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Direct palladium-mediated on-resin disulfide formation from Allocam protected peptides.

ABSTRACT: The synthesis of disulfide-containing polypeptides represents a long-standing challenge in peptide chemistry, and broadly applicable methods for the construction of disulfides are in constant demand. Few strategies exist for on-resin formation of disulfides directly from their protected counterparts. We present herein a novel strategy for the on-resin construction of disulfides directly from Allocam-protected cysteines. Our palladium-mediated approach is mild and uses readily available reagents, requiring no special equipment. No reduced peptide intermediates or S-allylated products are observed, and no residual palladium can be detected in the final products. The utility of this method is demonstrated through the synthesis of the C-carboxy analog of oxytocin.

SUBMITTER: Kondasinghe TD

PROVIDER: S-EPMC5475270 | biostudies-literature | 2017 Apr

REPOSITORIES: biostudies-literature

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Direct palladium-mediated on-resin disulfide formation from Allocam protected peptides.

Kondasinghe Thilini D TD Saraha Hasina Y HY Odeesho Samantha B SB Stockdill Jennifer L JL

Organic & biomolecular chemistry 20170401 14

The synthesis of disulfide-containing polypeptides represents a long-standing challenge in peptide chemistry, and broadly applicable methods for the construction of disulfides are in constant demand. Few strategies exist for on-resin formation of disulfides directly from their protected counterparts. We present herein a novel strategy for the on-resin construction of disulfides directly from Allocam-protected cysteines. Our palladium-mediated approach is mild and uses readily available reagents, ...[more]

PMID: 28327729

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