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171.
Ivana Defrenza Alessia Catalano Alessia Carocci Antonio Carrieri Marilena Muraglia Antonio Rosato Filomena Corbo Carlo Franchini 《Journal of heterocyclic chemistry》2015,52(6):1705-1712
Starting from 2‐amino‐1,3‐mercaptobenzothiazoles recently reported ( 1a , 1b , 1c , 1d , 1e , 1f , 1g , 1h ), a series of the corresponding 2‐mercapto‐1,3‐benzothiazole isosters ( 2a , 2b , 2c , 2d , 2e , 2f , 2g , 2h ) were screened for their in vitro antibacterial and antifungal activities. Results underline that the presence of the mercapto moiety at the 2‐position of the heterocyclic nucleus is crucial for activity against bacteria. The biological screening against Candida spp. identified commercial 2f as the most promising compound as antifungal against Candida albicans and tropicalis. Molecular modeling studies supported these results. Then, to enlarge structure‐activity relationship (SAR) studies on series 1 , newly synthesized compounds ( 1k , 1l , 1m , 1n , 1o , 1p ) were reported. All the compounds belonging to this series and bearing a bulky substituent at the 6‐position of the aryl moiety showed high antifungal activity. 相似文献
172.
173.
Cover Picture: Debugging Eukaryotic Genetic Code Expansion for Site‐Specific Click‐PAINT Super‐Resolution Microscopy (Angew. Chem. Int. Ed. 52/2016)
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174.
Petr tpni
ka Ivana Císaov Michal Hor
ek Karel Mach 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(10):1204-1205
The title compound, (η5‐cyclopentadienyl)[(1,2,3,4,5‐η)‐4‐ferrocenyl‐1,2,5,6‐tetrakis(trimethylsilyl)cyclohexa‐2,4‐dien‐1‐yl]titanium(II), [TiFe(C5H5)2(C23H42Si4)] or [Ti{η5‐C6H2{Fe(η5‐C5H4)(η5‐C5H5)}{Si(CH3)3}4}(η5‐C5H5)], possesses two directly linked metallocene units that subtend an angle of 52.9 (1)° (defined by the least‐squares planes of the directly connected π‐ligands) associated with the steric requirements of the bulky trimethylsilyl substituents. The cyclohexadienyl ligand adopts an envelope conformation; the perpendicular distance of its η5‐plane to the Ti atom is 1.512 (1) Å. 相似文献
175.
176.
This paper considers the problem of augmenting a given graph by a cheapest possible set of additional edges in order to make the graph vertex-biconnected. A real-world instance of this problem is the enhancement of an already established computer network to become robust against single node failures. The presented memetic algorithm includes effective preprocessing of problem data and a fast local improvement strategy which is applied before a solution is included into the population. In this way, the memetic algorithm's population consists always of only feasible, locally optimal solution candidates. Empirical results on two sets of test instances indicate the superiority of the new approach over two previous heuristics and an earlier genetic algorithm. 相似文献
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178.
{2‐(N,N‐Dimethylaminomethyl)phenyl}(di‐t‐butyl)tin(IV)chloride, {2‐[(CH3)2NCH2]C6H4}Sn(t‐Bu)2 Cl, has been prepared and characterized using NMR and crystallography. This is the first example of a triorganotin(IV) halide containing the 2‐[(CH3)2NCH2]C6H4—group as a C,N‐chelating ligand with a weak intramolecular Sn—N interaction because of the steric hindrance of t‐butyl groups. The interatomic Sn—N distance is elongated to 2.904(14) Å and the central tin atom is distorted trigonal bipyramidal. Copyright © 2004 John Wiley & Sons, Ltd. 相似文献
179.
Peter Kopčanský Martina Koneracká Milan Timko Ivana Potočová Ladislav Tomčo Natália Tomašovičová Vlasta Závišová Jan Jadzyn 《Journal of magnetism and magnetic materials》2006
The paper presents an overview of the observations of structural transitions in ferronematic based on thermotropic nematic 6CHBT (4-trans-4′-n-hexyl-cyclohexyl-isothiocyanato-benzene) and in ferronematic droplets. The type of anchoring was determined using the results of the capacitance measurements. The ferronematic droplets were observed in solutions of nematogenic 6CHBT with fine magnetic particles and phenyl isocyanate. The phase diagram of the transitions between isotropic and nematic phases was found. The magneto-dielectric measurements of various structural transitions in this new system enabled to estimate the type of anchoring of nematic molecules on magnetic particles surfaces in droplets. 相似文献
180.
Tomislav Došlić Ivica Martinjak Riste Škrekovski Sanja Tipurić Spužević Ivana Zubac 《Journal of mathematical chemistry》2018,56(10):2995-3013
We propose and investigate a new bond-additive structural invariant as a measure of peripherality in graphs. We first determine its extremal values and characterize extremal trees and unicyclic graphs. Then we show how it can be efficiently computed for large classes of chemically interesting graphs using a variant of the cut method introduced by Klav?ar, Gutman and Mohar. Explicit formulas are presented for several classes of benzenoid graphs and Cartesian products. At the end we state several conjectures and list some open problems. 相似文献