Synthesis and comparative properties of two amide-generating resin linkers for use in solid phase peptide synthesis
Fang-Kun Deng1, Kalyaneswar Mandal, Sam Luisier
1Department of Chemistry, University of Chicago, Chicago, IL 60615, USA. dengprotein@uchicago.edu
Abstract:
Well-characterized resins of high purity are critical for effective solid phase peptide synthesis (SPPS). The quality of commercial (4-methyl)benzhydrylamine-resin (MBHA-resin), used for the synthesis of peptide amides, is not consistent and residual ketone functionalities are frequently present. Such ketone or aldehyde impurities lead to the formation of acylation-resistant deletion peptides in SPPS. To avoid these undesirable side reactions, we have optimized the preparation of two amide-generating linkers, which, in combination with aminomethyl-resin prepared directly from polystyrene resin, serve as alternatives to MBHA-resin for peptide amide synthesis. Then we have explored their comparative properties in SPPS. Use of sonication in reductive amination facilitated the synthesis of both benzhydrylamine (BHA) and MBHA linkers.
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