1071841-77-4Relevant academic research and scientific papers
A novel N-terminal degradation reaction of peptides via N-amidination
Hamada, Yoshio
, p. 1690 - 1695 (2016/12/22)
The cleavage of amide bonds requires considerable energy. It is difficult to cleave the amide bonds in peptides at room temperature, whereas ester bonds are cleaved easily. If peptide bonds can be selectively cleaved at room temperature, it will become a powerful tool for life science research, peptide prodrug, and tissue-targeting drug delivery systems. To cleave a specific amide bond at room temperature, the decomposition reaction of arginine methyl ester was investigated. Arginine methyl ester forms a dimer; the dimer releases a heterocyclic compound and ornithine methyl ester at room temperature. We designed and synthesized N-amidinopeptides based on the decomposition reaction of arginine methyl ester. Alanyl-alanine anilide was used as the model peptide and could be converted into N-degraded peptide, alanine anilide, via an N-amidination reaction at close to room temperature. Although the cleavage rate in pH 7.4 phosphate buffered saline (PBS) at 37?°C was slow (t1/2?=?35.7?h), a rapid cleavage rate was observed in 2% NaOH aq (t1/2?=?1.5?min). To evaluate the versatility of this reaction, a series of peptides with Lys, Glu, Ser, Cys, Tyr, Val, and Pro residue at the N-terminal were synthesized; they showed rapid cleavage rates of t1/2values from 1?min to 10?min.
Proline-based dipeptides with two amide units as organocatalyst for the asymmetric aldol reaction of cyclohexanone with aldehydes
Chen, Fubin,Huang, Shi,Zhang, Hui,Liu, Fengying,Peng, Yungui
, p. 9585 - 9591 (2008/12/22)
A series of proline-based dipeptide organocatalysts with two amide units (1-16) have been developed and evaluated in the direct catalytic asymmetric aldol reactions of aldehydes with cyclohexanone. These catalysts showed good solubility in organic solvents compared with their corresponding carboxyl terminal dipeptides. The robust amide bond formation allowed structural modifications and fine tuning of catalyst properties by varying the stereo and electronic effects of the terminal amide to affect the ability of hydrogen bonding formation between the catalysts and the substrates. The reactions proceeded smoothly in high yields (up to 99%), enantioselectivities (up to 98% ee) and anti-diastereoselectivities (up to 99:1) in the presence of bifunctional organocatalyst 4 under the optimal reaction conditions.
