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51.
One‐Pot Three‐Component Domino Reaction for the Synthesis of Novel Spiro Indolinyl Isoxazolo[2,3‐c][1,3,5]Thiadiazepinones Catalyzed by PTSA 下载免费PDF全文
Rajanarendar Eligeti Nagaraju Dharavath Ramakrishna Saini 《Journal of heterocyclic chemistry》2014,51(6):1814-1817
The synthesis of novel spiro indolinyl isoxazolo[2,3‐c] [1,3,5]thiadiazepinones has been achieved by using one‐pot three‐component domino reaction from 3‐amino‐5‐methylisoxazole, substituted isatins, and mercapto acetic acid by employing p‐toluene sulfonic acid as Lewis acid catalyst. The salient features of the present method are mild reaction conditions, cost effective, environmentally benign, high yields of products and operational simplicity. 相似文献
52.
Jeshma Kovvuri Burri Nagaraju C. Ganesh Kumar K. Sirisha Cheemalamarri Chandrasekhar Abdullah Alarifi Ahmed Kamal 《Journal of Saudi Chemical Society》2018,22(6):665-677
Catalyst-free one-pot CN and CC bond formation is described as a simple and ecofriendly method for the synthesis of pyrazole-aniline linked coumarin derivatives. Employing this protocol, a series of derivatives were synthesized in good to excellent yields and tested against different bacterial strains as well as fungal strains. Most of the compounds exhibited potential antimicrobial activity against both Gram-positive and Gram-negative bacterial strains. Among them, the compounds 4b, 4e, 4?h, 4i and 4?k exhibited promising activity on all the tested bacterial strains with values ranging between 1.9 and 7.8?µg/mL. In addition, these compounds were tested against various fungal strains and were found to exhibit potential antifungal activity. Fascinatingly, among the tested derivatives, the compounds 4e, 4?h and 4i were found to be equipotent to miconazole (positive control) against some of the tested fungal strains. Moreover, these compounds showed promising bactericidal, Candida-cidal and biofilm inhibition activities. Further, mechanistic study was carried out with the most active derivative 4i indicated that these compounds inhibit the ergosterol biosynthesis pathway. 相似文献
53.
Nagaraju Barsu Md. Atiur Rahman Malay Sen Prof. Basker Sundararaju 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(27):9135-9138
An efficient and external oxidant‐free, Cp*CoIII‐catalyzed C(sp3)?H bond amidation of 8‐methylquinoline, using oxazolone as an efficient amidating agent, is reported for the first time under mild conditions. The reaction is selective and tolerates a variety of functional groups. Based on previous reports and experimental results, the deprotonation pathway proceeds through an external base‐assisted concerted metalation and deprotonation process. 相似文献
54.
Hanumanthrayappa Manjunatha Doddahalli Hanumantharayudu Nagaraju Gurukar Shivappa Suresh Thimmappa Venkatarangaiah Venkatesha 《Electroanalysis》2009,21(20):2198-2206
The properties of graphite electrode (Gr) modified with poly(diallyl dimethyl ammonium chloride) (PDDA) for the detection of uric acid (UA) in the presence of dopamine (DA) and high concentration of ascorbic acid (AA) have been investigated by cyclic voltammetry, differential pulse voltammetry and chronoamperometry. The polymer modified graphite electrode was prepared by a very simple method just by immersing the graphite electrode in PDDA solution for 20 minutes. The PDDA/Gr modified electrode displayed excellent electrocatalytic activity towards the oxidation of UA, DA and AA compared to that at the bare graphite electrode. The electrochemical oxidation signals of UA, DA and AA are well resolved into three distinct peaks with peak potential separations of 220 mV, 168 mV and 387 mV between AA‐DA, DA‐UA and AA‐UA respectively in cyclic voltammetry studies and the corresponding peak potential separations are 230 mV, 130 mV and 354 mV respectively in differential pulse voltammetry. The lowest detection limits obtained for UA, DA and AA were 1×10?7 M, 2×10?7 M and 800×10?9 M respectively. The PDDA/Gr electrode efficiently eliminated the interference of DA and a high concentration of AA in the determination of UA with good selectivity, sensitivity and reproducibility. The modified electrode was also successfully applied for simultaneous determination of UA, DA and AA in their ternary mixture. 相似文献
55.
Ganganagappa Nagaraju Pallellappa Chithaiahb Siddaramanna Ashokac Narayanappa Mahadevaiah 《Crystal Research and Technology》2012,47(8):868-875
In this paper, we report a synthesis, characterization and electrochemical properties of V2O5 nanobelts. V2O5 nanobelts have been prepared via hydrothermal treatment of commercial V2O5 in acidic (HCl/H2SO4) medium at relatively low temperature (160 °C). The hydrothermally derived products have been characterized by powder X‐ray diffraction (XRD), Fourier transform infrared spectroscopy (FT‐IR), Raman spectroscopy, X‐ray photo electron spectroscopy (XPS), UV‐Vis spectroscopy, Scanning/Transmission electron microscopy (SEM/TEM). XRD pattern of V2O5 nanobelts show an orthorhombic phase. From the FTIR spectrum, the peak observed at 1018 cm−1 is characteristic of the stretching vibration mode of the terminal vanadyl, V = O. The UV‐Vis absorption spectrum of V2O5 nanobelts show maximum absorbance at 430 nm, which was blue‐shifted compared to that of bulk V2O5. TEM micrographs reveal that the products consist of nanobelts of 40‐200 nm in thickness and several tens of micrometers in length. The electrochemical analysis shows an initial discharge capacity of 360 mAh g−1 and its almost stabilized capacity is reached to 250 mAh g−1 after 55 cycles. A probable reaction mechanism for the formation of orthorhombic V2O5 nanobelts is proposed. 相似文献
56.
近年来,深共熔溶剂热作为一种绿色合成方法被广泛用于多种杂化功能材料的合成。在本研究中,这一合成方法被引入到多核Zr-和Zr/Ti-O纳米团簇的制备,成功获得被邻菲罗啉、苯酚等共轭配体修饰的Zr6以及Ti11Zr4团簇。此方法将为具有精准结构信息的被较多发色团包覆的纳米团簇的合成开辟新的技术路线。此外,光催化分解水产氢实验结果表明,由于具有不同的簇核环境,这两种纳米团簇表现出不同的分散性及与之相关的产氢活性。因此,该研究也为探索金属氧簇材料的结构–性能关系以及结构设计原则提供了借鉴。 相似文献
57.
An isocratic reversed-phase high-performance liquid chromatographic method has been developed for separation and simultaneous determination of COX-2 inhibitors, viz., celecoxib, rofecoxib, valdecoxib, nimesulide and nabumetone, using 4-chloro-2-nitroaniline as internal standard. Good chromatographic separation was achieved using a reversed-phase Inertsil C(18) column with mobile phase consisting of methanol and 0.05% aqueous glacial acetic acid (68:32 v/v) using photodiode array (PDA) detector at 230 nm. It was validated with respect to accuracy, precision, linearity, limit of detection and quantification. The linearity range was found to be 1.0--20 microg/mL and the percentage recoveries were between 97.55 and 100.14. The method is suitable not only for the estimation of active ingredients in pharmaceutical dosage forms but also in vitro estimations in human plasma. It is simple, rapid, selective and capable of detecting and determining COX-2 inhibitors with a detection limit of 0.127--1.040 microg/mL simultaneously. 相似文献
58.
Nagaraju Barsu Deepti Kalsi Prof. Basker Sundararaju 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(26):9364-9368
A one‐step synthetic method was developed for allylation of benzamides using Ni(COD)2/RCO2H and [Ni(μ‐H2O)(OOCCMe3)2(HOOCCMe3)2]2 ( A′ ) catalytic system. Efficient, well‐defined, air and moisture‐stable Ni–pivalate complex was isolated and employed in catalytic allylation. The influence of solvent on product selectivity was also investigated. 相似文献
59.
Chaithra Nagaraju Swarup Hassan Ashok Sadashivamurthy Shamanth Sandhya C. Nagarakere Makanahalli P. Sunilkumar 《合成通讯》2020,50(17):2647-2654
Abstract A facile and conveniently simple new protocol is devised for the synthesis of 3,5-disubstituted and annulated isothiozoles under transition metal and catalyst free conditions utilizing easily available acetophenones, dithioesters and NH4OAc. This strategy involves C=O and C=S functionalization via sequential imine formation followed by intra molecular cyclization and aerial oxidation forming consecutive C?N and S?N bonds respectively in one pot. This protocol offers a low cost, user friendly, straight forward and widely applicable approach to 3,5-disubstituted isothiazoles. 相似文献
60.
Manjunath Giridhar Halehatty S. Bhojya Naik Chatnalli N. Sudhamani Mustur C. Prabakara Rajappa Kenchappa Nagaraju Venugopal Sameer Patil 《中国化学会会志》2020,67(2):316-323
ZnO nanoparticles were successfully synthesized using a microwave method, whose surface was modified with {4-[(E)-2-(furan-2-yl)ethenyl]pyridin-1-ium-1-yl}acetate as a capping agent (1 and 3%). Their structural properties were investigated using FTIR, XRD, SEM, EDS, and UV–visible spectroscopy. XRD confirmed the Wurtzite structure for all compounds, a size of 30.6 nm for uncapped and 22.9 nm for 3% dye-capped nanoparticles were calculated from Scherer's equation. Hexagonal wurtzite shape of nanoparticles can be clearly seen in the SEM images. The DFT calculations were carried out using quantum espresso. These dye-capped ZnO nanoparticles were proved to be potential antibacterial agents, the minimum concentrations of dye-capped ZnO nanoparticles that inhibit the growth of bacteria are 1.5 mg/mL for Escherichia coli and 0.78 mg/mL for Bacillus subtilis, which are much lower than those of uncapped ZnO. The bioactivity data suggest these organic–inorganic hybrid nanoparticles emerged as a new class of antibacterial agents. 相似文献