124818-94-6Relevant articles and documents
Synthesis of Enantiomerically Pure 3-Substituted Piperazine-2-acetic Acid Esters as Intermediates for Library Production
Reddy Guduru, Shiva Krishna,Chamakuri, Srinivas,Raji, Idris O.,MacKenzie, Kevin R.,Santini, Conrad,Young, Damian W.
, p. 11777 - 11793 (2018/09/27)
The piperazine heterocycle is broadly exploited in FDA-approved drugs and biologically active compounds, but its chemical diversity is usually limited to ring nitrogen substitutions, leaving the four carbon atoms underutilized. Using an efficient six-step synthesis, chiral amino acids were transformed into 3-substituted piperazine-2-acetic acid esters as diastereomeric mixtures whose cis and trans products (dr 0.56 a? 2.2:1, respectively) could be chromatographically separated. From five amino acids (both antipodes) was obtained a complete matrix of 20 monoprotected chiral 2,3-disubstituted piperazines, each as a single absolute stereoisomer, all but one in multigram quantities. In keeping with our overall purpose of constructing more Csp3-enriched compound libraries for drug discovery, these diverse and versatile piperazines can be functionalized on either nitrogen atom, allowing them to be used as scaffolds for parallel library synthesis and as intermediates for the production of novel piperazine compounds.
Efficient synthesis of functionalized olefins by Wittig reaction using Amberlite resin as a mild base
Valkute, Tushar R.,Aratikatla, Eswar K.,Bhattacharya, Asish K.
, p. 581 - 589 (2017/03/15)
A convenient procedure for the synthesis of olefins by the reaction of stabilized, semistabilized, and nonstabilized phosphorous ylides with various aldehydes or ketone using Amberlite resin as a mild base is described. Our developed method offers facile and racemization-free synthesis of α,β-unsaturated amino esters and chiral allylic amine. The developed methodology offers mild reaction conditions, high efficiency, and facile isolation of the final products, a practical alternative to known procedures.
Non-classical Helices with cis Carbon–Carbon Double Bonds in the Backbone: Structural Features of α,γ-Hybrid Peptide Foldamers
Ganesh Kumar, Mothukuri,Thombare, Varsha J.,Katariya, Mona M.,Veeresh, Kuruva,Raja, K. Muruga Poopathi,Gopi, Hosahudya N.
supporting information, p. 7847 - 7851 (2016/07/07)
The impact of geometrically constrained cis α,β-unsaturated γ-amino acids on the folding of α,γ-hybrid peptides was investigated. Structure analysis in single crystals and in solution revealed that the cis carbon–carbon double bonds can be accommodated into the 12-helix without deviation from the overall helical conformation. The helical structures are stabilized by 4→1 hydrogen bonding in a similar manner to the 12-helices of β-peptides and the 310helices of α-peptides. These results show that functional cis carbon–carbon double bonds can be accommodated into the backbone of helical peptides.
