668493-38-7Relevant articles and documents
Synthesis and Functional Properties of Strongly Luminescent Diphenylamino End-Capped Oligophenylenes
Li, Zhong Hui,Wong, Man Shing,Tao, Ye,D'Iorio, Marie
, p. 921 - 927 (2007/10/03)
Two novel homologous series of oligophenylenes (OPPs) symmetrically end-capped with diphenylamino groups and asymmetrically end-capped with anthryldiphenylamino groups were successfully synthesized by a convergent approach with use of palladium-catalyzed homo- and cross-coupling of arylboronic acids. The absorption maxima of both diphenylamino end-capped OPP series do not vary with the chain length although the molar absorptivities increase sequentially. On the other hand, the emission maxima slightly shift to longer wavelengths when the phenylene unit increases in the series. All the diphenylamino end-capped oligomers exhibit very large fluorescence quantum yields (81-89%). They also exhibit low first ionization potentials, corresponding to the oxidation of the triarylamino moiety, which are essentially unaffected by the oligomeric length extension. The good thermal stabilities of these oligomers allowed the fabrication of multilayer light-emitting devices and their investigations.
Antileishmanial activities of several classes of aromatic dications
Brendle, James J.,Outlaw, Abram,Kumar, Arvind,Boykin, David W.,Patrick, Donald A.,Tidwell, Richard R.,Werbovetz, Karl A.
, p. 797 - 807 (2007/10/03)
Aromatic dicationic molecules possess impressive activity against a broad spectrum of microbial pathogens, including Pneumocystis carinii, Cryptosporidium parvum, and Candida albicans. In this work, 58 aromatic cations were examined for inhibitory activity against axenic amastigote-like Leishmania donovani parasites. In general, the most potent of the compounds were substituted diphenyl furan and thiophene dications. 2,5-Bis-(4-amidinophenyl)thiophene was the most active compound. This agent displayed a 50% inhibitory concentration (IC50) of 0.42 ± 0.08 μM against L. donovani and an in vitro antileishmanial potency 6.2-fold greater than that of the clinical antileishmanial dication pentamidine and was 155-fold more toxic to the parasites than to a mouse macrophage cell line. 2,4-Bis-(4-amidinopheny)furan was twice as active as pentamidine (IC50, 1.30 ± 0.21 μM), while 2,5-bis-(4-amidinopheny)furan and pentamidine were essentially equipotent in our in vitro antileishmanial assay. Carbazoles, dibenzofurans, dibenzothiophenes, and benzimidazoles containing amidine or substituted amidine groups were generally less active than the diphenyl furans and thiophenes. In all cases, aromatic dications possessing strong antileishmanial activity were severalfold more toxic to the parasites than to a cultured mouse macrophage cell line. These structure-activity relationships demonstrate the potent antileishmanial activity of several aromatic dications and provide valuable information for the future design and synthesis of more potent antiparasitic agents.
Linear Free Energy Relationship Studies of 5-Substituted 2,4-Dioxopyrimidine Nucleosides
Chang, George,Mertes, Mathias P.
, p. 3625 - 3631 (2007/10/02)
The development of a direct and efficient palladium(0)-catalyzed biaryl coupling reaction permitted the synthesis of a series of N1-substituted 5-aryl-2,4-dioxopyrimidines.The physical and spectral properties of these compounds were determined and correlated by various linear free energy relationships.The relationships between the physical and spectral data with Hammett ? constants proved useful in analyzing the electron distribution of the heterocycle.Although a significant degree of orbital overlap and interaction between the substituents and the pyrimidine ring was observed, it is doubtful that the interactions are comparable to those of a benzene ring system.
