40350-84-3Relevant articles and documents
Dual stereocontrol in aldol reactions catalysed by hydroxyproline derivatives in the presence of a large amount of water
Gurka, András A.,Sz?ri, Kornél,Bartók, Mihály,London, Gábor
supporting information, p. 936 - 942 (2016/09/13)
Parameters influencing dual stereocontrol in aldol reactions of water miscible acetone with aromatic aldehydes in the presence of a large amount of water using hydroxyproline based catalysts were studied. Stereocontrol was achieved by changing the acidity and basicity of the reaction media by the addition of achiral salts in the presence of a single chiral catalyst. Under acidic conditions (NH4Cl salt) the (R)-aldol product was formed in excess while basic aqueous media (carboxylate salts) led to the enrichment of the (S)-enantiomer. Reaction conditions under which the reaction is feasible were optimised and the effect of the structure of the hydroxyproline-based catalysts was investigated. The results show that the formation of a biphasic micellar system and the presence of an appropriate catalyst are both crucial for the reaction to occur. Although the catalyst structure influenced the formation and stabilisation of the micellar system to a large extent, its effect on the enantioselectivities were found to be less pronounced.
Capped dipeptide phenethylamide inhibitors of the HCV NS3 protease
Nizi, Emanuela,Koch, Uwe,Ontoria, Jesus M.,Marchetti, Antonella,Narjes, Frank,Malancona, Savina,Matassa, Victor G.,Gardelli, Cristina
, p. 2151 - 2154 (2007/10/03)
The N-terminal aminoacid of phenethylamide tripeptide inhibitors of the hepatitis C virus NS3 protease can be replaced with an α-hydroxy acid to obtain more 'drug like' inhibitors with low micromolar activity. The preferred S-configuration of the capping
