619-56-7Relevant articles and documents
Advantage of anaerobic conditions in the highly enantioselective synthesis of α,α-dialkyl-α-amino acids by chiral phase-transfer catalysis
Ooi,Takeuchi,Ohara,Maruoka
, p. 1185 - 1187 (2001)
Intervention of the enolate oxidation in the catalytic asymmetric phase-transfer alkylation of protected α-amino acid derivatives under aerobic conditions has been addressed, and anaerobic conditions have been introduced to obtain synthetically satisfactory chemical yields as well as a high level of enantioselectivity.
Design of gp120 HIV-1 entry inhibitors by scaffold hopping via isosteric replacements
Ahmed, Shahad,Altieri, Andrea,Belov, Dmitry S.,Curreli, Francesca,Debnath, Asim K.,Iusupov, Ildar R.,Kurkin, Alexander V.,Manasova, Ekaterina V.,Markov, Pavel O.,Spiridonov, Evgeniy A.
, (2021/07/13)
We present the development of alternative scaffolds and validation of their synthetic pathways as a tool for the exploration of new HIV gp120 inhibitors based on the recently discovered inhibitor of this class, NBD-14136. The new synthetic routes were based on isosteric replacements of the amine and acid precursors required for the synthesis of NBD-14136, guided by molecular modeling and chemical feasibility analysis. To ensure that these synthetic tools and new scaffolds had the potential for further exploration, we eventually tested few representative compounds from each newly designed scaffold against the gp120 inhibition assay and cell viability assays.
Process Development of the Copper(II)-Catalyzed Dehydration of a Chiral Aldoxime and Rational Selection of the Co-Substrate
Gr?ger, Harald,Nonnhoff, Jannis
, (2021/12/14)
The access towards chiral nitriles remains crucial in the synthesis of several pharmaceuticals. One approach is based on metal-catalyzed dehydration of chiral aldoximes, which are generated from chiral pool-derived aldehydes as substrates, and the use of a cheap and readily available nitrile as co-substrate and water acceptor. Dehydration of N-acyl α-amino aldoximes such as N-Boc-l-prolinal oxime catalyzed by copper(II) acetate provides access to the corresponding N-acyl α-amino nitriles, which are substructures of the pharmaceuticals Vildagliptin and Saxagliptin. In this work, a detailed investigation of the formation of the amide as a by-product at higher substrate loadings is performed. The amide formation depends on the electronic properties of the nitrile co-substrate. We could identify an acceptor nitrile which completely suppressed amide formation at high substrate loadings of 0.5 m even when being used with only 2 equivalents. In detail, utilization of trichloroacetonitrile as such an acceptor nitrile enabled the synthesis of N-Boc-cyanopyrrolidine in a high yield of 92 % and with full retention of the absolute configuration.
