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1.
Tapasi Chand Laxmikanta Khamari Deepak Chopra Saptarshi Mukherjee Manmohan Kapur 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(43):e202200723
A one-step Rh-catalyzed site-selective ortho-C−H alkynylation of perylene as well as naphthalene mono- and diimides is reported. A single step regioselective access to ortho-C−H alkynylated derivatives of these ryleneimides not only increases the step economy of the ortho-functionalization on these dyes but also provides a quick access route towards highly functionalized dyes that have potential optoelectronic applications. Increased solubility of tetra(triisopropylsilyl)acetylenyl PDIs in organic solvents greatly enhances their utility for further derivatization. 相似文献
2.
Dinesh R. Hussain S. Imran Roseline A. Ameelia Kalaiselvam S. 《Journal of Thermal Analysis and Calorimetry》2021,145(6):2935-2949
Journal of Thermal Analysis and Calorimetry - In this paper, the variation of thermophysical properties such as the thermal conductivity, thermal energy storage capacity, viscosity, and phase... 相似文献
3.
The serine protease, DegP exhibits proteolytic and chaperone activities, essential for cellular protein quality control and normal cell development in eukaryotes. The P. falciparum DegP is essential for the parasite survival and required to combat the oscillating thermal stress conditions during the infection, protein quality checks and protein homeostasis in the extra-cytoplasmic compartments, thereby establishing it as a potential target for drug development against malaria. Previous studies have shown that diisopropyl fluorophosphate (DFP) and the peptide SPMFKGV inhibit E. coli DegP protease activity. To identify novel potential inhibitors specific to PfDegP allosteric and the catalytic binding sites, we performed a high throughput in silico screening using Malaria Box, Pathogen Box, Maybridge library, ChEMBL library and the library of FDA approved compounds. The screening helped identify five best binders that showed high affinity to PfDegP allosteric (T0873, T2823, T2801, , CD00811) and the catalytic binding site (T0078L, T1524, T2328, BTB11534 and 552691). Further, molecular dynamics simulation analysis revealed RJC02337, BTB11534 as the best hits forming a stable complex. WaterMap and electrostatic complementarity were used to evaluate the novel bio-isosteric chemotypes of RJC02337, that led to the identification of 231 chemotypes that exhibited better binding affinity. Further analysis of the top 5 chemotypes, based on better binding affinity, revealed that the addition of electron donors like nitrogen and sulphur to the side chains of butanoate group are more favoured than the backbone of butanoate group. In a nutshell, the present study helps identify novel, potent and Plasmodium specific inhibitors, using high throughput in silico screening and bio-isosteric replacement, which may be experimentally validated. RJC02337相似文献
4.
Chandrachood Pranav S. Jadhav Amol R. Garud Dinesh R. Deshpande Nirmala R. Puranik Vedavati G. Kashalkar Rajashree V. 《Research on Chemical Intermediates》2020,46(12):5219-5230
Research on Chemical Intermediates - A series of quinoxaline derivatives were efficiently synthesized by convenient and simple procedure in excellent yields using 1 wt.% of titanium silicate (TS-1)... 相似文献
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Several new families of c‐Bhaskar Rao designs with block size 4 are constructed. The necessary conditions for the existence of a c‐BRD (υ,4,λ) are that: (1)λmin=?λ/3 ≤ c ≤ λ and (2a) c≡λ (mod 2), if υ > 4 or (2b) c≡ λ (mod 4), if υ = 4 or (2c) c≠ λ ? 2, if υ = 5. It is proved that these conditions are necessary, and are sufficient for most pairs of c and λ; in particular, they are sufficient whenever λ?c ≠ 2 for c > 0 and whenever c ? λmin≠ 2 for c < 0. For c < 0, the necessary conditions are sufficient for υ> 101; for the classic Bhaskar Rao designs, i.e., c = 0, we show the necessary conditions are sufficient with the possible exception of 0‐BRD (υ,4,2)'s for υ≡ 4 (mod 6). © 2002 Wiley Periodicals, Inc. J Combin Designs 10: 361–386, 2002; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/jcd.10009 相似文献
7.
Prashant M. Bhatt Gautam R. Desiraju 《Acta Crystallographica. Section C, Structural Chemistry》2006,62(6):o362-o363
The title compound [systematic name: 8‐chloro‐11‐(piperidin‐4‐ylidene)‐6,11‐dihydro‐5H‐benzo[4,5]cyclohepta[2,1‐b]pyridine], C19H19ClN2, was crystallized from ethyl acetate. The interesting feature of the reported structure is that it does not contain any strong hydrogen bonds, although the molecule contains a secondary NH group, which is a good hydrogen‐bond donor. 相似文献
8.
Morey Timothy E. Varshney Manoj Flint Jason A. Seubert Christoph N. Smith W. Brit Bjoraker David G. Shah Dinesh O. Dennis Donn M. 《Journal of nanoparticle research》2004,6(2):159-170
Background: Although microemulsion-based nanoparticles (MEs) may be useful for drug delivery or scavenging, these benefits must be balanced against potential nanotoxicological effects in biological tissue (bio-nano interface). We investigated the actions of assembled MEs and their individual components at the bio-nano interface of thrombosis and hemolysis in human blood.
Methods: Oil-in-water MEs were synthesized using ethylbutyrate, sodium caprylate, and pluronic F-68 (ME4) or F-127 (ME6) in 0.9% NaClw/v. The effects of MEs or components on thrombosis were determined using thrombo-elastography, platelet contractile force, clot elastic modulus, and platelet counting. For hemolysis, ME or components were incubated with erythrocytes, centrifuged, and washed for measurement of free hemoglobin by spectroscopy.
Results and conclusions: The mean particle diameters (polydispersity index) for ME6 and ME4 were 23.6 ± 2.5 nm (0.362) and 14.0 ± 1.0 nm (0.008), respectively. MEs (0, 0.03, 0.3, 3 mM) markedly reduced the thromboelastograph maximal amplitude in a concentration-dependent manner (49.0 ± 4.2, 39.0 ± 5.6, 15.0 ± 8.7, 3.8 ± 1.3 mm, respectively), an effect highly correlated (r2 = 0.94) with similar changes caused by pluronic surfactants (48.7 ± 10.9, 30.7 ± 15.8, 20.0 ± 11.3, 2.0 ± 0.5) alone. Neither oil nor sodium caprylate alone affected the thromboelastograph. The clot contractile force was reduced by ME (27.3 ± 11.1–6.7 ± 3.4 kdynes/cm2, P = 0.02, n = 5) whereas the platelet population not affected (175 ± 28–182 ± 23 106/ml, P = 0.12, n = 6). This data suggests that MEs reduced platelet activity due to associated pluronic surfactants, but caused minimal changes in protein function necessary for coagulation. Although pharmacological concentrations of sodium caprylate caused hemolysis (EC50 = 213 mM), MEs and pluronic surfactants did not disrupt erythrocytes. Knowledge of nanoparticle activity and potential associated nanotoxicity at this bio-nano interface enables rational ME design for in vivo applications. 相似文献
9.
Raviraj M Kulkarni Dinesh C Bilehal Sharanappa T Nandibewoor 《Analytical sciences》2004,20(4):743-747
The kinetics of oxidation of isoniazid in acidic medium was studied spectrophotometrically. The reaction between QDC and isoniazid in acid medium exhibits (4:1) stoichiometry (QDC:isoniazid). The reaction showed first order kinetics in quinolinium dichromate (QDC) concentration and an order of less than unity in isoniazid (INH) and acid concentrations. The oxidation reaction proceeds via a protonated QDC species, which forms a complex with isoniazid. The latter decomposes in a slow step to give a free radical derived from isoniazid and an intermediate chromium(V), which is followed, by subsequent fast steps to give the products. The reaction constants involved in the mechanism are evaluated. Isoniazid was analyzed by kinetic methods in pure and pharmaceutical formulations. 相似文献
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