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Directed C(sp3)-H arylation of tryptophan: transformation of the directing group into an activated amide.

ABSTRACT: The 8-aminoquinoline (8AQ) directed C(sp3)-H functionalization was applied in the synthesis of ?-arylated tryptophan derivatives. The laborious protecting group reorganization towards ?-amino acids compatible for solid phase peptide synthesis (SPPS) was cut short by the transformation of the directing group into an activated amide, which was either used directly in peptide coupling or in the gram scale synthesis of storable Fmoc-protected amino acids for SPPS. In this work, directed C-H activation and nonplanar amide chemistry complement each other for the synthesis of hybrids between phenylalanine and tryptophan with restricted side chain mobility.

SUBMITTER: Nicke L

PROVIDER: S-EPMC6844298 | biostudies-literature | 2019 Oct

REPOSITORIES: biostudies-literature

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Directed C(sp3)-H arylation of tryptophan: transformation of the directing group into an activated amide.

Nicke Lennart L Horx Philip P Harms Klaus K Geyer Armin A

Chemical science 20190808 37

The 8-aminoquinoline (8AQ) directed C(sp3)-H functionalization was applied in the synthesis of β-arylated tryptophan derivatives. The laborious protecting group reorganization towards α-amino acids compatible for solid phase peptide synthesis (SPPS) was cut short by the transformation of the directing group into an activated amide, which was either used directly in peptide coupling or in the gram scale synthesis of storable Fmoc-protected amino acids for SPPS. In this work, directed C ...[more]

PMID: 31803437

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