Bromoacetyl group

Figure 16.7 The ECAT mass tag consists of a DOTA metal chelate group that can coordinate a lanthanide metal ion and a bromoacetyl group for coupling to cysteine-containing proteins.

Figure 28.17 FeBABE is a bifunctional chelating agent containing an EDTA group on one side and a thiol-reactive bromoacetyl group on the other end. The EDTA group is coordinated with an iron ion.

A frequently used strategy to couple peptides to the surface of liposomes consists in the use hydrophobic/amphipathic anchors that are functionalized with maleimide or bromoacetyl groups, i.e., thiol-reactive functions, which give by reaction with HS-peptides very stable thioether linkages. These functions are conveniently introduced into hydrophobic anchors such as phospholipids, e.g., PE (9,10), the adjuvant PamsCAG (11) or cholesterol... 

Haloacetyl Method The haloacetyl method uses supports that contain lodoacetyl or bromoacetyl groups for the immobilization of ligands through sulfhydryl residues. These supports are usually prepared via the reaction of an amine-containing material with iodoacetic or bromoacetic acid in the presence of ethyldimethylaminopropyl carbodii-mide (EDC) at pH 4 to 5. EDC reacts with the carboxylic acid in iodo- or bromoacetic acid... 

It was found78 that quinuclidine ring closure takes place only if both the 4-bromoacetyl group and the nitrogen lone-pair electrons are in the axial position. Formation of this conformation in a transition state is facilitated by the introduction of bulky substituents at position 4 and at the piperidine nitrogen. Attempts to cyclize compounds without such bulky substituents (e.g., 4-bromoacetyl-piperidine) fail.78... 

C-terminal Max-segment by attaching a levolinic acid group at a lysine side chain (6—>9), and segments 7 and 9 were equipped with N-terminal bromoacetyl groups required for the thio-ester ligation. 

The acetyl group of 10-ace tyl-9-fluoro-3-methyl-7-oxo-2,3-dihydro-7//-pyrido[l,2,3-de]-l,4-benzoxazine-6-carboxylic acid was brominated with KBr03 and 48% HBr acid in AcOH, and the 2-bromoacetyl group was then converted into a 10-[2-aminomethyl-4-thiazolyl] group with phenylmethyl (2-amino-2-thioxoethyl)carbamate and subsequent treatment with 32% HBr (87JHC1509). 

Bromoacetyl groups cannot be used for thioether bond formation with cysteine residue in the presence of free amino groups. Only the chloroacetyl group is suitable for this purpose. 

Spectra/Ge 1 MAS B Spectrum Not known Bromoacetyl groups 10 C Not known Primary amino groups... 

A conceptually similar approach was used by Muhlbach and Schulz [96] to prepare a styrene and l-azabicyclo[4.2.0]octane block copolymer. By end-capping living PSt with ethylene oxide, and subsequent reaction with bromoacetyl bromide, a polymer with bromoacetyl groups was obtained which, together with AgCl04, acted as a macroinitiator for a living polymerization of the cyclic monomer (Scheme 11.26). Very little homopolymer was formed, however. Two distinct glass transition temperatures, at 10 and 94 °C, were observed with the block copolymer that corresponded to the poly(l-azabicyclo[4.2.0]octane) and PSt sequences, respectively, and indicated that the blocks were incompatible and phase-separated. 

Ease of preparation. Bromoacetyl groups can be attached to amino groups (unstable compounds can also be prepared with compounds containing hydroxyl, sulfhydryl, and imidazole) by convenient procedmres using bromoacetyl bromide, bromoacetic anhydride, or bromoacetyl-A -hydroxysuccinimide ester synthesis with bromoacetyl-A-hydroxy-... 

The bromoacetyl group was attached to the terminal amino group of the hapten at systematically increasing distances from the major haptenic moiety, thereby permitting labeling residues at various distances in the combining site. 

We have synthesized an aflSnity label which appears to mimic the effects of colchicine. It binds covalently to tubulin by specifically alkylating its a and subunits. The active function is the bromoacetyl group the modified ligand has one bromine which replaces one of the hydrogens of the acetyl group of colchicine. 

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