Polymer-supported synthesis of protected peptide segments on a photosensitive o-nitro(a-methyl)bromobenzyl resin

Abstract

The preparation of a new polystyrene support containing the photodetachable o-nitro(α -methyl)benzyl anchoring group and its application in the solid phase synthesis of fully protected C-terminal peptides are described, The preparation of the photosensitive resin involves a 4-step polymer-analogous reaction starting from 1 %-divinyl benzene crosslinked polystyrene. Amino acid units were incorporated into this resin following standard solid phase peptide synthetic methodology and the peptides were cleaved from the support by photolysis under neutral conditions at 350 nm, in 40-50 % overall yield. The attachment of the peptide through a secondary ester linkage In o-position to the nitro group is the factor permitting the photolytic cleavage of the peptides from the support.