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排序方式: 共有179条查询结果,搜索用时 15 毫秒
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Dr. Bugga Balakrishna Arjun Menon Dr. Kecheng Cao Sebastian Gsänger Dr. Sebastian B. Beil Julia Villalva Oleksandr Shyshov Oliver Martin Prof. Dr. Andreas Hirsch Prof. Dr. Bernd Meyer Prof. Dr. Ute Kaiser Prof. Dr. Dirk M. Guldi Prof. Dr. Max von Delius 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(42):18933-18945
3.
Anish Kumar Kadambar Balakrishna Kalluraya S. Madan Kumar 《Journal of heterocyclic chemistry》2020,57(11):3845-3855
One-pot three-component 1,3-dipolar cycloaddition reaction of azomethineylides generated from various combinations of isatin and ninhydrin with α-aminoacids to 5-nitrofurancontaining acetylenic ketones was carried out under thermal and microwave methods. The study of the regiochemical trend during the cycloaddition suggested that the nitrofuran ring exert no effect on the regiochemistry of the reaction as observed in the case of nitrofuran containing chalcones. The reason for the nil influence of the nitrofuran group is attributed to the increased electron density due to the triple bond. The newly synthesized compounds were docked to the active site of human anaplastic lymphoma kinase (ALK) to know the cancer cell toxicity in silico. The compounds 4b and 5a showed good binding interactions with the target in the active site. 相似文献
4.
Comparison of Templating Abilities of Urea and Thioruea During Photodimerization of Bipyridylethyelene and Stilbazole Crystals 下载免费PDF全文
Balakrishna R. Bhogala Burjor Captain Vaidhyanathan Ramamurthy 《Photochemistry and photobiology》2015,91(3):696-704
Photodimerization of cocrystals of four bispyridylethylenes and two stilbazoles with urea as a template in the solid state has been investigated following our success with thiourea. Four investigated olefins photodimerized quantitatively to a single dimer in the crystalline state only. The reactivity of urea–olefin crystals is understood on the basis of their packing arrangements in the crystalline state. In reactive crystals the adjacent reactive molecules are within 4.2 Å and parallel, whereas the unreactive ones have their adjacent molecules are farther than 4.6Å and nonparallel. Thus, with the knowledge of crystal packing the reactivity of urea–olefin crystals is predictable on the basis of Schmidt's topochemical postulates. The templating property of urea, similar to thiourea, derives from its ability to form hydrogen bonds with itself and the guest olefins. Despite the similarities in molecular structures of urea and thiourea their subtle electronic properties, yet to be fully understood, affect the crystal packing and consequently their reactivity in the crystalline state. Further work is needed to fully exploit the templating properties of urea. 相似文献
5.
Vignesh Nayak Mannekote Shivanna Jyothi Prof. R Geetha Balakrishna Dr. Mahesh Padaki Prof. Ahmad Fauzi Ismail 《ChemistryOpen》2015,4(3):278-287
Herein we present a new approach for the complete removal of CrVI species, through reduction of CrVI to CrIII, followed by adsorption of CrIII. Reduction of chromium from water is an important challenge, as CrIV is one of the most toxic substances emitted from industrial processes. Chitosan (CS) thin films were developed on plain polysulfone (PSf) and PSf/TiO2 membrane substrates by a temperature-induced technique using polyvinyl alcohol as a binder. Structure property elucidation was carried out by X-ray diffraction, microscopy, spectroscopy, contact angle measurement, and water uptake studies. The increase in hydrophilicity followed the order: PSf < PSf/TiO2 < PSf/TiO2/CS membranes. Use of this thin-film composite membrane for chromium removal was investigated with regards to the effects of light and pH. The observations reveal 100 % reduction of CrVI to CrIII through electrons and protons donated from OH and NH2 groups of the CS layer; the reduced CrIII species are adsorbed onto the CS layer via complexation to give chromium-free water. 相似文献
6.
Anish Kumar Kadambar Balakrishna Kalluraya Shalini Singh Vijaykumar Agarwal Bistuvalli Chandrashekarappa Revanasiddappa 《Journal of heterocyclic chemistry》2021,58(2):654-664
A simple and efficient one-pot three-component azide-alkyne cycloaddition of 5-chloro-1-phenyl-pyrazole-4-carbaldehyde with 2-(prop-2-yn-1-ylthio)-5-(substituted phenoxy)methyl-1,3,4-oxadiazole and sodium azide is reported. The newly synthesized compounds were characterized by spectral and analytical data. They were screened for in vitro anti-inflammatory activity by bovine serum albumin denaturation assay. All the tested compounds showed moderate anti-inflammatory activity, whereas three compounds ( 4d , 4i , and 4k ) showed excellent activity comparable with that of the standard drug diclofenac sodium. The quantitative structure-activity relationship (QSAR) study was carried out for anti-inflammatory activities of the synthesized compounds and developed a QSAR model. Inspired by their in vitro anti-inflammatory activities, they were docked to the active site of COX-2 to know the anti-inflammatory potency in silico. 相似文献
7.
Bakthavatchala Reddy Nemallapudi Grigory V. Zyryanov Balakrishna Avula Mallikarjuna Reddy Guda Sravya Gundala 《Journal of heterocyclic chemistry》2019,56(12):3324-3332
An effective and suitable meglumine‐catalyzed high‐yielding process was considered and engaged for the synthesis of new bis(indolyl)methanes at ambient temperature under aqueous conditions. The catalytic reaction proceeds very smoothly. Clean reaction, ease of product isolation/purification, easily available reactant and ecofriendly reaction conditions are the notable advantages of the present methodology. All the title compounds were characterized by IR, 1H, 13C NMR, and mass spectra. All the synthesized compounds were tested for antimicrobial activity, and the results indicated that most of the synthesized compounds exhibited excellent activity against the tested microorganisms. In this new series, compound 3l , having nitro substituent on the aromatic ring, showed exceptional potent inhibitory activity against Pseudomonas aeruginosa and Penicillium chrysogenum. 相似文献
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9.
Magnetic nanoparticle‐tethered Schiff base–palladium(II): Highly active and reusable heterogeneous catalyst for Suzuki–Miyaura cross‐coupling and reduction of nitroarenes in aqueous medium at room temperature 下载免费PDF全文
K. Manjunatha Tuhin S. Koley Vishal Kandathil Ramesh B. Dateer Geetha Balakrishna B. S. Sasidhar Shivaputra A. Patil Siddappa A. Patil 《应用有机金属化学》2018,32(4)
As a continuation of our efforts to develop new heterogeneous nanomagnetic catalysts for greener reactions, we identified a Schiff base–palladium(II) complex anchored on magnetic nanoparticles (SB‐Pd@MNPs) as a highly active nanomagnetic catalyst for Suzuki–Miyaura cross‐coupling reactions between phenylboronic acid and aryl halides and for the reduction of nitroarenes using sodium borohydride in an aqueous medium at room temperature. The SB‐Pd@MNPs nanomagnetic catalyst shows notable advantages such as simplicity of operation, excellent yields, short reaction times, heterogeneous nature, easy magnetic work up and recyclability. Characterization of the synthesized SB‐Pd@MNPs nanomagnetic catalyst was performed with various physicochemical methods such as attenuated total reflectance infrared spectroscopy, UV–visible spectroscopy, inductively coupled plasma atomic emission spectroscopy, energy‐dispersive X‐ray spectroscopy, field‐emission scanning electron microscopy, transmission electron microscopy, powder X‐ray powder diffraction, thermogravimetric analysis and Brunauer–Emmett–Teller surface area analysis. 相似文献
10.
Someshwarnath Pandey Balakrishna Kolli Sarada P. Mishra Asit B. Samui 《Journal of polymer science. Part A, Polymer chemistry》2012,50(6):1205-1215
Three new types of siloxane‐based photoactive liquid crystalline polymers containing azo side groups were synthesized through the click chemistry route. The polymers having molecular weight range of 14,000–34,000 g mol?1 were soluble in most of the polar solvents like chloroform, tetrahydrofuran, dimethylformamide, dimethyl sulfoxide, and dichloromethane. The photoresponsive trans–cis photoisomerization under UV radiation and cis–trans relaxation process in dark for the polymers were studied. The isomerization rate constants were found to be 0.01–0.04 sec?1 and 1.16*10?4–4.67*10?4 sec?1, respectively. It has been noted that the polymers showed high intensity absorption for n‐π* in chloroform. Both trans and cis forms of azide monomers having azo moiety exhibited molar extinction coefficient ( ? max) in the range of 22,000–33,000 L mol?1 cm?1. The thermotropic behavior of the polymers was studied by polarizing optical microscope (POM) and differential scanning calorimetry (DSC) experiments. Polymer P1 showed liquid crystalline textures of nematic droplets, whereas P2 showed smectic focal conic texture and nematic droplets. Polymer P1 was also studied for photomechanical bending on exposure to UV radiation. The polymers showed initial degradation temperature in the range of 210–275°C. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012 相似文献