Abstract: Cosmetic sunscreen products which contain a tyrosine derivative of the formula: ##STR1## in which R.sub.1 is H or CH.sub.3 --(CH.sub.2).sub.x, with X being 1 to 20, and R.sub.2 is CH.sub.3 CO-- or CH.sub.3 --(CH.sub.2).sub.y --CO, with Y being 1 to 20, provide a long lasting and dark, natural tan after a short exposure to sunlight. The sunscreen product may contain an activator which is an alkali metal or alkaline earth metal salt of adenosine-5'-tri-, di-, or monophosphoric acid and mixtures thereof with an alkali metal or alkaline earth metal hydrogen phosphate.