Abstract: Radical halogenation of protected L-tryptophan, and of related indoles, leads to the corresponding 2-halo derivatives in high yield: enzymatic removal of the blocking groups provides the new amino acid analogues. In the concentration range 0.01-3.0 M HC104, hydrolysis to oxindoles of the fully protected 2-halotryptophans, as well as of 2-halo-3-(R)- indoles in general (R= CH3, CH, CO, Et, CH2CH2C02Me), increases linearly with acidity ( ...
