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991.
992.
Ranjit Kulkarni Jieyang Huang Matthias Trunk David Burmeister Patrick Amsalem Johannes Müller Andra Martin Norbert Koch Dustin Kass Michael J. Bojdys 《Chemical science》2021,12(38):12661
Graphdiyne polymers have interesting electronic properties due to their π-conjugated structure and modular composition. Most of the known synthetic pathways for graphdiyne polymers yield amorphous solids because the irreversible formation of carbon–carbon bonds proceeds under kinetic control and because of defects introduced by the inherent chemical lability of terminal alkyne bonds in the monomers. Here, we present a one-pot surface-assisted deprotection/polymerisation protocol for the synthesis of crystalline graphdiynes over a copper surface starting with stable trimethylsilylated alkyne monomers. In comparison to conventional polymerisation protocols, our method yields large-area crystalline thin graphdiyne films and, at the same time, minimises detrimental effects on the monomers like oxidation or cyclotrimerisation side reactions typically associated with terminal alkynes. A detailed study of the reaction mechanism reveals that the deprotection and polymerisation of the monomer is promoted by Cu(ii) oxide/hydroxide species on the as-received copper surface. These findings pave the way for the scalable synthesis of crystalline graphdiyne-based materials as cohesive thin films.We present a one-pot deprotection/polymerisation protocol for the synthesis of crystalline graphdiynes on top of a copper surface starting with stable trimethylsilylated alkyne monomers. 相似文献
993.
Deka Jyoti Prasad Sarma Amarendra K. Govindarajan A. Kulkarni Manas 《Nonlinear dynamics》2020,100(2):1629-1640
Nonlinear Dynamics - We propose a generalized parity-time ($$\mathcal {PT}$$)-symmetric Liénard oscillator with two different orders of nonlinear position-dependent dissipation. We study the... 相似文献
994.
Ibrahim Ahmed Shaikh Uday M. Muddapur Krithika C Shrikanth Badiger Madhura Kulkarni Mater H. Mahnashi Saleh A. Alshamrani Mohammed A. Huneif Sunil S. More Aejaz Abdullatif Khan S. M. Shakeel Iqubal 《Molecules (Basel, Switzerland)》2022,27(5)
Current drug discovery involves finding leading drug candidates for further development. New scientific approaches include molecular docking, ADMET studies, and molecular dynamic simulation to determine targets and lead compounds. Hepatitis B is a disease of concern that is a life-threatening liver infection. The protein considered for the study was HBx. The hepatitis B X-interacting protein crystal structure was obtained from the PDB database (PDB ID-3MSH). Twenty ligands were chosen from the PubChem database for further in silico studies. The present study focused on in silico molecular docking studies using iGEMDOCK. The triethylene glycol monoethyl ether derivative showed an optimum binding affinity with the molecular target HBx, with a high negative affinity binding energy of −59.02 kcal/mol. Lipinski’s rule of five, Veber, and Ghose were followed in subsequent ADMET studies. Molecular dynamic simulation was performed to confirm the docking studies and to analyze the stability of the structure. In these respects, the triethylene glycol monoethyl ether derivative may be a promising molecule to prepare future hepatitis B drug candidates. Substantial research effort to find a promising drug for hepatitis B is warranted in the future. 相似文献
995.
P.G. Siddheshwar B.S. Bhadauria Pankaj Mishra Atul K. Srivastava 《International Journal of Non》2012,47(5):418-425
The present paper deals with a weak non-linear stability problem of magneto-convection in an electrically conducting Newtonian fluid, confined between two horizontal surfaces, under a constant vertical magnetic field, and subjected to an imposed time-periodic boundary temperature (ITBT) or gravity modulation (ITGM). In the case of ITBT, the temperature gradient between the walls of the fluid layer consists of a steady part and a time-dependent oscillatory part. The temperature of both walls is modulated in this case. In the problem involving ITGM, the gravity field has two parts: a constant part and an externally imposed time periodic part, which can be realized by oscillating the fluid layer. The disturbance is expanded in terms of power series of amplitude of convection, which is assumed to be small. Using Ginzburg–Landau equation, the effect of modulations on heat transport is analyzed. Effect of various parameters on the heat transport is also discussed. 相似文献
996.
Yamuna Krishnan-Ghosh R. Srinivasa Gopalan G. U. Kulkarni Santanu Bhattacharya 《Journal of Molecular Structure》2001,560(1-3):345-355
Cholest-5-en-3β-oxy-5-bromopentane (1) and cholest-5-en-3β-oxy-11-bromoundecane (2), key precursors for the synthesis of novel cationic amphiphiles based on cholesterol, have been synthesized and characterized by 1H-NMR spectroscopy and X-ray crystallography. Thermal disorder and effect of length of the bromoalkyl segment on the crystal structure have been investigated. Possible molecular level explanation of the unusual alternating s-trans–gauche conformation of the bromopentyl side chain of (1) has been presented. 相似文献
997.
Nigel Vicker Helen V. Bailey Joanna M. Day Mary F. Mahon Andrew Smith Helena J. Tutill Atul Purohit Barry V. L. Potter 《Molecules (Basel, Switzerland)》2021,26(23)
17β-Hydroxysteroid dehydrogenase type 3 (17β-HSD3) is expressed at high levels in testes and seminal vesicles; it is also present in prostate tissue and involved in gonadal and non-gonadal testosterone biosynthesis. The enzyme is membrane-bound, and a crystal structure is not yet available. Selective aryl benzylamine-based inhibitors were designed and synthesised as potential agents for prostate cancer therapeutics through structure-based design, using a previously built homology model with docking studies. Potent, selective, low nanomolar IC50 17β-HSD3 inhibitors were discovered using N-(2-([2-(4-chlorophenoxy)phenylamino]methyl)phenyl)acetamide (1). The most potent compounds have IC50 values of approximately 75 nM. Compound 29, N-[2-(1-Acetylpiperidin-4-ylamino)benzyl]-N-[2-(4-chlorophenoxy)phenyl]acetamide, has an IC50 of 76 nM, while compound 30, N-(2-(1-[2-(4-chlorophenoxy)-phenylamino]ethyl)phenyl)acetamide, has an IC50 of 74 nM. Racemic C-allyl derivative 26 (IC50 of 520 nM) was easily formed from 1 in good yield and, to determine binding directionality, its enantiomers were separated by chiral chromatography. Absolute configuration was determined using single crystal X-ray crystallography. Only the S-(+)-enantiomer (32) was active with an IC50 of 370 nM. Binding directionality was predictable through our in silico docking studies, giving confidence to our model. Importantly, all novel inhibitors are selective over the type 2 isozyme of 17β-HSD2 and show <20% inhibition when tested at 10 µM. Lead compounds from this series are worthy of further optimisation and development as inhibitors of testosterone production by 17β-HSD3 and as inhibitors of prostate cancer cell growth. 相似文献
998.
999.
Paul Sabyasachi Joshi D. S. Shanbhag A. A. Sahoo G. S. Tripathy S. P. Sharma S. C. Suman V. Biju K. Bandyopadhyay T. Kulkarni M. S. 《Journal of Radioanalytical and Nuclear Chemistry》2020,323(3):1299-1306
Journal of Radioanalytical and Nuclear Chemistry - Presently accelerator facilities emphasizes on generating charged particles with enhanced energy and flux. The radiation protection practices at... 相似文献
1000.
Pawar Umakant D. Pawar Chandrakant D. Kulkarni Ulka K. Pardeshi Rajendra K. Farooqui Mazahar Shinde Devanand B. 《平面色谱法杂志一现代薄层色谱法》2019,32(1):65-68
JPC – Journal of Planar Chromatography – Modern TLC - 相似文献