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61.
Premanand Ramrao Patil K. P. Ravindranathan Kartha 《Journal of carbohydrate chemistry》2013,32(7):411-419
Aryl glycosides have been prepared from a range of readily available glycosyl halides by a solvent-free mechanochemical procedure employing a planetary ball mill in excellent yields. Besides being a solvent-free reaction, the procedure has been successful in eliminating the need for employing any phase-transfer catalyst in the reaction. 相似文献
62.
seco-Iso-cyclopropylfurano[e]indoline-trimethoxyindole 1 and seco-cyclopropylfurano[f]quinoline-trimethoxyindole 2 are potent cytotoxic agents. Previous synthesis of these compounds was inefficient and the approach required separation of a mixture containing the isomeric indoline and quinoline intermediates 11 and 12, formed from radical cyclization of allylic bromide 10. Reported herein is an efficient and selective synthesis of either intermediate 11 or 12, thus product 1 or 2, as needed. The conditions of the Stobbe condensation, bromination, 5-exo-trig radical cyclization, amine-carboxylic acid coupling, and debenzylation were optimized for multi gram scale. As a result, the reaction times were shortened, the products were readily isolated, and the yields and purity improved. 相似文献
63.
A simple method for the preparation of enantiopure furo[2,3-b]pyrroles, a rare class of concave bicyclic nitrogen and oxygen heterocycle, in promising yield has been developed. The 3-substituted pyrrolidinediones prepared from (2S,3S)-tetrahydro-3-hydroxy-5-oxo-2,3-furandicarboxylic acid (Garcinia acid) have been cyclized diastereo as well as enantioselectively to furo[2,3-b]pyrroles. The cyclization follows Baldwin’s rule. 相似文献
64.
Divya Kumar Vemuri Rambabu Gundla Naresh Konduru Ravindra Mallavarapu Naresh Kumar Katari 《Biomedical chromatography : BMC》2022,36(6):e5363
Favipiravir finished dosage was approved for emergency use in many countries to treat SARS-CoV-2 patients. A specific, accurate, linear, robust, simple, and stability-indicating HPLC method was developed and validated for the determination of degradation impurities present in favipiravir film-coated tablets. The separation of all impurities was achieved from the stationary phase (Inert sustain AQ-C18, 250 × 4.6 mm, 5-μm particle) and mobile phase. Mobile phase A contained KH2PO4 buffer (pH 2.5 ± 0.05) and acetonitrile in the ratio of 98:2 (v/v), and mobile phase B contained water and acetonitrile in the ratio of 50:50 (v/v). The chromatographic conditions were optimized as follows: flow rate, 0.7 mL/min; UV detection, 210 nm; injection volume, 20 μL; and column temperature, 33°C. The proposed method was validated per the current International Conference on Harmonization Q2 (R1) guidelines. The recovery study and linearity ranges were established from the limit of quantification to 150% optimal concentrations. The method validation results were found to be between 98.6 and 106.2% for recovery and r2 = 0.9995–0.9999 for linearity of all identified impurities. The method precision results were achieved below 5% of relative standard deviation. Forced degradation studies were performed in chemical and physical stress conditions. The compound was sensitive to chemical stress conditions. During the study, the analyte degraded and converted to unknown degradation impurities, and its molecular mass was found using the LC–MS technique and established degradation pathways supported by reaction of mechanism. The developed method was found to be suitable for routine analysis of research and development and quality control. 相似文献
65.
R.B. Shinde N.S. Padalkar S.V. Sadavar A.S. Patil S.B. Kale V.V. Magdum Y.M. Chitare S.P. Kulkarni U.M. Patil V.G. Parale J.L. Gunjakar 《Materials Today Chemistry》2022
Tuning the interior chemical composition of layered double hydroxides (LDHs) via lattice engineering route is a unique approach to enable multifunctional applications of LDHs. In this regard, the exfoliated 2D LDH nanosheets coupled with various guest species lead to the lattice-engineered LDH-based multifunctional self-assembly with precisely tuned chemical composition. This article reports the synthesis and characterization of mesoporous zinc–chromium-LDH (ZC-LDH) hybridized with isopolyoxovanadate nanohybrids (ZCiV) via lattice-engineered self-assembly between delaminated ZC-LDH nanosheets and isopolyoxovanadate (iPOV) anions. Electrostatic self-assembly between 2D ZC-LDH monolayers and 0D iPOV significantly altered structural, morphological, and surface properties of ZC-LDH. The structural and morphological study demonstrated the formation of mesoporous interconnected sheet-like architectures composed of restacked ZCiV nanosheets with expanded surface area and interlayer spacing. In addition, the ZCiV nanohybrid resistive elements were used as a room-temperature gas sensor. The selectivity of ZCiV nanohybrid was tested for various oxidizing (SO2, Cl2, and NO2) gases and reducing (LPG, CO, H2, H2S, and NH3) gases. The optimized ZCiV nanohybrid demonstrated highly selective SO2 detection with the maximum SO2 response (72%), the fast response time (20 s), low detection limit (0.1 ppm), and long-term stability at room temperature (27 ± 2 °C). Of prime importance, ZCiV nanohybrids exhibited moderately affected SO2 sensing responses with high relative humidity conditions (80%–95%). The outstanding SO2 sensing performance of ZCiV is attributed to the active surface gas adsorptive sites via plenty of mesopores induced by a unique lattice-engineered interconnected sheet-like microstructure and expanded interlayer spacing. 相似文献
66.
Mane Vikas J. Kale Shital B. Ubale Shivaji B. Lokhande Vaibhav C. Patil Umakant M. Lokhande Chandrkant D. 《Journal of Solid State Electrochemistry》2021,25(6):1775-1788
Journal of Solid State Electrochemistry - In this study, the lanthanum sulfide-manganese sulfide (La2S3-MnS) nanosheet composite films with different thicknesses were grown on graphene oxide (GO)... 相似文献
67.
Vijayakumar Sekar González-Sánchez Zaira I. Malaikozhundan Balasubramanian Saravanakumar Kandasamy Divya Mani Vaseeharan Baskaralingam Durán-Lara Esteban F. Wang Myeong-Hyeon 《Journal of Cluster Science》2021,32(5):1129-1139
Journal of Cluster Science - Metal oxide nanoparticles (NPs) have gained attention in biomedicine due to their broad spectrum of applications, such as targeted drug delivery, their use as... 相似文献
68.
Pawar Arvind Gajare Shivanand Patil Audumbar Kurane Rajanikant Rashinkar Gajanan Patil Suresh 《Research on Chemical Intermediates》2021,47(7):2801-2820
Research on Chemical Intermediates - Magnetic separable nanoparticles-decorated N-heterocyclic carbene complex with copper (MNP[1-Methyl benzimidazole]NHC@Cu) has been prepared by covalent grafting... 相似文献
69.
F. M. Sannaningannavar Shivaram N. Patil B. S. Navati R. M. Melavanki N. H. Ayachit 《Journal of Thermal Analysis and Calorimetry》2014,115(2):1813-1820
Dilatometric studies of solutions of four different mole fractions of poly(ethylene glycol) of average molecular mass 400 g mol?1 dissolved in benzene have been performed to estimate molar volumes (V) and volume expansion coefficients (α) at different temperatures. From these, thermodynamic parameters appropriate to these solutions have been evaluated at different temperatures ranging from 299 to 328 K. These parameters have been employed to collect and discuss the information on molecular structure, molecular order, molecular packing, polymer segment extension, and molecular interactions. 相似文献
70.
Anitha Kumary Vidyadharan Divya Jayan T. E. Mary Nancy 《Journal of Solid State Electrochemistry》2014,18(9):2513-2519
A novel electrochemical sensor based on nickel-doped cobalt ferrite nanoparticles (Ni0.1Co0.9Fe2O4)-modified glassy carbon electrode (NCF/GCE) was presented for the sensitive detection of paracetamol. Experimental conditions such as pH, applied potentials and concentration were investigated using cyclic voltammetric and chronoamperometric techniques. The modified electrode exhibited excellent catalytic response towards the oxidation of paracetamol with good reproducibility. The overpotential for oxidation of paracetamol is decreased, and the current response enhanced significantly on the modified electrode in comparison with that of bare electrode. Linear calibration curve is obtained over the range 2 μM to 8,000 μM having a detection limit of 11 nM. The modified electrode facilitated the simultaneous detection of paracetamol, ascorbic acid, and dopamine with good reproducibility. 相似文献