174176-25-1Relevant academic research and scientific papers
Cyclizing pentapeptides: Mechanism and application of dehydrophenylalanine as a traceless turn-inducer
Le, Diane N.,Riedel, Jan,Kozlyuk, Natalia,Martin, Rachel W.,Dong, Vy M.
, p. 114 - 117 (2017/11/27)
Dehydrophenylalanine is used as a traceless turn-inducer in the total synthesis of dichotomin E. Macrocyclization of the monomer is achieved in high yields and selectivity over cyclodimerization under conditions 100 times more concentrated than previously achieved. The enamide facilitates ring closing, and Rh-catalyzed hydrogenation of the unsaturated cyclic peptide results in selective formation of the natural product or its epimer, depending on our choice of phosphine ligand. NMR analysis and molecular modeling revealed that the linear peptide adopts a left-handed α-turn that preorganizes the N- and C-termini toward macrocyclization.
Dehydrooligopeptides. XX. Unusual Peptide Bond Cleavage of Dehydrotripeptide Esters Containing α-Dehydroamino Acid Residue at P2 by Using Papain
Shin, Chung-Gi,Arai, Kazushige,Hotta, Keitaro,Kakusho, Takeshi
, p. 1427 - 1434 (2007/10/03)
Enzymatic ester hydrolysis and coupling of various N- protected Δ2 - dehydrotripeptide methyl esters (Boc-AA-ΔAA-AA-OMe) (4) by using protease papain in Mcllvaine buffer are mainly described. The substrates (4) used were prepared by one-pot coupling of N-carboxy-α-dehydroamino acid anhydride (ΔAA·NCA) with N- and C-component L-α-amino acids (AA). Even in the enzymatic reaction of 4 containing an unusual ΔAA residue, the normal ester hydrolysis took place to give Boc-AA-ΔAA-AA-OH (6) and, in certain cases, the interesting unusual peptide bond cleavage at P2 of 6 occured further to give the unexpected N-(1,2-dioxoalkyl)-AA-OH. Besides examining in detail the differences between the enzymatic actions to the structures of 4, we also studied the mechanisms of the ester and peptide bond hydrolyses. As the results, the reverse enzymatic coupling of 4 with H-AA-ΔVal-OMe was first achieved to give dehydropentapeptide containing two ΔAA residues.
