نتایج جستجو برای: substituted
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Monophenyl-substituted dihydropyrazines (Ph-DHP-1 to 4) of 2,3-dihydro-5,6-dimethylpyrazine (Me-DHP-1), which have the inductive effects of apoptosis and mutagenesis, were synthesized and their biological effect was investigated in terms of DNA strand-breakage. Differences between the phenyl- and methyl-substituted dihydropyrazines were examined.
Cyclopentadienyl, hydrinedienyl, and indenyl glycines were synthesized using dienylaziridines as Nazarov cyclization precursors for the first time. Several substrates were synthesized to demonstrate the compatibility of this reaction. Asymmetric synthesis of these amino acids was also developed to show the additional scope of this method.
Pyridonaphthyridines (triazaphenanthrenes) were prepared in 4 steps and in 13-52% overall yield using Negishi cross-couplings between iodopicolines and 2-chloro-pyridylzinc derivatives. After chlorination, Gabriel amination and spontaneous ring-closure, the final aromatization leading to the triazaphenanthrenes was achieved with chloranil. This heterocyclic scaffold underwent a nucleophilic add...
Recent studies of nuclear spin polarization effects in cyclopropane derivatives have provided considerable information on the structure as well as the spin and charge density distributions in this class of radical ca,tions. In the present work we report an extension of the frontier MO/perturbation MO theory of homoconjugation to include such species in an attempt to rationalize further the expe...
Bright (maximum 11,000 cd m(-2) and 500 cd m(-2) at 20 mA cm(-2)) and efficient (maximum external quantum efficiency of 3.1% at 1 mA cm(-2)) red (CIE, x = 0.66, y = 0.34) organic light-emitting diodes (OLEDs) employ arylaminospirobifluorene-substituted fumaronitriles as the novel non-dopant red emitter.
Low surface energy coatings or anti-wetting agents play an essential role in microelectronics, anti-fogging and anti-fouling applications, and even have promising medical applications. Currently, perfluoroalkyl substituted polymethacrylates (PFPMs) are widely in use, and the anti-wetting properties of these and related polymers are believed to arise from the segregation of CF groups to the surf...
In the title compound, C(35)H(32)N(4)O(4), the pyrazole ring forms a dihedral angle of 15.04 (8)° with the adjacent pyrimidine ring. The pyrimidine ring forms dihedral angles of 9.95 (8) and 1.86 (7)° with its adjacent meth-oxy-substituted benzene rings, whereas the equivalent angles are 80.24 (9) and 11.55 (9)° for the pyrazole ring and its adjacent benzene rings. The crystal packing features ...
a number of n-arylmethyl substituted indole derivatives have been synthesized and their effectiveness against adp and arachidonic acid induced platelet aggregation in human plasma was determined. the desired compounds were synthesized by reacting the appropriate aniline derivative with isatin (or substituted isatin) to form the corresponding imine structures. the so formed compound was then act...
substituted 2, 4- diphenyl quinolines were synthesized by a multicomponent domino reaction of anilines, aldehydes and terminal aryl alkynes. the synthetic pathway involves the formation of an imine, followed by the intermolecular addition of an alkyne to the imine. this intermediate immediately undergoes ring closure and oxidative aromatization. the reaction is catalyzed by natural kaolin, a st...
The structural basis for the extraordinary stability of a triple-stranded oligonucleotide in which the third strand contains 2'-aminoethoxy-substituted riboses is investigated by NMR spectroscopy. The enhanced stability of the modified triplex in comparison to the unmodified DNA triplex of the same sequence can be attributed to strong interactions of the aminoethoxy groups of the third strand w...
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