Convergent approaches, SPPS

For N -protection in SPPS the Nps group has not found general application, despite some early attempts.b l It could, however, represent an interesting approach for the linkage of the first amino acid to the solid support,t since esterification of hydroxymethylated resin with Nps-Phe-OH by DCC/DMAP occurs without racennization.t Interesting use of this protection has been reported in convergent SPPS and solution synthesis. 

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