Biologically inspired one-pot access routes to 4-hydroxybenzothiazole amino acids, red hair-specific markers of UV susceptibility and skin cancer risk

The first practical access to 4-hydroxy-6-(2-amino-2-carboxyethyl)benzothiazole and 4-hydroxy-7-(2-amino-2-carboxyethyl)benzothiazole (1b and 2b) and the corresponding 2-carboxy-derivatives 1a and 2a is reported, involving one-pot sequential Zn2+-assisted biomimetic oxidation of l-dopa and l-cysteine, 5-S-cysteinyldopa or 2-S-cysteinyldopa.