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51.
Chitra N. Chandrasekaran S. Srinivas C. Venkata Athmalingam S. Venkatraman B. 《Journal of Radioanalytical and Nuclear Chemistry》2022,331(6):2461-2468
Journal of Radioanalytical and Nuclear Chemistry - In this study, the thoron diffusion characteristic in soil is used as a tool to measure the porosity of the soil. The feasibility is demonstrated... 相似文献
52.
Rituparno Chowdhury Venkata Sai Sreyas Adury Amal Vijay Reman K. Singh Arnab Mukherjee 《化学:亚洲杂志》2021,16(12):1634-1642
Computational drug design is increasingly becoming important with new and unforeseen diseases like COVID-19. In this study, we present a new computational de novo drug design and repurposing method and applied it to find plausible drug candidates for the receptor binding domain (RBD) of SARS-CoV-2 (COVID-19). Our study comprises three steps: atom-by-atom generation of new molecules around a receptor, structural similarity mapping to existing approved and investigational drugs, and validation of their binding strengths to the viral spike proteins based on rigorous all-atom, explicit-water well-tempered metadynamics free energy calculations. By choosing the receptor binding domain of the viral spike protein, we showed that some of our new molecules and some of the repurposable drugs have stronger binding to RBD than hACE2. To validate our approach, we also calculated the free energy of hACE2 and RBD, and found it to be in an excellent agreement with experiments. These pool of drugs will allow strategic repurposing against COVID-19 for a particular prevailing conditions. 相似文献
53.
Satish Gaddam Harshavardhan Reddy Kasireddy Karnakar Konkala Ramesh Katla Nageswar Yadavalli Venkata Durga 《中国化学快报》2014,25(5):732-736
A simple and practical method for the synthesis of N-substituted-2-aminobenzothiazoles via a crosscoupling reaction of 2-iodo anilines with isothiocyanates is envisaged using nano copper oxide as a recyclable catalyst and Cs2CO3as a base in PEG-400,as a bio-degradable,reusable,inexpensive and nontoxic reaction medium,under ligand-free conditions.The present tandem process underlines environmental acceptability to access a wide range of N-substituted-2-aminobenzothiazoles in good to excellent yields. 相似文献
54.
Nishtala Venkata Bharat Mahesh Chityala Bhargavi G. Pasala Vijay Kumar Basavoju Srinivas 《Molecular diversity》2020,24(4):1139-1147
Molecular Diversity - A series of new spirooxindolocarbamates 4a–l and 6a–d were synthesized by using the Betti reaction. All the target compounds were well characterized by IR, NMR and... 相似文献
55.
Metal nanoparticles are nanosized structures that have different potential applications in biological, chemical, medical, and agricultural fields because of their exotic characteristics. Their size ranges from 1 to 100 nm. Metal nanoparticles are either purer forms of metals (eg: Gold, Silver, Copper, Iron, etc.) or their compounds (eg: sulfides, hydroxides, oxides, etc.). Ionic liquids are generally used in the extraction of nanoparticles but they are challenging because of their indigent bio-degradability, bio-compatibility, and sustainability. So Deep Eutectic Solvent (DES) is reported as an alternative to ionic liquids in the formation of nanoparticles. The DESs are a complex of quaternary ammonium salts and hydrogen donors or metal salt. DESs contain higher non-symmetric ions which have lower lattice energy and hence they have a lower melting point. This research utilizes a novel DES (choline chloride – urea) as an effective solvent to produce mercuric sulfide (HgS), zirconium oxide (ZrO), manganese oxide (MnO), and copper oxide (CuO) nanoparticles. As a result, the production of these metal nanoparticles using Choline Chloride (C5H14ClNO) – Urea DES can be treated as a promising way in chemical manufacturing. The nanoparticles have been analyzed using Ultra Violet Spectroscopy, Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM), Fourier Transform Infrared Spectroscopy (FT-IR), X-Ray Diffraction (XRD) and Energy Dispersive X-Ray Analysis (EDAX). 相似文献
56.
Mandipogula Mahesh Veladi Panduranga Girish Prabhu Roopesh Kumar L P. Venkata Ramana 《合成通讯》2017,47(7):716-721
A simple protocol involving metal-free oxidative amidation of benzyl alcohols with amino acid esters has been presented. The amidation proceeds in a radical pathway unlike in conventional metal-mediated extrusion of dihydrogen. The method is advantageous in terms of metal-free conditions, nonexpensive commercial starting substrates. Also various substituents in the starting materials are tolerated and sterically hindered amino acid side chains could provide good yields of amide products. 相似文献
57.
Venkata Reddy Regalla RamaKrishnam Raju Addada Venkat Swami Puli Abhishek S. Saxena Anindita Chatterjee 《Tetrahedron letters》2017,58(24):2344-2346
A short and efficient method for the stereoselective synthesis of Dendrodolide L has been developed from inexpensive and commercially available starting material. This convergent synthesis utilizes Jacobsen kinetic resolution, regioselective ring-opening of epoxide and Yamaguchi macrolactonization as key steps. 相似文献
58.
Desaktivierung von Pd‐Katalysatoren zur Acetoxylierung: direkte Beobachtung durch XPS‐Untersuchungen
59.
60.
Parallel synthesis and high throughput dissolution testing of biodegradable polyanhydride copolymers
Vogel BM Cabral JT Eidelman N Narasimhan B Mallapragada SK 《Journal of combinatorial chemistry》2005,7(6):921-928
We have demonstrated that polycondensation reactions can be carried out in a combinatorial fashion and that the polymer library can be screened at high throughput using a rapid prototyping technique to fabricate multiwell substrates. A linearly varying compositional library of 100 different biodegradable polyanhydride random copolymers that are promising carriers for controlled drug delivery was designed, fabricated, and characterized by IR microscopy within a few hours. The polyanhydride copolymer library was based on 1,6-bis(p-carboxyphenoxy)hexane (CPH) and sebacic anhydride (SA) and was characterized with infrared microspectroscopy to determine the composition within each well. Since degradation and release rates depend on copolymer composition, we also developed new high-throughput methods to investigate drug release from this library of copolymers by designing specific wells for each task. A subset of this library was chosen, and a substrate was designed and fabricated to enable the synthesis and monitoring of dye dissolution from a range of polyanhydride copolymers in a parallel fashion using a CCD camera. Multisample substrates were fabricated with a novel rapid prototyping method that consists of an organic solvent-resistant array of 10 x 10 microwells of 2-muL volume each. The libraries were deposited with a custom-built liquid dispensing system consisting of a series of computer-controlled volume-dispensing pumps and XYZ motion stages. The parallel dye dissolution study displayed a decreasing rate of release with increasing CPH content. This result agrees with previously published data for dye release from poly(CPH-co-SA) copolymers. The methodology described in this work is amenable to numerous applications in the arenas of high-throughput polymer synthesis and characterization. 相似文献