2-Aminophenyl boronates

The synthesis of dibenzoazepinones 29 from 2-(2-bromophenyl)acetic acid esters 27 and 2-aminophenyl boronates 28 was reported, involving one-pot Suzuki-Miyaura coupling and subsequent lactamization reactions (13TL2916). 

Sharma s group developed the synthesis of dibenzoazepinones from 2-(2-bromophenyl)acetic acid esters and 2-aminophenyl boronate. In the presence of Pd(PPh3)4 and CS2CO3 in dimethozq ethane at 125-130 °C, the desired products were formed in moderate yields (Scheme 4.19). 

Diethylboryl)pyridines and (3-Aminophenyl)boronic Acid Derivatives... 

A structurally related tetrameric macroheterocycle is compound 13 that is prepared in a one-pot synthesis (yield 64%) from salicylaldehyde and (3-aminophenyl)boronic acid in methanol (Fig. 4). Due to its insolubility it has been characterized only by mass spectrometry. If a substitutent is introduced at the imine function (R = Me, Ph), trimeric structures (14 and 15) are... 

Fig. 4. Tetrameric 13 and trimeric 14, 15 macrocyclic structures obtained from (3-aminophenyl)boronic acid derivatives...

Typically, the boronic acid group is part of an aminophenyl boronic acid derivative, and this group has been used for bioconjugation and affinity chromatography purposes (Burnett et al., 1980 O Shannessy and Quarles, 1987). A common partner for a phenyl boronic acid group in bioconjugation is the salicylhydroxamic acid (SHA) group (Chapter 17, Section 3) (Reaction 59). 

Specific applications have been described for the separation of immunoglobulins.174 The ligand used and immobilized on a solid phase carriers was m- or p-aminophenyl boronic acid. Antibodies were adsorbed from feed... 

The Suzuki cross-coupling reaction between 1,2,5-trisubstituted pyrrole halides 1443 and 2-A -(/-butoxycarbonyl)-aminophenyl boronic acid 1444 performed with benzyl[bis(triphenylphosphine)]palladium(ll) chloride (PdBnCl(PPh3)2)... 

Aminophenyl boronic acid HAuCU Direct oxidation-reduction Cl , H2O PVA as disperser 15.5-39.4 nm (depending on PVA concentration) 29... 

Chemical sensors based on the competitive binding of sugars to the boronic add ligand have been reported. When 3-aminophenyl boronic acid was covalently linked to GSH-capped CdSe-ZnS QDs, the boronic acid ligand formed boronate esters with... 

J. H. Lee, Y. Kim, M. Y. Ha, E. K. Lee, and J. Choo, Immobilization of aminophenyl-boronic acid on magnetic beads for the direct determination of glycoproteins by matrix-assisted laser desorption ionization mass spectrometiy, J. Am. Soc. Mass Spec-trom. 16, 1456-1460 (2005). 

Fabre et al. electrochemically polymerized PABA using a fluoride catalyzed reaction [31]. The electropolymerization of 3-aminophenyl-boronic acid in 0.5 M H2SO4 aqueous solution was found to be inefficient (Figure 3.3, A). However, addition of fluoride strongly enhanced the polymerization rate (Figure 3.3, B). This effect was not observed with Cl or with unsubstituted polyaniline in the presence of fluoride. 

The ADP-ribose protein conjugates were purified on aminophenyl boronate columns as described by Adamietz et al. [23]. 

The Endogenous Mono- and Poly(ADPR) Nonhistone Proteins of Yoshida Hepatoma Cells can be Isolated by Aminophenyl Boronic Acid Chromatography... 

In order to assess the nuclear nonhistone proteins being ADP-ribosylated in association with DNA repair we have isolated the endogenous conjugates formed in DMS-treated cells by applying aminophenyl boronic acid chromatography to 0.2 M sulfuric acid precipitates of isolated nuclei [1]. With hepatoma cells, this procedure provided rou y 80% of the newly-formed conjugates in a highly purified form. The isolated fraction of histone-depleted (ADP-ribosyl) proteins comprised about 1% of total nuclear... 

This electron transfer was positively affected by the immobilization of glucose oxidase on glassy carbon modified by aminophenyl boronic acid [193] or adsorption on to metalized carbons [194]. Nevertheless, it was possible to achieve good electron transfer only by modification ( functionalization ) of the enzyme with redox compounds (ferrocene derivatives). The direct electrical communication between the modified enzyme and an electrode has been proved by cyclic voltammetry. Thus attention was paid to the construction of various types of modified glucose oxidase electrodes. For instance, Benneto et al. [195] describe an... 

Aminophenyl Boronate 4% cross-linked agarose Aminophenyl boronate n.a. 

Reprinted from Biosensors <6 Bioelectronics, 26, Ho, J. A. et ai, Ultrasensitive electrochemical detection of biotin using electrically addressable site-oriented antibody immobilization approach via aminophenyl boronic acid, 1021-7, Cop5right (2010), with permission from Elsevier.)... 

Freund has prepared polyaniline boronic acids by the electrochemical polymerization of 3-aminophenyl boronic acid [169, 170], The electrochemical potential of the polymer is sensitive to changes in the pK of the polymer as a result of boronic acid-diol complex formation. Fabre has also used polyaniline boronic acids as a con-ductiomeric sensor for dopamine [171]. 

This synthesis is based upon the Rh-catalyzed conjugate addition of aminophenyl boronates to the enone followed by cyclization to the 3,4-dihydroquinoline 112 and its... 

Other early work in this field included the use of tetrakis(p-aminophenyl)-porphyrin (Fig. 7a), which was electrodeposited onto glassy carbon and showed a near-Nernstian response to iodide [76]. Electrodeposited methylthiophene-methylpyrrole copolymer was deposited and shown to give a near-Nernstian response to bromide [77]. Pyrrole-3-boronate (Fig. 7b) could be deposited to give films with a good response and marked selectivity to fluoride [78]. A cobalt aminophthalocyanine could also be electropolymerised to give a good sensor for nitrite [79] or sulphide ion [80]. 

Fig.7 Structures of a tetrakis(p-aminophenyl)porphyrin, b pyrrole-3-boronic acid and c 1-methyl-3 (1-pyrrole-l-ylmethyl)pyridinium tetrafluorob orate...

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