1357075-57-0Relevant academic research and scientific papers
Diastereoselective preparation of (R)- and (S)-2-methoxy-2-phenylpent-3- ynoic acids and their use as reliable chiral derivatizing agents
Perez-Estrada, Salvador,Joseph-Nathan, Pedro,Jimenez-Vazquez, Hugo A.,Medina-Lopez, Manuel E.,Ayala-Mata, Francisco,Zepeda, L. Gerardo
experimental part, p. 1640 - 1652 (2012/04/23)
Benzoyl-S,O-acetals 1a and 1b were used as chiral auxiliaries to achieve the diastereoselective preparation of both enantiomers of 2-methoxy-2- phenylpent-3-ynoic acids (MPPAs). The latter were condensed with several chiral secondary alcohols and some primary amines to evaluate their potential as chiral derivatizing agents (CDAs). The 1H NMR spectra of the corresponding esters and amides showed strong consistency with the absolute configuration of the carbinol and amine moieties, whose observed ΔδL1 and ΔδL2 values were in the ranges of 0.1-0.4 and 0.02-0.12 ppm, respectively.
Synthesis and conformational studies of peptido-squaramide foldable modules: A new class of turn-mimetic compounds
Martinez, Luis,Sampedro, Angel,Sanna, Elena,Costa, Antoni,Rotger, Carmen
supporting information; experimental part, p. 1914 - 1921 (2012/04/23)
The β-turn unit is one of the most important secondary structure elements in proteins. The access to new conformationally controlled foldable modules can afford compounds with interesting bioactivities. Here, we describe a new family of peptido-squaramide foldable modules based on the considerable potential of the squaramide unit as a hydrogen bond donor and acceptor as well as the low rotational barrier of the C-N bond. The conformational analysis by NMR of these modules in chloroform and acetonitrile solution shows that a disecondary squaramide with the 4-aminobutyric acid in one of its substituents can mimic the β-turn structure driven by the formation of an intramolecular hydrogen bonded ten-membered ring. This structure, although flexible, has been successfully combined with dipeptide chains to induce the formation of a hairpin-like structure driven by the formation of several cross-strand intramolecular hydrogen bonds.
