Peptide synthesis. II. Convenient synthesis of p-nitrobenzyl esters of amino acids and peptides

Theodoropoulos, D; Tsangaris, J

dc.contributor.author	Theodoropoulos, D	en
dc.contributor.author	Tsangaris, J	en
dc.date.accessioned	2014-03-01T01:37:39Z
dc.date.available	2014-03-01T01:37:39Z
dc.date.issued	1964	en
dc.identifier.issn	00223263	en
dc.identifier.uri	https://dspace.lib.ntua.gr/xmlui/handle/123456789/21601
dc.relation.uri	http://www.scopus.com/inward/record.url?eid=2-s2.0-33947487399&partnerID=40&md5=14ad10f64b3a5d7cb3bd9c026e4114fa	en
dc.title	Peptide synthesis. II. Convenient synthesis of p-nitrobenzyl esters of amino acids and peptides	en
heal.type	journalArticle	en
heal.publicationDate	1964	en
heal.abstract	p-Nitrobenzyl tosylate undergoes ready nucleophilic attack with displacement of the (-OSO2C6H4CH3)- ion when it is treated with the sodium or trialkylammonium salt of carbobenzoxyamino acids and peptides. The yields of p-nitrobenzyl esters thus prepared are consistently better than 70%. Included are the p-nitrobenzyl esters of carbobenzoxyglycine, carbobenzoxy-L-phenylalanine, and carbobenzoxy-L-threonine, and the dipeptide esters of carbobenzoxyglycyl-L-leucine and carbobenzoxy-L-prolyl-L-phenylalanine. By use of this procedure, N-tritylglycine and N-trityl-L-tryptophan were converted into the corresponding p-nitrobenzyl esters. Detritylation of the latter by mild acid solvolysis afforded the respective p-nitrobenzyl esters of glycine and L-tryptophan, both isolated as the p-toluenesulfonates. Similarly, the tripeptide derivative, N(im)-benzyl-L-histidylL-prolyl-L-phenylalanine p-nitrobenzyl ester di-p-toluenesulfonate, was prepared. Esterification of the C-terminal carboxyl end proceeded, in all cases tested, with no detectable amount of racemization.	en
heal.journalName	Journal of Organic Chemistry	en
dc.identifier.volume	29	en
dc.identifier.issue	8	en
dc.identifier.spage	2272	en
dc.identifier.epage	2275	en