1079926-41-2

Upstream product

• 98-80-6 phenylboronic acid 
• 153-97-9 7-chloro-L-tryptophan 
• 75816-19-2 (S)-7-bromo-tryptophan 
• 73-22-3 L-Tryptophan 

Relevant academic research and scientific papers

Suzuki-Miyaura Diversification of Amino Acids and Dipeptides in Aqueous Media

The Suzuki-Miyaura derivatisation of free amino acids, peptides and proteins is an attractive area with considerable potential utility for medicinal chemistry and chemical biology. Here we report the modification of unprotected and Boc-protected aromatic amino acids and dipeptides in aqueous media, enabling heteroarylation and vinylation. We systematically investigate the impact of the peptide backbone and adjacent amino acid residues upon the reaction. Our studies reveal that although asparagine and histidine hinder the reaction, by utilising dppf, a ferrocene-based bidentate phosphine ligand, cross coupling of halophenylalanine or halotryptophan adjacent to such a residue could be enabled. Our studies reveal dppf to have good compatibility with all unprotected, proteinogenic amino acid side chains.

Modular Combination of Enzymatic Halogenation of Tryptophan with Suzuki-Miyaura Cross-Coupling Reactions

The combination of the biocatalytic halogenation of l-tryptophan with subsequent chemocatalytic Suzuki-Miyaura cross-coupling reactions leads to the modular synthesis of an array of C5, C6, or C7 aryl-substituted tryptophan derivatives. In a three-step one-pot reaction, the bromo substituent is initially incorporated regioselectively by immobilized tryptophan 5-, 6-, or 7-halogenases, respectively, with concomitant cofactor regeneration. The halogenation proceeds in aqueous media at room temperature in the presence of NaBr and O2. After the separation of the biocatalyst by filtration, a Pd catalyst, base, and boronic acid are added to the aryl halide formed in situ to effect direct Suzuki-Miyaura cross-coupling reactions followed by tert-butoxycarbonyl (Boc) protection. After a single purification step, different Boc-protected aryl tryptophan derivatives are obtained that can, for example, be used for peptide or peptidomimetic synthesis. Putting the pieces together: By combining the enzymatic halogenation of l-tryptophan using flavin adenine dinucleotide dependent halogenases with Pd-catalyzed Suzuki-Miyaura cross-coupling reactions in water, the C5-, C6-, or C7-position of the indole ring can be brominated regioselectively in situ and functionalized chemocatalytically in a stepwise one-pot reaction.

Gene expression enabling synthetic diversification of natural products: Chemogenetic generation of pacidamycin analogs

Introduction of prnA, the halogenase gene from pyrrolnitrin biosynthesis, into Streptomyces coeruleorubidus resulted in efficient in situ chlorination of the uridyl peptide antibotic pacidamycin. The installed chlorine provided a selectably functionalizable handle enabling synthetic modification of the natural product using mild cross-coupling conditions in crude aqueous extracts of the culture broth.

Development of fluorescent aryltryptophans by Pd mediated cross-coupling of unprotected halotryptophans in water

A convenient and high yielding procedure for the Suzuki-Miyaura cross-coupling of unprotected bromo- and chlorotryptophans in water provides fluorescent aryltryptophans. The Royal Society of Chemistry.