Evaluation of the trifluoromethanosulfonic acid/trifluoroacetic acid/thioanisole cleavage procedure for application in solid-phase peptide synthesis

• Autor(a) principal: Jubilut, Guita Nicolaewsky [UNIFESP]
• Data de Publicação: 2001
• Outros Autores: Cilli, Eduardo Maffud [UNIFESP], Tominaga, Mineko [UNIFESP], Miranda, Antonio [UNIFESP], Okada, Yoshio, Nakaie, Clovis Ryuichi [UNIFESP]
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Repositório Institucional da UNIFESP
• Texto Completo: http://dx.doi.org/10.1248/cpb.49.1089; http://repositorio.unifesp.br/handle/11600/26617
• topic: peptide synthesise; peptidyl-resin cleavage; trifluoromethanesulfonic acid; 4-(oxymethyl)-phenylacetamidomethyl-resin; benzhydrylamine-resin; methylbenzhydrylamine-resin

As an extension of our investigation of peptidyl-resin linkage stability towards different cleavage procedures used in the solid-phase peptide synthesis (SPPS) technique, the present paper evaluated the trifluoromethanesulfonic acid (TFMSA)/trifluoroacetic acid (TFA)/thioanisole method, varying the type of resin (benzhydrylamine-resin, BHAR; methylbenzhydrylamine-resin, MBHAR and 4-(oxymethyl)-phenylacetamidomethyl-resin, PAMR) and peptide resin-bound residue (Gly and Phe). the vasoactive angiotensin II (AII, DRVYIHPF) and its /Gly(8)/-AII analogue linked to those resins used routinely in tert-butyloxycarbonyl (Boc)-SPPS chemistry were submitted comparatively to a time course study towards TFMSA/TFA cleavage. At VC, /Gly(8)/-AII was completely removed from all resins in less than 6 h, but the hydrophobic Plies moiety-containing All sequence was only partially cleaved (not more than 15%) from BHAR or MBHAR in this period. At 25 degreesC, /Gly(8)/-AII cleavage time decreased to less than 2 h irrespective of the solid support. and quantitative removal of All from PAMR and MBHAR occurred in less than 3 h. However, about 10-15 h seemed to be necessary for cleavage of All from BHAR, and in this extended cleavage reaction a significant increase in peptide degradation rate was observed. Regardless of the cleavage temperature used, the decreasing order of acid stability measured for resins was BHAR > MBHAR > PAMR. Collectively, these findings demonstrated the feasibility of applying TFMSA/TFA solution as a substitute for anhydrous HF at the cleavage step in Boc-SPPS methodology. Care should be taken however, as the cleavage efficacy depends on multiple factors including the resin, peptide sequence. the time and temperature of reaction.