking speed, 30 °C temperature, and by using 100-ml A. niger culture supernatant. An optimum solder weight for bioleaching was found to be 5 g/l. Addition of sodium hydroxide (NaOH) and sodium chloride (NaCl) in the bioleached solution from Sn-Cu-Ag precipitated tin (85?±?0.35 %) and silver (80?±?0.08 %), respectively. Passing of hydrogen sulfide (H2S) gas at pH 8.1 selectively precipitated lead (57.18?±?0.13 %) from the Sn-Pb bioleached solution. The proposed innovative bioleaching process provides an alternative technology for recycling waste solders to conserve resources and protect environment. 相似文献
28.
Xin Hu Patricia M. Legler Noel Southall David J. Maloney Anton Simeonov Ajit Jadhav 《Journal of computer-aided molecular design》2014,28(7):765-778
Botulinum neurotoxin serotype A (BoNT/A) is the most lethal toxin among the Tier 1 Select Agents. Development of potent and selective small molecule inhibitors against BoNT/A zinc metalloprotease remains a challenging problem due to its exceptionally large substrate binding surface and conformational plasticity. The exosites of the catalytic domain of BoNT/A are intriguing alternative sites for small molecule intervention, but their suitability for inhibitor design remains largely unexplored. In this study, we employed two recently identified exosite inhibitors, D-chicoric acid and lomofungin, to probe the structural features of the exosites and molecular mechanisms of synergistic inhibition. The results showed that D-chicoric acid favors binding at the α-exosite, whereas lomofungin preferentially binds at the β-exosite by mimicking the substrate β-sheet binding interaction. Molecular dynamics simulations and binding interaction analysis of the exosite inhibitors with BoNT/A revealed key elements and hotspots that likely contribute to the inhibitor binding and synergistic inhibition. Finally, we performed database virtual screening for novel inhibitors of BoNT/A targeting the exosites. Hits C1 and C2 showed non-competitive inhibition and likely target the α- and β-exosites, respectively. The identified exosite inhibitors may provide novel candidates for structure-based development of therapeutics against BoNT/A intoxication. 相似文献
29.
Patil Seema P. Jadhav Sanjay N. Rode Chandrashekhar V. Shejwal Rajendra V. Kumbhar Arjun S. 《Transition Metal Chemistry》2020,45(6):403-411
Transition Metal Chemistry - A simple and efficient protocol for the ligand-free Mizoroki–Heck coupling reaction of various aryl bromides with different olefins has been reported by using in... 相似文献
30.
Ashwini Jadhav Kriti Gupta Pranay Ninawe Nirmalya Ballav 《Angewandte Chemie (International ed. in English)》2020,59(6):2215-2219
In this work, we have synthesized nanocomposites made up of a metal–organic framework (MOF) and conducting polymers by polymerization of specialty monomers such as pyrrole (Py) and 3,4‐ethylenedioxythiophene (EDOT) in the voids of a stable and biporous Zr‐based MOF ( UiO‐66 ). FTIR and Raman data confirmed the presence of polypyrrole ( PPy ) and poly3,4‐ethylenedioxythiophene ( PEDOT ) in UiO‐66‐PPy and UiO‐66‐PEDOT nanocomposites, respectively, and PXRD data revealed successful retention of the structure of the MOF. HRTEM images showed successful incorporation of polymer fibers inside the voids of the framework. Owing to the intrinsic biporosity of UiO‐66 , polymer chains were observed to selectively occupy only one of the voids. This resulted in a remarkable enhancement (million‐fold) of the electrical conductivity while the nanocomposites retain 60–70 % of the porosity of the original MOF. These semiconducting yet significantly porous MOF nanocomposite systems exhibited ultralow thermal conductivity. Enhanced electrical conductivity with lowered thermal conductivity could qualify such MOF nanocomposites for thermoelectric applications. 相似文献