Photocleavable 2-nitrobenzylamino anchored polystyrene-butanediol dimethacrylate supports for the synthesis of protected peptides, peptide amides and peptide N-alkyl amides

2-Nitrobenzylamino-type anchoring groups were incorporated on 2% butanediol dimethacrylate cross-linked polystyrene support. The resultant photolabile polymeric supports were used for the synthesis of fully protected peptides and their final cleavage as C-terminal peptide acids, peptide amides and peptide N-alkyl amides by photolysis under mild neutral conditions. The photosensitive chromophore has a dual function of serving as an anchoring linkage between the support and the growing peptide chain and as a latent reagent for the conversion of a C-terminal carboxyl group into the modified form during photolytic cleavage. The C-terminal modified peptides were obtained by irradiating the peptidyl resin in a TFE/DCM mixture at 350 nm. The efficacy of the new resin is illustrated by synthesizing the protected derivatives of the peptides in very high yield and purity. The identity of the peptides was checked by amino acid analysis, TLC and MALDI TOF MS.