141232-74-8Relevant articles and documents
Novel l-prolyl-l-leucylglycinamide (PLG) tripeptidomimetics based on a 2-azanorbornane scaffold as positive allosteric modulators of the D2R
Sampaio-Dias, Ivo E.,Sousa, Carlos A. D.,García-Mera, Xerardo,Ferreira Da Costa, Joana,Caama?o, Olga,Rodríguez-Borges, José E.
, p. 11065 - 11069 (2016/12/09)
An efficient and straightforward orthogonal methodology was successfully developed to achieve constrained l-prolyl-l-leucylglycinamide (PLG) analogues starting from two proline mimetics based on a 2-azanorbornane scaffold. A preliminary dopamine D2 receptor radiolabeled binding assay with [3H]-N-propylnorapomorphine shows that enantiopurity of PLG peptidomimetics based on 2-azanorbornane is a requirement to achieve statistically significant positive modulators of the D2 receptor. This is the first documented active peptidomimetic of PLG whose bioactivity is not correlated with the C-terminal carboxamide pharmacophore and which cannot adopt the hypothesized type II β-turn conformation.
Experimental and DFT study of the aza-Diels-Alder reaction between cyclopentadiene and protonated benzylimine derivated from glyoxylates
Rodríguez-Borges, José Enrique,García-Mera, Xerardo,Fernández, Franco,Lopes, V. Hugo C.,Magalh?es,Cordeiro, M. Natália D. S.
, p. 10951 - 10957 (2007/10/03)
The Diels-Alder reaction of protonated N-benzyl imine of methyl glyoxylate with cyclopentadiene in different solvents gave mixtures of exo/endo adducts. The exo/endo selectivity of the reaction was elucidated by NMR experiments. Theoretical calculations by means of density functional theory (DFT) at the B3LYP/6-31G(d) level have also been performed to elucidate the molecular mechanism of this reaction. The DFT results suggest a highly asynchronous concerted mechanism, which in turn can explain the preferred exo stereoselectivity of the reaction. Inclusion of solvent effects enhances the exo selectivity, and this effect increases with the polarity of the solvent, in good agreement with the experimental findings.
