5-Aminopyridazine-4-carboxylic acid
Product Specifications
- CAS
- 21579-37-3
- MF
- C5H5N3O2
- Appearance
- yellow to off-white solid
- Synonym(s)
- 4-Pyridazinecarboxylic acid, 5-amino-; 5-Amino-4-pyridazinecarboxylic Acid
- Shipping
- ambient temperature
- Storage
- 2-8°C
5-Aminopyridazine-4-carboxylic acid has the verified formula C5H5N3O2 and CAS reference 21579-37-3. The corresponding PubChem entry is CID 21817856. Its bonding pattern is written as SMILES C1=C(C(=CN=N1)N)C(=O)O, and the structure-derived key is AKPRYFURIIOSPV-UHFFFAOYSA-N. Formula, CAS, CID, and connectivity notation converge on one defined chemical identity.
The pyridazine core contains two adjacent ring nitrogen atoms. An amino group occupies position 5, immediately beside the carboxylic acid substituent at position 4. Within C5H5N3O2, two oxygen atoms form the carboxylic acid group, two nitrogens belong to the heteroaromatic ring, and the third nitrogen belongs to the amino substituent. The official graph contains a single connected component and does not append a separate counterion. The acid carbon contributes the fifth carbon outside the four-carbon portion of the diazine ring.
Both ring locants are necessary to preserve the relationship between the amino and carboxyl groups. A formula search alone cannot distinguish this arrangement from another aminopyridazine carboxylic acid isomer. CID 21817856 records the precise graph, while SMILES C1=C(C(=CN=N1)N)C(=O)O exposes the adjacent substitution directly. InChIKey AKPRYFURIIOSPV-UHFFFAOYSA-N adds a portable exact-match reference, and CAS 21579-37-3 connects the same identity to its numeric designation. The combined evidence fixes the 5-amino and 4-carboxylic acid positions without relying on an abbreviated or position-free compound label.