Naphthol AS is an organic compound with the formula C10H6(OH)C(O)NHC6H5.

Many analogous compounds are known, designated with a differing suffix.

For example, in Naphthol AS-OL, the aryl substituent on nitrogen is C6H4-2-OCH3.

These compounds are used as coupling partners in the preparation of some azo dyes.

[1] In 1911, it was found to be a good precursor to dyes for wool by chemists at K. Oehler Anilin- und Anilinfarbenfabrik Offenbach.