35593-55-6Relevant articles and documents
Probing α-Amino Aldehydes as Weakly Acidic Pronucleophiles: Direct Access to Quaternary α-Amino Aldehydes by an Enantioselective Michael Addition Catalyzed by Br?nsted Bases
García-Urricelqui, Ane,de Cózar, Abel,Mielgo, Antonia,Palomo, Claudio
supporting information, p. 2483 - 2492 (2020/12/25)
The high tendency of α-amino aldehydes to undergo 1,2-additions and their relatively low stability under basic conditions have largely prevented their use as pronucleophiles in the realm of asymmetric catalysis, particularly for the production of quaternary α-amino aldehydes. Herein, it is demonstrated that the chemistry of α-amino aldehydes may be expanded beyond these limits by documenting the first direct α-alkylation of α-branched α-amino aldehydes with nitroolefins. The reaction produces densely functionalized products bearing up to two, quaternary and tertiary, vicinal stereocenters with high diastereo- and enantioselectivity. DFT modeling leads to the proposal that intramolecular hydrogen bonding between the NH group and the carbonyl oxygen atom in the starting α-amino aldehyde is key for reaction stereocontrol.
Chemo- and Enantioselective Hydrogenation of α-Formyl Enamides: An Efficient Access to Chiral α-Amido Aldehydes
Zhang, Jian,Jia, Jia,Zeng, Xincheng,Wang, Yuanhao,Zhang, Zhenfeng,Gridnev, Ilya D.,Zhang, Wanbin
, p. 11505 - 11512 (2019/07/17)
In order to effectively synthesize chiral α-amino aldehydes, which have a wide range of potential applications in organic synthesis and medicinal chemistry, a highly chemo- and enantioselective hydrogenation of α-formyl enamides has been developed, catalyzed by a rhodium complex of a P-stereogenic bisphosphine ligand. Under different hydrogen pressures, the chiral α-amido aldehydes and β-amido alcohols were obtained in high yields (97–99 %) and with excellent chemo- and enantioselectivities (up to >99.9 % ee). The hydrogenation can be carried out on a gram scale and with a high substrate/catalyst ratio (up to 20 000 S/C), and the hydrogenated products were further converted into several important chiral products. Computations of the catalytic cycle gave a clear description for the R/S pathways, provided a reasonable explanation for the enantioselectivity, and revealed several other specific features.
Analogs design, synthesis and biological evaluation of peptidomimetics with potential anti-HCV activity
Lasheen, Deena S.,Ismail, Mohamed A.H.,Abou El Ella, Dalal A.,Ismail, Nasser S.M.,Eid, Sameh,Vleck, Susan,Glenn, Jeffrey S.,Watts, Andrew G.,Abouzid, Khaled A.M.
, p. 2742 - 2755 (2013/06/27)
Two series of peptidomimetics were designed, prepared and evaluated for their anti-HCV activity. One series possesses a C-terminal carboxylate functionality. In the other series, the electrophilic vinyl sulfonate moiety was introduced as a novel class of HCV NS3/4A protease inhibitors. In vitro based studies were then performed to evaluate the efficacies of the inhibitors using Human hepatoma cells, with the vinyl sulfonate ester (10) in particular, found to have highly potent anti-HCV activity with an EC50 = 0.296 μM. Finally, molecular modeling studies were performed through docking of the synthesized compounds in the HCV NS3/4A protease active site to assess their binding modes with the enzyme and gain further insight into their structure-activity relationships.
