18211-41-1Relevant academic research and scientific papers
General and practical carboxyl-group-directed remote C-H oxygenation reactions of arenes
Wang, Yang,Gulevich, Anton V.,Gevorgyan, Vladimir
, p. 15836 - 15840 (2014/04/03)
Two methods for remote aromatic C-H oxygenation reactions, have been developed. Method1, the Cu-catalyzed oxygenation reaction, is highly efficient for cyclization of electron-neutral and electron-rich biaryl carboxylic acids into 3,4-benzocoumarins. Method2, the K2S2O 8-mediated oxygenation reaction, is more general and practical for cyclization of substrates with electron-donating and -withdrawing groups (see scheme). Copyright
A practical preparation of 2-carboxyphenylboronic acid and its application for the preparation of biaryl-2-carboxylic acids using Suzuki coupling reactions
Tao, Bin,Goel, Subhash C.,Singh, Jagvir,Boykin, David W.
, p. 1043 - 1046 (2007/10/03)
A practical synthesis of 2-carboxyphenylboronic from 2-tolylboronic acid and aqueous potassium permanganate under mild conditions is reported. The title compound couples with aryl bromides containing electron-withdrawing groups to give biaryl-2-carboxylic
Quantum-chemical substantiation of the reactivity and regioselectivity of nitration of biphenyl derivatives
Kofanov,Sokolov,Kolobov,Ovchinnikov
, p. 1269 - 1271 (2007/10/03)
Quantum-chemical calculations were used to substantiate the reactivity and regioselectivity of nitration of benzene, biphenyl, and carboxy-substituted biphenyls.
The effect of carboxy group on nitration of carboxylic acids from biphenyl series
Kolobov,Ovchinnikov,Kofanov,Krasovskaya,Danilova,Kazina
, p. 1653 - 1655 (2007/10/03)
Nitration of benzene, 2-biphenylcarcoxylic acid, and 3,4-biphenyldicarboxylic acid in acetic acid medium was studied. Under identic conditions mononitration of benzene and 3,4-biphenyldicarboxylic acid occurred with similar rate and in zero order with respect to substrate. The nitration of 2-biphenylcarboxylic acid was faster than that of benzene and was first order with respect to the acid. The result obtained was rationalized as primary interaction of the carboxy group of the 2-biphenylcarboxylic acid with the nitracidium ion. The interaction between the nitrating species and the carboxy groups of the 3,4-biphenyldicarboxylic acid does not afford nitrated products.
Construction of a family of biphenyl combinatorial libraries: Structure- activity studies utilizing libraries of mixtures
Neustadt, Bernard R.,Smith, Elizabeth M.,Lindo, Neil,Nechuta, Terry,Bronnenkant, Alan,Wu, Arthur,Armstrong, Lydia,Kumar, Chandra
, p. 2395 - 2398 (2007/10/03)
A set of biphenyl aminoacid building blocks has been synthesized. These were used to construct partially-peptidic combinatorial libraries as equimolar multi-component samples. Activity of members of this library as vitronectin receptor antagonists is described, together with SAR studies of the most active members. These studies illustrate several important features of combinatorial libraries.
Design and synthesis of non-peptide Ras CAAX mimetics as potent farnesyltransferase inhibitors
Qian, Yimin,Vogt, Andreas,Sebti, Sa?d M.,Hamilton, Andrew D.
, p. 217 - 223 (2007/10/03)
Cysteine farnesylation of the ras oncogene product Ras is required for its transforming activity and is catalyzed by farnesyltransferase (FTase). The Ras carboxyl terminal tetrapeptide CAAX (C is cysteine, A is any aliphatic amino acid, X is methionine or serine) is the minimum sequence for FTase recognition. We report here the design, synthesis, and biological characterization of Ras CAAX non-peptide mimetics in which the cysteine is linked through a reduced pseudopeptide bond to 4-amino-3'-carboxybiphenyl. These non-peptide mimetics are potent inhibitors of FTase (IC50 = 40 nM for the most potent inhibitor) and are highly selective for FTase over GGTase I (geranylgeranyltransferase I). They are not substrates for farnesylation, do not have peptidic features, and have no hydrolyzable bonds. Structure- activity studies reveal the importance of the position of the carboxylic acid on the aryl ring as well as the reduction of the cysteine amide bond. Substitution at the 2-position of 4-amino-3'-carboxybiphenyl increases inhibitory potency, while the removal of the carboxylic acid results in a 10- fold loss of inhibitory activity.
The Fragment Ion C13H9O2 m/z 197 in the Mass Spectra of 2-(2'-R-phenyl)benzoic Acids
Gillis, Richard G.,Porter, Quentin N.
, p. 203 - 207 (2007/10/02)
In the electron impact mass spectrum of 2-(2'-R-phenyl)benzoic acids where R = H, NO2, OCH3, COOH, or Br, an abundant fragment ion m/z 197 is formed by an ipso substitution in which R is expelled as a radical.The structure of the ion m/z 197 has been shown by collision-activated dissociation to be identical with that of the protonated molecule formed by methane chemical ionization of 6H-dibenzopyran-6-one.
Intramolecular Cyclisations of Biphenyl-2-carboxyl Radicals: Evidence for a Π-State Aroyloxyl Radical
Glover, Stephen A.,Golding, Stephen L.,Goosen, Andre,McCleland, Cedric W.
, p. 842 - 848 (2007/10/02)
Biphenyl-2-carboxyl radicals generated by homolysis of acyl hypoiodites cyclise intramoleculary giving mainly δ-lactones through Ar2-6 cyclisation. 2'-Alkoxybiphenyl-2-carboxyl radicals do not give the expected Ar1-5 cyclisation product but undergo a homolytic ipso-substitution of the 2'-substituent.The phenanthrene-4-carboxyl radical gives 5H-phenanthropyran-5-one.Consideration of the molecular orbitals involved suggests that the biphenyl-2-carboxyl radicals are in the ?-ground state and have a higher energy, and, therefore, a less thermally accessible Σ-state than the corresponding amido-radicals.It is suggested that acyloxyl radicals which readily decarboxylate have either a Σ-ground state or a thermally accessible excited Σ-state.
