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71.
Chita Ranjan Sahoo Jyotirmaya Sahoo Monalisa Mahapatra Debananda Lenka Pratap Kumar Sahu Budheswar Dehury Rabindra Nath Padhy Sudhir Kumar Paidesetty 《Arabian Journal of Chemistry》2021,14(2):102922
Nowadays, bacterial infections epitomize significant health threats globally with an increased morbidity and mortality. Most contemporary antibacterial agents are resisted by pathogenic bacteria - the multidrug resistant (MDR) bacterial strains arising from cross resistances operative in natural bacterial consortia inside human body and in environments. Consequently, the development of newer potential drug candidate(s) is required against the broad spectrum of MDR bacteria. Indeed, the phytochemical coumarin and its derivatives had been reported with broad biological inhibitory properties, including antibacterial activities. In this review, several methods of synthetic strategies of coumarin derivatives as antibacterials were considered with individual schematic compounds by structure-activity relationship (SAR) studies as essential corollaries. Overall, substituents at positions C-3 and C-4 of coumarin are coveted for the development of newer antibacterial agents. 相似文献
72.
Jalpa C. Trivedi Kuldip D. Upadhyay Sudhir K. Joshi Erik De Clercq 《Tetrahedron letters》2007,48(48):8472-8474
Two closely structurally related coumarins, 4-hydroxy-8-isopropyl-5-methylcoumarin and 4-hydroxy-6-chloro-7-methylcoumarin were acylated at C-3 and further converted to the respective chalcones and two series of eighteen new compounds, which were evaluated for possible antiviral activity. 相似文献
73.
Hert DG Anderson JL Aki SN Brennecke JF 《Chemical communications (Cambridge, England)》2005,(20):2603-2605
The presence of CO(2) increases the solubility of O(2) and CH(4) in 1-hexyl-3-methylimidazolium bis(trifluoromethylsulfonyl) imide at 25 degrees C and pressures to 13 bar. 相似文献
74.
Densities and viscosities have been determined for binary mixtures of isopropyl acetate or isobutyl acetate with o-xylene, m-xylene, p-xylene and ethyl benzene at (303.15 and 313.15) K for the entire composition range. The excess molar volumes and deviations
in viscosity have been calculated from the experimental values. The variations of these parameters, with composition of the
mixtures and temperature, have been discussed in terms of molecular interactions occurring in these mixtures. Further, the
viscosities of these binary mixtures were calculated theoretically from their corresponding pure component data by using empirical
relations, and the results were compared with the experimental findings. 相似文献
75.
JPC – Journal of Planar Chromatography – Modern TLC - 相似文献
76.
A total synthesis of ageladine A has been achieved by exploiting a Pictet-Spengler-type condensation between 2-aminohistamine and 4,5-dibromo-2-formylpyrrole as the key step. 相似文献
77.
Husale BS Sahoo S Radenovic A Traversi F Annibale P Kis A 《Langmuir : the ACS journal of surfaces and colloids》2010,26(23):18078-18082
We used AFM to investigate the interaction of polyelectrolytes such as ssDNA and dsDNA molecules with graphene as a substrate. Graphene is an appropriate substrate due to its planarity, relatively large surfaces that are detectable via an optical microscope, and straightforward identification of the number of layers. We observe that in the absence of the screening ions deposited ssDNA will bind only to the graphene and not to the SiO(2) substrate, confirming that the binding energy is mainly due to the π-π stacking interaction. Furthermore, deposited ssDNA will map the graphene underlying structure. We also quantify the π-π stacking interaction by correlating the amount of deposited DNA with the graphene layer thickness. Our findings agree with reported electrostatic force microscopy (EFM) measurements. Finally, we inspected the suitability of using a graphene as a substrate for DNA origami-based nanostructures. 相似文献
78.
P. Shanmugavadivu V. Sivakumar Rashmi Sudhir 《The European physical journal. Special topics》2016,225(1):137-146
A new Fractal Dimension-based diagnosis technique for the change detection and time-series analysis of masses in the temporal digital mammogram is presented in this paper. As the digital mammograms are confirmed as a reliable source for the prognosis of breast cancer, the demand for the development of precise computer aided detection techniques is constantly on the increase. This formed the basis for the development of this method using Fractal geometry, which is an efficient mathematical approach that deals with self-similar and irregular geometric objects called fractals. This work comprises of the detection of spatial masses using Fractal Hurst bound enhancement and segmentation of those temporal masses using Fractal Thresholding. The consultant radiologist’s assessment of mass lesions forms the baseline for comparison and validation of the detected masses. Further, this research work performs temporal analysis of mass lesions, detected from the mammograms of the current and the respective prior view using the principle of Fractal Dimension. The precision of Fractal-dimension based temporal texture analysis of malignant masses of digital mammograms subsequently attributes to their characterization. 相似文献
79.
Sudhir Hande Adelphe Mfuh Scott Throner Ye Wu Qing Ye XiaoLan Zheng 《Tetrahedron letters》2019,60(41):151100
A new photoredox-catalyzed CN coupling reaction of sulfoximines with aryl halides has been developed for a general N-arylation of sulfoximines. The reactions proceed in the presence of visible light with high levels of chemoselectivity and a wide range of functionality is tolerated. There is a rapidly increasing interest in sulfoximines as pharmacophores in drug discovery and this new method offers potential in terms of high functional group tolerance and late-stage functionalization of compounds. 相似文献
80.
Facile synthesis of a number of 1,7,7-trimethyl -3-(E-2′-arylethenyl)-2-oxabicyclo [4.4.0] deca-3, 5-dienes, through UV irradiation of (E/E) -arylidene-β-ionones, is described. 相似文献