Esters in peptide synthesis

The / -(methylmercapto)phenyl ester has been prepared from an /-protected amino acid and 4-tH3SC6H40H (DCC, CH2CI2, 0°, 1 h 20°, 12 h, 60-70% yield). The p-(methylmercapto)phenyl ester serves as an unactivated ester that is activated on oxidation to the sulfone (H2O2, AcOH, 20°, 12 h, 60-80% yield) which then serves as an activated ester in peptide synthesis. ... 

This active ester was used for carboxyl protection of Fmoc-serine and Fmoc-threonine during glycosylation. The esters are then used as active esters in peptide synthesis. 

GHL Nefkens, GI Tesser. A novel activated ester in peptide synthesis (phthalimido esters). J Am Chem Soc 26, 1263, 1961. 

M Bodanszky. Active esters in peptide synthesis, in E Gross, J Meienhofer, eds. The Peptides Analysis, Synthesis, Biology, Academic, New York, 1979, pp 105-196. 

L Kisfaludy, M Low, O Nyeki, T Szirtes, I Schon. Utilization of pentafluorophenyl esters in peptide synthesis (DCC-XPhOH 1 3 complex). Liebigs Ann Chem 1421, 1973. 

Peptide synthesis. Vinyl esters of amino acids, prepared by transesterification with vinyl acetate, have been used as activated esters in peptide synthesis. The coupling reaction is best carried out in ethyl cyanoacetate, for this solvent suppresses the formation of colored products derived from liberated acetaldehyde. Racemization appears to be slight. 

Peptide synthesis. Stewart2 recommends use of pentamethylbenzyl esters in peptide synthesis because the protective group is cleaved rapidly by trifluoroacetic acid (also by HBr-AcOH). 2,4,6-Trimethylbenzyl esters are somewhat less labile. 

Bifunctional catalysis. Some time ago Swain and Brown1 observed that 2-hydroxypyridine catalyzed the mutarotation of tetramethylglucose by a concerted base-acid catalysis and that it is more effective than pyridine plus phenol. A few years later Beyerman and van den Brink2 showed that 2-hydroxypyridine and other bifunctional compounds catalyze the reaction of amines with cyano-methyl esters (reactive esters) as well as low-energy esters in peptide synthesis. Pyrazole and 1,2,4-triazole (1,1188), were equally effective. 

Bodanszky, M. (1979) Active Esters in Peptide Synthesis. in Peptides, E. Gross and J. Mcicn-hofer, Eds., Vol. 1, Academic Press. New York,... 

In 1955, almost simultaneously with the first publication on nitrophenyl esters, Farrington, Kenner and Turner proposed [23] the use of p-nitro-thiophenyl esters in peptide synthesis but in spite of the high reactivity of these intermediates their recommendation found few followers. 

M. Bodanszky, Active esters in peptide synthesis in The Peptides, Vol. I. (E. Gross, J. Meinhofer, eds.) Academic Press, New York 1979, pp. 105-196... 

Bodanszky, M. Active Esters in Peptide Synthesis, in The Peptides, vol. 1, Gross, E., Meienhofer, J. eds., pp. 105-196, New York, Academic Press 1979 Meienhofer, J. The Azide Method in Peptide Synthesis, in The Peptides, vol. 1, Gross, E., Meienhofer, J. eds., pp. 197-239, New York Academic Press 1979 Meienhofer, J. The Mixed Anhydride Method of Peptide Synthesis, in The Peptides vol. 1, Gross, E., Meienhofer, J. eds., pp. 263-314, New York, Academic Press 1979... 

Without additional reagents Acoxystannanes from distannoxanes Protection of carhoxyl groups as stannyl esters in peptide synthesis... 

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