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141.
Murugavel Saminathan Mohan Raj Jayakumar Ravikumar Chandrasekaran Ranganathan Raja Jaabil George Ponnuswamy Alagusundaram 《Journal of heterocyclic chemistry》2021,58(3):841-863
The N-phenylbenzo[g]indazole derivatives, 3-(4-chlorophenyl)-3,3a,4,5-tetrahydro-N-phenylbenzo[g]indazole-2-carbothioamide (4CLPBIC), 3-(4-bromophenyl)-3,3a,4,5-tetrahydro-N-phenylbenzo[g]indazole-2-carbothioamide (4BRPBIC), and 3-(3-bromophenyl)-3,3a,4,5-tetrahydro-N-phenylbenzo[g]indazole-2-carbothioamide (3BRPBIC), were synthesized by the one-pot green amalgamation of solvent-free granulating methodology procedure at room temperature. The synthesized crystals were characterized by single-crystal X-ray diffraction (SC-XRD), FT-IR, FT-Raman, NMR, and UV–Vis techniques. The molecular geometries from XRD experimental values of synthesized compounds 4CLPBIC, 4BRPBIC, and 3BRPBIC in the ground state are compared theoretically by applying the density functional theory (DFT), a method with the B3LYP/6-311G(d,p) basis set using Gaussian 09 software. The vibrational assignments of the synthesized compounds were studied based on potential energy distribution (PED) by the VEDA4 program. The scaled DFT/B3LYP/6-311G(d,p) results show the best agreement with the experimental values. Computational 1H and 13C NMR were acquired by utilizing gauge-independent atomic orbital (GIAO) procedure, and chemical shift results are in good agreement with the experimental values. A web-based theoretical investigation was performed to understand the drug-likeness and ADMET properties of the compounds. Molecular docking studies were carried out against bacterial cholesterol inhibitor block and inhibitor of lanosterol-14α-demethylase CYP51 used in the treatment of topical and systemic mycoses in fungal to understand the inhibitory activity of synthesized compounds. The synthesized molecules were also tested for antibacterial and antifungal activities. 相似文献
142.
The first cubic zinc phosphonate [tBuPO(3)Zn(2-apy)](4) (1) whose core resembles the D4R SBU of zeolites, has been synthesised from a reaction between zinc acetate, tert-butylphosphonic acid and 2-aminopyridine at room temperature; the X-ray structure determination reveals that the molecules of , which crystallise in the tetragonal I4(1)/a space group with crystallographically imposed 4 symmetry, form a 3-D supramolecular assembly aided by N-H...O hydrogen bonding. 相似文献
143.
144.
145.
Murugavel Saminathan Saranya Kanagarajan Ravikumar Chandrasekaran Archana Sivasubramaniyan Ranganathan Raja Ponnusamy Alagusundaram 《中国化学会会志》2020,67(6):1100-1112
Two novel compounds 1-(5-[4-fluorophenyl]-3-phenyl-4,5-dihydro-1H-pyrazol-1-yl)-2-thiocyanatoethanone (FSCN) and 1-(5-[4-chlorophenyl]-3-phenyl-4,5-dihydro-1H-pyrazol-1-yl)-2-thiocyanatoethanone (ClSCN) were synthesized and characterized by SC-XRD, 1H NMR, 13C NMR, FTIR, and UV methods. The X-ray diffraction studies were utilized to prove the 3D crystal structures of FSCN and ClSCN. In both the compounds, the packing is mostly driven by C H⋯N, C H⋯O, and C H⋯π (benzene ring as an acceptor) interactions. In ClSCN, additionally, the π⋯π interaction is observed between the pyrazole ring of one molecule and the benzene ring of the other molecule. The experimental values were compared with the results of DFT/B3LYP/6-311G++(d,p) theoretical computations. The pharmacological screening for FSCN and ClSCN was performed using molinspiration and PreADMET web server. To analyze antibacterial inhibition of the synthesized ligands and Ciprofloxacin (control drug) were interacted with antibacterial protein Thymidylate Kinase (TMK) (PDB ID: 4QGG) with the help of AutoDock Vina tool. The ADMET and docking results of FSCN and ClSCN pointed out the better drug likeness nature and good inhibition behavior with TMK protein. The antibacterial in vitro studies suggested that FSCN compound inhibited well with antibacterial strains than that of ClSCN. The current investigation suggests that with further improvements, our compounds could be preferred as substitute medicine for bacterial diseases. 相似文献
146.
N. Janani S. Ramakumar L. Dhivya C. Deviannapoorani K. Saranya Ramaswamy Murugan 《Ionics》2011,17(7):575-580
Polycrystalline cubic Li7La3Zr2O12 (LLZ) with garnet-related type structure has been synthesized at 700 °C by modified sol–gel processes using citric acid as
organic complexing agent and butan-1-ol or propan-2-ol as surface active agent. Thermal analysis (thermogravimetric/differential
thermal analysis) indicated that the gel must be annealed at around 700 °C to completely remove the organic solvent. X-ray
powder diffraction, X-ray fluorescence, and scanning electron microscopic investigations revealed that Al may not be essential
to form cubic-phase LLZ; however, the addition of Al2O3 led to enhanced sintering of LLZ. 相似文献
147.
Ojas Mahapatra Shivaraman Ramaswamy N. Satya Vijaya Kumar B. Brabu Angeline Littleflower C. Gopalakrishnan 《Colloid Journal》2011,73(5):662-667
Zinc oxide nanostructures were prepared by a simple wet chemical procedure using zinc acetate and sodium hydroxide as precursors.
The process was subjected to quenching treatment and the effect of the treatment on the formation of the nanostructures was
studied using atomic force and scanning electron microscopies. The change in crystal structure of the nanostructures due to
quenching was studied using an X-ray diffractometry that established that physical and structural properties of the nanostructures
were largely influenced by the quenching treatment. 相似文献
148.
Woo M Khan NZ Royce J Mehta U Gagnon B Ramaswamy S Soice N Morelli M Cheng KS 《Journal of chromatography. A》2011,1218(32):5386-5392
A novel anion exchange membrane adsorber is presented which shows excellent impurity removal under different buffer conductivities ranging from 2 to 2 7mS/cm. The membrane utilizes a primary amine ligand (polyallylamine) and was designed specifically to bind impurities at high salt concentrations. Studies with DNA, endotoxin, and virus spiked into buffer at varying salt conditions were done, resulting in clearance of >3, 4, and 4 LRV, respectively, with negligible change on increasing salt up to 27 mS/cm conductivities. Verification of virus removal in mAb feedstocks is also shown. The data are compared with other membrane adsorbers and a conventional resin which utilize traditional chemistries to demonstrate improved purification performance with the primary amine ligand. Additional data on scale-up of the membrane adsorber device is discussed. A stacked flat-sheet design was implemented to ensure linear scale-up of performance using bovine serum albumin (BSA) as a model. The linearly scalable device, coupled with the highly effective membrane for virus, DNA, and endotoxin removal, represents a step forward in polishing technology for the purification of monoclonal antibodies and recombinant proteins. 相似文献
149.
Iyer G Ramaswamy S Asher D Mehta U Leahy A Chung F Cheng KS 《Journal of chromatography. A》2011,1218(26):3973-3981
A method for flow-through purification of viruses and virus like nano-particles using a combination of binding and size-exclusion chromatography was developed. This technique relies on minimizing the external surface area per unit volume available for virus binding by increasing the mean diameter of the beads used in the column. At the same time the impurity binding capacity of the column is maximized by utilizing beads with multiple functionalities of the optimum size. Purification of different types of viruses and virus-like-particles could be achieved using this technique. Flow-through purification of influenza virus using this technique yielded virus recoveries greater than 70-80% coupled with impurity removal greater than 80%. Finally an approach to optimize and facilitate process development using this technology is presented. Since the impurity binding occurs via a non-specific mechanism and virus recovery is achieved through reduced surface area, the technique is not limited to specific types of viruses and offers the potential as a universal purification tool. 相似文献
150.
Maiti M Siegmund V Abramov M Lescrinier E Rosemeyer H Froeyen M Ramaswamy A Ceulemans A Marx A Herdewijn P 《Chemistry (Weinheim an der Bergstrasse, Germany)》2012,18(3):869-879
Orthogonal nucleic acids are chemically modified nucleic acid polymers that are unable to transfer information with natural nucleic acids and thus can be used in synthetic biology to store and transfer genetic information independently. Recently, it was proposed that xylose-DNA (dXNA) can be considered to be a potential candidate for an orthogonal system. Herein, we present the structure in solution and conformational analysis of two self-complementary, fully modified dXNA oligonucleotides, as determined by CD and NMR spectroscopy. These studies are the initial experimental proof of the structural orthogonality of dXNAs. In aqueous solution, dXNA duplexes predominantly form a linear ladderlike (type-1) structure. This is the first example of a furanose nucleic acid that adopts a ladderlike structure. In the presence of salt, an equilibrium exists between two types of duplex form. The corresponding nucleoside triphosphates (dXNTPs) were synthesized and evaluated for their ability to be incorporated into a growing DNA chain by using several natural and mutant DNA polymerases. Despite the structural orthogonality of dXNA, DNA polymerase β mutant is able to incorporate the dXNTPs, showing DNA-dependent dXNA polymerase activity. 相似文献