Theoretical Study on the Cyclization Mechanism of Dipeptides

Xia, Peng; Wang, Chen; Qi, Chenze

doi:10.1002/cjoc.201300035

Cited by 6 publications

(3 citation statements)

References 60 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The resultant intermediate decomposes after the proton transfer to the leaving group. 26,75,106,107 This mechanism is illustrated in Fig. 9 for the oligoglycines of this work.…”

Section: Formation Of the Cyclic Dipeptide And Cyclization Mechanismsmentioning

confidence: 69%

Glycine homopeptides: the effect of the chain length on the crystal structure and solid state reactivity

2014

View full text Add to dashboard Cite

show abstract

“…The resultant intermediate decomposes after the proton transfer to the leaving group. 26,75,106,107 This mechanism is illustrated in Fig. 9 for the oligoglycines of this work.…”

Section: Formation Of the Cyclic Dipeptide And Cyclization Mechanismsmentioning

confidence: 69%

Glycine homopeptides: the effect of the chain length on the crystal structure and solid state reactivity

2014

View full text Add to dashboard Cite

show abstract

“…In the last step, the cyclic intermediate C releases water through a low-barrier proton shift from the NH 2 to OH group of the tetrahedral carbon. This transfer is assisted by the adjacent ethoxy group, whose absence would otherwise require formation of a highly strained four-membered ring or the entropically disfavored involvement of an extra solvent molecule, resulting in higher energy barriers . Next, the formed water molecule is released, ultimately resulting in separate products, which are characterized by Δ G = −14.2 kcal mol –1 relative to the separate reactants (see the SI for details).…”

Section: Resultsmentioning

confidence: 99%

En Route to a Heterogeneous Catalytic Direct Peptide Bond Formation by Zr-Based Metal–Organic Framework Catalysts

et al. 2021

View full text Add to dashboard Cite

Peptide bond formation is a challenging, environmentally and economically demanding transformation.Catalysis is key to circumvent current bottlenecks. To date, many homogeneous catalysts able to provide synthetically useful methods have been developed, while heterogeneous catalysts remain largely restricted to the studies addressing the prebiotic formation of peptides. Here, the catalytic activity of Zr6-based metalorganic frameworks (Zr-MOFs) towards the peptide bond formation is investigated using the dipeptide cyclization as a model reaction. Unlike previous catalysts, Zr-MOFs largely tolerate water, and reactions are carried out under ambient conditions. Notably, the catalyst is recyclable and no additives to activate COOH group are necessary, which are common limitations of previous methods. In addition, broad reaction scope tolerates substrates with bulky and Lewis basic groups. The reaction mechanism was assessed by intermolecular peptide bond formation. While intrinsic challenges associated with the catalyst structure and water removal limit a more general intermolecular reaction scope under current conditions, the results suggest that further design of Zr-MOF catalysts could render these materials broadly useful as heterogeneous catalysts for this challenging transformation.

show abstract

“…The proposed mechanism in solution involves neutral dipeptide . The first step is the isomerization of the amide, from trans to cis geometry of the peptide bond, as confirmed by theoretical studies . This allows nucleophilic addition of the amino group to the carbonyl carbon atom and then the loss of water to form the DKP ring.…”

Section: Resultsmentioning

confidence: 80%

Solid‐state synthesis of cyclo LD‐diphenylalanine: A chiral phase built from achiral subunits

2020

View full text Add to dashboard Cite

The solid-state structure of LL/DD or LD/DL diphenylalanine diluted in KBr pellets is studied by infrared (IR) absorption and vibrational circular dichroism (VCD) spectroscopy. The structure depends on the absolute configuration of the residues. The natural LL diphenylalanine exists as a mixture of neutral and zwitterionic structures, depending on the humidity of the sample, while mostly the zwitterion is observed for LD diphenylalanine whatever the experimental conditions. The system undergoes spontaneous cyclization upon heating at 125 C, resulting to the formation of a diketopiperazine (DKP) dipeptide as the only product. The reaction is faster for LD than for LL diphenylalanine. As expected, LL and DD diphenylalanine react to form the LL and DD enantiomers of cyclo diphenylalanine. Interestingly, the DKP dipeptides formed from the LD or DL diphenylalanine show unexpected optical activity, with opposite VCD spectra for the products formed from the LD and DL reagents. This is explained in terms of chirality synchronization between the monomers within the crystal, which retain the symmetry of the reagent, resulting to the formation of a new chiral phase made from transiently chiral molecules. K E Y W O R D Schirality synchronization, diketopiperazine (DKP), peptides, vibrational circular dichroism (VCD), vibrational spectroscopy

show abstract

Theoretical Study on the Cyclization Mechanism of Dipeptides

Cited by 6 publications

References 60 publications

Glycine homopeptides: the effect of the chain length on the crystal structure and solid state reactivity

Glycine homopeptides: the effect of the chain length on the crystal structure and solid state reactivity

En Route to a Heterogeneous Catalytic Direct Peptide Bond Formation by Zr-Based Metal–Organic Framework Catalysts

Solid‐state synthesis of cyclo LD‐diphenylalanine: A chiral phase built from achiral subunits

Contact Info

Product

Resources

About