26348-68-5Relevant articles and documents
Silver comes into play: Henry reaction and domino cycloisomerisation sequence catalysed by [Ag(i)(Pc-L)] complexes
Tseberlidis, Giorgio,Dell'Acqua, Monica,Valcarenghi, Daniele,Gallo, Emma,Rossi, Elisabetta,Abbiati, Giorgio,Caselli, Alessandro
, p. 97404 - 97419 (2016/10/25)
We report herein the synthesis of new pyridine-containing macrocyclic ligands (Pc-L) bearing a non-innocent pendant arm, by exploiting both chiral and functional properties of natural amino acids. The obtained macrocyclic ligands were employed to synthesize well-defined cationic silver(i) complexes that were shown to be competent catalysts for the Henry (nitroaldol) reaction. Good to excellent yields and full selectivity in the β-nitroalcohol product were obtained starting from electron-poor aromatic aldehydes or other activated aldehydes such as furfural under mild reaction conditions. The straightforward synthesis of the macrocyclic ligands starting from cheap commercially available starting materials allowed the introduction of a suitable basic functionality into the ligand pendant arm, thus providing a bifunctional catalyst. Based on our previous experience in the [Ag(i)(Pc-L)] catalysed domino addition/cycloisomerisation reaction of o-alkynylbenzaldehydes and nucleophiles, the synthesis of isochromenes coupling the Henry reaction and the cycloisomerisation in a single step was subsequently explored. Although with low selectivity, [Ag(i)(Pc-L)] cationic complexes were able to promote such a cascade reaction and a possible mechanism based on experimental evidence has been proposed.
Nε-Modified lysine containing inhibitors for SIRT1 and SIRT2
Huhtiniemi, Tero,Suuronen, Tiina,Lahtela-Kakkonen, Maija,Bruijn, Tanja,J??skel?inen, Sanna,Poso, Antti,Salminen, Antero,Lepp?nen, Jukka,Jarho, Elina
supporting information; experimental part, p. 5616 - 5625 (2010/09/14)
Sirtuins catalyze the NAD+ dependent deacetylation of N ε-acetyl lysine residues to nicotinamide, O′-acetyl-ADP- ribose (OAADPR) and Nε-deacetylated lysine. Here, an easy-to-synthesize Ac-Ala-Lys-Ala sequence has been used as a probe for the screening of novel Nε-modified lysine containing inhibitors against SIRT1 and SIRT2. Nε-Selenoacetyl and N ε-isothiovaleryl were the most potent moieties found in this study, comparable to the widely studied Nε-thioacetyl group. The Nε-3,3-dimethylacryl and Nε-isovaleryl moieties gave significant inhibition in comparison to the Nε-acetyl group present in the substrates. In addition, the studied Nε- alkanoyl, Nε-α,β-unsaturated carbonyl and N ε-aroyl moieties showed that the acetyl binding pocket can accept rather large groups, but is sensitive to even small changes in electronic and steric properties of the Nε-modification. These results are applicable for further screening of Nε-acetyl analogues.
Time-dependence and preliminary SAR studies in inhibition of nitric oxide synthase isoforms by homologues of thiocitrulline
Goodyer, Claire L. M.,Chinje, Edwin C.,Jaffar, Mohammed,Stratford, Ian J.,Threadgill, Michael D.
, p. 3679 - 3680 (2007/10/03)
Treatment of Nα-Cbz-Nε -(2-hydroxyethylaminothiocarbonyl)-L-lysine N-(2-hydroxyethyl)amide with boiling hydrochloric acid gave Nε -(4,5-dihydrothiazol-2-yl)-L-lysine. This was a weak and non-isoform selective inhibitor of NOS, whereas Nε -aminothiocarbonyl-L-lysine and its methyl ester were potent, with IC 50=13 and 18 μM, respectively, against human iNOS and IC 50=3 and 8 μM, respectively, against rat nNOS. Time dependence was observed for inhibition of nNOS by the ester.
