26787-76-8Relevant academic research and scientific papers
TOPP: A novel nitroxide-labeled amino acid for EPR distance measurements
Stoller, Sven,Sicoli, Giuseppe,Baranova, Tatiana Y.,Bennati, Marina,Diederichsen, Ulf
supporting information; experimental part, p. 9743 - 9746 (2011/11/29)
A new tool: The amino acid 4-(3,3,5,5-tetramethyl-2,6-dioxo-4- oxylpiperazin-1-yl)-L-phenylglycine (TOPP), which has a rigid nitroxide spin label, can be used for EPR-based distance measurements in peptides. The key feature of the design is the defined orientation of the nitroxide in space with respect to the peptide backbone. EPR measurements provide evidence for the low conformational flexibility of the TOPP label. Copyright
Relaxing substrate specificity in antibody-catalyzed reactions: Enantioselective hydrolysis of N-Cbz-amino acid esters
Tanaka, Fujie,Kinoshita, Keiko,Tanimura, Ryuji,Fujii, Ikuo
, p. 2332 - 2339 (2007/10/03)
For a catalytic antibody to be generally useful for organic synthetic chemistry, it must be able to accept a broad range of substrates, yet retain high selectivity. In this work, we propose a hapten design to endow antibody catalysts with two opposing qualities, such as high enantioselectivity and broad substrate specificity. Racemic hapten 2 induced two separate classes of catalytic antibodies to hydrolyze either the L- or D-isomers of N-Cbz-amino acid esters 1. In the kinetic resolution of racemic ester 9, antibodies 7G12 and 3G2 gave 96% ee of L-10 and 94% ee of D-10, respectively. In addition, antibody 7G12 displayed broad substrate specificity, hydrolyzing the L-esters of Ala (1a), Leu (1b), Norleu (1c), Met (1d), Phe (1e), Val (1f), and phenylglycine (1g) with high enantioselectivity. Antibody 3G2 also hydrolyzed the D-isomers of these esters without sacrificing the enantioselectivity. This observation suggests that the use of haptens that fit snugly into the antigen-combining site, and leave the linker moiety outside, is an effective approach for the generation of catalytic antibodies with high selectivity and broad substrate applicability.
An Approach to a Synthetic Carboxylate-binding Pocket Based on β-Avoparcin
Stone, Martin J.,Dyk, Martha S. van,Booth, Paul M.,Williams, Dudley H.
, p. 1629 - 1635 (2007/10/02)
An approach to a macrocyclic lactam designed to bind to a carboxylate anion is described.The diaryl ether 8 was synthesised by Ullmann coupling of the protected 3-hydroxyphenylglycine derivative 7 and (E)-4-bromocinnamic acid methyl ester.Elaboration of an optically pure (R)-tyrosine synthon was achieved by transfer of electrophilic azide to the N-acyl oxazolidinone 12.The synthesis of a model system is also described.
