1,4-dihydropyridine and 1,4-dihydropyrane derivatives and novel cosmetic or dematological sunscreen compositions containing novel and/or known 1,4-dihydropyridine or 1,4-dihydropyrane derivatives which are useful for photoprotecting human skin and/or hair against UV radiation, in particular solar radiation, and the use of such 1,4-dihydropyridine and/or 1,4-dihydropyrane derivatives as UV-A screening agents, particularly in cosmetic and pharmaceutical compositions.