Rhodium-Catalyzed Regioselective C7Ar-(Acyl)alkylation of Tryptophan With Allyl Alcohols and Its Late-Stage Peptide
Disha Harsukhbhai Tank1, Somnath Arjun Borade1, Mukul Yadav1
1Department of Chemistry, Birla Institute of Technology and Science, Pilani, Rajasthan, India.
Abstract:
An efficient Rh(III)-catalyzed pivaloyl-directed strategy has been developed for the C7Ar-(acyl)alkylation of tryptophans with substituted and unsubstituted allyl alcohols, delivering tryptophan-based unnatural amino acids without compromising their chirality. The disclosed methodology showcased high tolerance of neutral, acidic, and basic amino acids, including Gly, Ala, Val, Leu, Phe, Pro, Asp, Lys, and Thr units, enabling regioselective late-stage functionalization of tryptophan units in a variety of tryptophan-containing dipeptides, tripeptides in reasonable yields.
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