CAS: 99-50-3 Molecular Formula: C7H6O4 Molecular Weight (g/mol): 154.121 MDL Number: MFCD00002509 InChI Key: YQUVCSBJEUQKSH-UHFFFAOYSA-N Synonym: protocatechuic acid,4-carboxy-1,2-dihydroxybenzene,protocatehuic acid,benzoic acid, 3,4-dihydroxy,protocatechuate,4,5-dihydroxybenzoic acid,3,4-dihydroxybenzoicacid,unii-36r5qj8l4b,ccris 6291,chembl37537 PubChem CID: 72 ChEBI: CHEBI:36062 IUPAC Name: 3,4-dihydroxybenzoic acid SMILES: C1=CC(=C(C=C1C(=O)O)O)O