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51.
Prashant Thakare Abhijit Shinde Sagar Dakhane Abhijit Chavan Vivek D. Bobade Pravin C. Mhaske 《Journal of heterocyclic chemistry》2021,58(9):1867-1877
Cyclocondensation reaction of 4-(2-bromoacetyl)quinolin-1-ium bromide ( 4a–d ) with substituted arylthiourea, ( 5a–g ) afforded 4-(6-substituted quinolin-4-yl)-N-aryl/pyridyl thiazol-2-amine ( 6a-ab ). These newly synthesized derivatives were evaluated for in vitro antibacterial activity against Escherichia coli (NCIM 2574), Proteus mirabilis (NCIM 2388) (Gram-negative strains), Bacillus subtilis (NCIM 2063), Staphylococcus albus (NCIM 2178) (Gram-positive strains) and in vitro antifungal activity against Aspergillus niger (ATCC 504) and Candida albicans (NCIM 3100). Compounds 6a , 6b , 6d , 6f , 6k , and 6l showed moderate to good antibacterial activity against S. albus. Ten derivatives 6c , 6q , 6r , 6s , 6t , 6v , 6w , 6x , 6y , and 6aa , showed moderate to good activity against A. niger. N-[4-(Quinolin-4-yl)-1,3-thiazol-2-yl]pyridin-2-amine presented comparable activity against A. niger with respect to standard drug Rouconazole. 相似文献
52.
Dattatraya N. Bhangare Rohit G. Shinde Pushpalata D. Pawar Milind D. Nikalje Mahendra N. Lokhande 《Journal of heterocyclic chemistry》2021,58(9):1878-1882
This method involves the direct asymmetric aldol reaction of (−)-menthyl isothiocyanatoacetate 5 with a variety of substituted aromatic aldehydes, which offers a convenient method for the synthesis of intermediate containing biologically relevant α-amino β-hydroxyl groups in oxazolidine ring. In this methodology, the products show remarkable diastereoselectivity using Sc(OTf)3 as a catalyst and easily accessible (−)-menthol as a chiral auxiliary. This approach includes some important aspects such as mild reaction conditions, high yields, and excellent diastereoselectivity with a number of substituted aromatic aldehydes. The optimization and effect of different catalysts were studied at different reaction conditions and it is found that Sc(OTf)3 shows excellent diastereoselectivity at −45°C. 相似文献
53.
Darolia Poonam Jangra Malik Sunita Sharma Dimple Kumar Manish Garg Sapana Sharma V. K. 《Journal of solution chemistry》2021,50(11-12):1391-1431
Journal of Solution Chemistry - Excess molar volumes, $$V_{{}}^{{\text{E}}}$$ , excess isentropic compressibilities, $$\kappa_{{\text{S}}}^{{\text{E}}}$$ of binary 1-butyl-2,3-dimethylimidazolium... 相似文献
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Reka Geczy Niels Johan Christensen Kim K. Rasmussen Ildik Klomista Manish K. Tiwari Pratik Shah Seong Wook Yang Morten J. Bjerrum Peter W. Thulstrup 《Angewandte Chemie (International ed. in English)》2020,59(37):16091-16097
Fluorescent, DNA‐stabilized silver nanoclusters (DNA‐AgNCs) are applied in a range of applications within nanoscience and nanotechnology. However, their diverse optical properties, mechanism of formation, and aspects of their composition remain unexplored, making the rational design of nanocluster probes challenging. Herein, a synthetic procedure is described for obtaining a high yield of emissive DNA‐AgNCs with a C‐loop hairpin DNA sequence, with subsequent purification by size‐exclusion chromatography (SEC). Through a combination of optical spectroscopy, gel electrophoresis, inductively coupled plasma mass spectrometry (ICP‐MS), and small‐angle X‐ray scattering (SAXS) in conjunction with the systematic study of various DNA sequences, the low‐resolution structure and mechanism of the formation of AgNCs were investigated. Data indicate that fluorescent DNA‐AgNCs self‐assemble by a head‐to‐head binding of two DNA hairpins, bridged by a silver nanocluster, resulting in the modelling of a dimeric structure harboring an Ag12 cluster. 相似文献
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Laboratory formation of four isomers of C5H2 molecule is reported and detection of the ring-chain isomer (isomer 1) of C5H2 in cosmic objects has been suggested. For identification of a molecule in cosmic objects, one of the required input data
is EinsteinA-coefficients (radiative transition probabilities) for the molecule. Here, we report EinsteinA-coefficients for electric dipole transitions in the ring-chain isomer of C5H2 among the rotational levels of the ground electronic and ground vibrational states up to 21 cm−1. 相似文献
59.
Zhao T Shinde SR Ogale SB Zheng H Venkatesan T Ramesh R Das Sarma S 《Physical review letters》2005,94(12):126601
An external electric field induced reversible modulation of a room temperature magnetic moment and coercive field is achieved in an epitaxial and insulating thin film of dilutely cobalt-doped anatase TiO2. This first demonstration of an electric field effect in any oxide-based diluted ferromagnet is realized in a high quality epitaxial heterostructure of PbZr(0.2)Ti(0.8)O(3)/Co: TiO(2)/SrRuO(3) grown on (001) LaAlO3. The observed effect, which is about 15% in strength in a given heterostructure, can be modulated over several cycles. Possible mechanisms for electric field induced modulation of insulating ferromagnetism are discussed. 相似文献
60.
[reaction: see text] The photoinduced o-benzannulation of 3-(2-vinyl)indolylcarbene complexes provides a direct route to carbazole derivatives that are oxygenated in the 3- and 4-positions. This reaction is quite efficient and provides for a unique synthesis of the lipid peroxidation inhibitor carbazoquinocin C. 相似文献