Convenient Peptide Synthesis Using Unprotected α-Amino Acids Containing Another Hydrophilic Moiety under Basic Conditions

Abstract

Carboxylic acids 1 and 7 reacted effectively with unprotected α-amino acids 2 containing another hydrophilic moiety under basic conditions via activation by ethyl chloroformate and triethylamine to afford the corresponding amides in 74–99% yields.

Novel Triazole‐Containing “Dipeptides”: Synthesis, Molecular Docking and Analgesic Activity Studies

“…As a result of the optimization of possible parameters, the optimal temperature regime of the process and the ratio of reagents were established, which provide the best results for the target products. [14] A wide spectrum of action of triazole derivatives, on the one hand, and neuropathic pain as one of the unresolved and urgent problems of modern medicine, on the other hand, became a prerequisite for further study of antinociceptive activity. [1a,b] The choice of nAChR receptors as a potential target for the obtained compounds was due to their structure, the analysis of which revealed the presence of possible pharmacophore groups for binding to the selected receptor.…”

“…Based on these considerations, T. Ezawa and others have developed an effective method for producing dipeptides excluding the formation of byproducts and racemization of the target products. As a result of the optimization of possible parameters, the optimal temperature regime of the process and the ratio of reagents were established, which provide the best results for the target products [14] …”

Peptide‐Chain Elongation Using Unprotected Amino Acids in a Micro‐Flow Reactor

“…Moreover, generated CO 2 and alcohol can be removed easily. Imai et al . reported an in situ preparation of mixed carbonic anhydride using ClCO 2 Et, Et 3 N, in THF, and aqueous NaHCO 3 and its use in amidation with free amino acids.…”

“…To reduce the numbero fs ynthetic steps, waste, and cost, peptidec hain elongationsu sing unprotecteda mino acids have been investigated. The most frequently investigated approach involves the coupling of unprotected amino acid B in water with activated acyl species A (X = O-succinimide, [2] pentafluorophenol, [3] Op-C 6 H 4 NO 2 , [4] OCOR, [5] benzotriazole, [6] N 3 , [7] F [8] or others [9] )i na no rganic solvent, as showni nS cheme 1(I). How-ever,s low amidation in ab iphasic solvents ystems tends to lead to undesired racemization and/or hydrolysis of A.T his is one of the most challenging issues for achieving peptidec hain elongation using unprotecteda mino acids.…”