2483-49-0Relevant articles and documents
The urea-dipeptides show stronger H-bonding propensity to nucleate β-sheetlike assembly than natural sequence
Ke, Damei,Zhan, Chuanlang,Li, Xiao,Li, Alexander D.Q.,Yao, Jiannian
experimental part, p. 8269 - 8276 (2009/12/26)
In this article, we report the distinct solution behavior of a set of urea-dipeptides to that of natural sequence. The urea-dipeptides adopt β-folding conformations and form into β-sheetlike assembly in chloroform. Most surprisedly, the urea-dipeptides tend to form interpeptide H-bonding interactions even at a concentration of as low as 0.1 mM, while the natural sequence shows H-bonding propensity at a concentration of about 7 mM, indicating that the urea-dipeptides show much stronger H-bonding propensity to nucleate formation of β-sheetlike assembly than the natural sequence. CD spectra reveal that the investigated urea-dipeptides have two negative CD bands, respectively, around 217 nm and 224 nm, supporting the β-folding conformations and in turn formation of β-sheetlike assembly. The β-sheetlike assembly is also confirmed by the XRD reflections, which give two typical d-spacings of 12.7 and 4.8 A?, respectively, corresponding to stacking periodicity of the β-sheets and the spacing between peptide backbones running orthogonal to the β-sheet axis.
A simple synthesis of imide-dipeptides
Ke, Damei,Zhan, Chuanlang,Li, Xiao,Li, Alexander D. Q.,Yao, Jiannian
experimental part, p. 1506 - 1510 (2009/12/24)
We report a simple approach to synthesize a new class of imide-dipeptides. This approach is mild, and the starting materials are the easily accessible amino acid derivatives. The imide-dipeptides were synthesized from the coupling of an amide and a 4-nitrophenyl activating ester of an amino acid. The acidic proton of the first amide was removed by 1 equivalent of n-butyl lithium to afford the corresponding amide anion which then reacted with the activating ester to give the desired imide derivatives. Georg Thieme Verlag Stuttgart.
Enzymatic peptide synthesis with p-guanidinophenyl and p- (guanidinomethyl)phenyl esters as acyl donors
Sekizaki, Haruo,Itoh, Kunihiko,Toyota, Eiko,Tanizawa, Kazutaka
, p. 846 - 849 (2007/10/03)
Two series of 'inverse substrates', N-Boc-amino acid p-guanidinophenyl and p-(guanidinomethyl)phenyl esters, were prepared as acyl donor components for enzymatic peptide synthesis. The kinetic behavior of these esters toward bovine and Streptomyces griseus (SG) trypsin was analyzed. The spatial requirement of the active site of these enzymes for catalytic efficiency is discussed based on the steric characteristics of the substrates. These substrates were found to couple readily with amino acid p-nitroanilides to produce peptides. SG trypsin was the most efficient catalyst among the enzymes tested (bovine, porcine, and SG trypsin).
A New Method for the Preparation of Active Esters Using Di-2-pyridyl Carbonate
Kim, Sunggak,Ko, Young Kwan
, p. 473 (2007/10/02)
The use of di-2-pyridyl carbonate in the presence of a catalytic amount of 4-dimethylaminopyridine is found to be very effective in the preparation of various active esters.
ACTIVATION OF A CARBOXY GROUP BY DIALKYL PYROCARBONATES. SYNTHESIS OF SYMMETRICAL ANHYDRIDES AND ARYL ESTERS OF N-PROTECTED AMINO ACIDS USING DI-tert-BUTYL PYROCARBONATE AS CONDENSING REAGENT
Pozdnev, V. F.,Chernaya, M. Yu.
, p. 333 - 337 (2007/10/02)
It has been shown that di-tert-butyl pyrocarbonate can be used as a condensing reagent in the production of anhydrides and some aryl esters of carboxylic acids.The synthesis of anhydrides and of phenyl, p-nitrophenyl, β-naphtyl, and quinolin-8-yl esters of N-protected amino acids is described.
