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Synthesis of protected norcysteines for SPPS compatible with Fmoc-strategy.

ABSTRACT: We report the synthesis of racemic Alloc-Ncy(Tmob)-OH, the resolution of its methyl ester, and demonstrate its application to form a norcystine bridge in octreotide-amide using the Fmoc-strategy on solid phase. N-Alloc and S-Tmob protections of norcysteine (Ncy) were found to be a preferred choice for Fmoc-strategy over three other protected norcysteines synthesized i.e. Fmoc-Ncy(tBu)-OH, Alloc-Ncy(tBu)-OH and Alloc-Ncy(Trt)-OH.

SUBMITTER: Samant MP

PROVIDER: S-EPMC2701708 | biostudies-literature | 2007 Jul

REPOSITORIES: biostudies-literature

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Synthesis of protected norcysteines for SPPS compatible with Fmoc-strategy.

Samant Manoj P MP Rivier Jean E JE

Tetrahedron letters 20070701 29

We report the synthesis of racemic Alloc-Ncy(Tmob)-OH, the resolution of its methyl ester, and demonstrate its application to form a norcystine bridge in octreotide-amide using the Fmoc-strategy on solid phase. N-Alloc and S-Tmob protections of norcysteine (Ncy) were found to be a preferred choice for Fmoc-strategy over three other protected norcysteines synthesized i.e. Fmoc-Ncy(tBu)-OH, Alloc-Ncy(tBu)-OH and Alloc-Ncy(Trt)-OH. ...[more]

PMID: 19562100

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