121-34-6 3-Methoxy-4-hydroxybenzoic acid 4-10-00-01459 (Beilstein Handbook Reference) 4-HYDROXY-3-METHOXYBENZOIC ACID AI3-19542 Acide vanillique BRN 2208364 Benzoic acid, 4-hydroxy-3-methoxy- EINECS 204-466-8 NSC 3987 NSC 674322 Protocatechuic acid, 3-methyl ester VA VA (VAN) Vanillic acid m-Anisic acid, 4-hydroxy- p-Vanillic acid