Vn. Medvedkin et al., P-SULFOTETRAFLUOROPHENYL HYDROPHILIC ACTI VE ESTERS OF AMINO-ACIDS INPEPTIDE-SYNTHESIS, Bioorganiceskaa himia, 21(9), 1995, pp. 684-690
Highly reactive hydrophilic (i.e., water-soluble) p-sulfotetrafluoroph
enyl esters (Tfs esters) are proposed for peptide synthesis in aqueous
and aqueous-organic media, as well as for protein and peptide partial
synthesis in an aqueous medium. These esters can serve as a basis for
creating a series of protein modifying reagents. As they are analogs
of the widely used pentafluorophenyl esters, the Tfs esters possess a
high reactivity coupled with good stability during storage. The expres
sion for the reaction rate (for substrates AA(1) and AA(2)) is shown t
o be v = k[Boc-AA(1)-OTfs][H-AA(2)-NH2](0.5) for both water and DMF, i
.e., the reaction is not a simple second-order reaction. The reaction
rate in water is only slightly lower than that in DMF.