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Updated: Oct 15, 2025
![Radiosynthesis of 1-2-[18F]Fluoroethyl-L-Tryptophan using a One-pot, Two-step Protocol](/_next/image?url=https%3A%2F%2Fcloudfront.jove.com%2FCDNSource%2Fteasers%2F63025.jpg&w=3840&q=50)
Radiosynthesis of 1-2-[18F]Fluoroethyl-L-Tryptophan using a One-pot, Two-step Protocol
Published on: September 21, 2021
Negishi Cross-Coupling Provides Alkylated Tryptophans and Tryptophan Regioisomers
Steffen Dachwitz1, Bjarne Scharkowski1, Norbert Sewald1
1Department of Chemistry, Organic and Bioorganic Chemistry, Bielefeld University, Universitätsstraße 25, 33615, Bielefeld, Germany.
Abstract:
Mild transition-metal catalysed cross-couplings enable direct functionalisation of biocatalytically halogenated tryptophans with alkyl iodides, representing a new alternative for late-stage derivatisations of halogenated aromatic amino acids. Moreover, this strategy enables preparation of (homo)tryptophan regioisomers in a simple two-step synthesis using a Pd-catalysed Negishi cross coupling. This method provides access to non-canonical constitutional surrogates of tryptophan, ready for use in peptide synthesis.
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