Using an RAE derived from a dipeptide, UAA 25 was isolated in 36%, thus opening possibilities for late-stage functionalization of small proteins. Single-crystal X-ray crystallography of 25 confirmed its structure, hence highlighting that the developed method is a useful strategy to retain the α-stereocentre. Finally, using the six-reactors carousel, this methodology can be scaled up to 3 grams of starting material in one batch, as demonstrated with compound 13 isolated in 1.2 grams (49% yield). Scheme 2. Synthesis of UAAs by means of electrochemical lateral-chain decarboxylative arylations. In brackets isolated yield after two purifications by flash chromatography.