A methyl ketone that is 2-butanone in which one of the methyl hydrogens at position 4 is replaced by a 6-methoxy-2-naphthyl group. A prodrug that is converted to the active metabolite, 6-methoxy-2-naphthylacetic acid, following oral administration. It is shown to have a slightly lower risk of gastrointestinal side effects than most other non-steroidal anti-inflammatory drugs.