688-12-0Relevant articles and documents
Investigation of peptoid chiral stationary phases terminated with N′-substituted phenyl-L-proline/leucine amide
Wu, Haibo,Song, Guangjun,Liang, Xinmiao,Ke, Yanxiong
supporting information, p. 2791 - 2797 (2013/08/23)
Eight peptoid chiral stationary phases (CSPs) terminated with N′-substituted phenyl-L-proline or L-leucine amide were prepared and evaluated under normal phase mode. With 59 racemic analytes, we compared the enantiomeric separations on CSPs terminated with p-methylphenyl, p-chlorophenyl and unsubstituted phenyl. For short peptoid selectors containing only one S-N-(1-phenylethyl) glycine (Nspe) unit, the terminal p-methyl substituent did not affect chiral recognition abilities significantly. In L-proline amide terminated CSPs, p-chloro substituent resulted in obviously inferior selectivity while in L-leucine amide terminated CSPs, it worked much better. Longer peptoid selectors containing two more Nspe units generally performed much better than the shorter ones, due to the great contributions of peptoid chain to chiral recognition. Meanwhile, the effects of the terminal substituent on selectivity were found changed on these CSPs. For CSPs terminated with L-leucine amide, the terminal p-chloro substituent in longer selector no longer produced the best recognition ability; the CSP with unsubstituted phenyl instead performed best. Comparison of these peptoid CSPs varied in terminal substituents and chain length was conducted to gain a better understanding of the chiral recognition mechanism of this type CSP and promote the development of more useful CSPs. Copyright
Synthesis and transport studies of model dipeptides with modified N-terminal amino groups into E. coli K12 mutant strains
Nowak-Jary,Andruszkiewicz
experimental part, p. 1959 - 1966 (2010/07/04)
The synthesis of Interminable guanidine derivatives of three dipeptides Ala-Ala, Ala-Leu, Ala-Phe and three dipeptides containing betaine as an N-terminal amino acid: Bet-Ala, Bet-Leu, Bet-He has been carried out. The transport studies of the obtained pseudopeptides and corresponding natural peptides into E. coli Kl2 mutant strains have also been performed. The results indicate that modified dipeptides containing N-terminal guanidine or betaine are not transported into E. coli K12 cells.