Carboxylic Acid, Carboxylic Acid Salt, Carboxylic Acid Anhydride, Or Carboxylic Acid Halide Patents (Class 504/320)
- Nitrogen, other than as nitro or nitroso, attached directly or indirectly to the benzene ring by nonionic bonding (Class 504/322)
- Oxygen is bonded directly to the benzene ring and is part of an acyclic chain between the benzene ring and a -C(=O)O- group (e.g., 2,4-dichlorophenoxyacetic acids, etc.) (Class 504/323)
- The benzene ring is bonded directly to the carbon of a -C(=O)O- group (e.g., benzoic acids, etc.) (Class 504/324)