How is 4-Amino-5-(ethylsulfanyl)-2-methoxybenzoic acid (CAS: 71675-86-0) typically synthesized?

4-Amino-5-(ethylsulfanyl)-2-methoxybenzoic acid is typically synthesized via a multi-step procedure involving the protection of the hydroxyl group of 2-methoxybenzoic acid followed by sulfenylation with ethanethiol, followed by deprotection and amidation. Key reagents include 4-nitrotoluene, ethanethiol, and sodium hydroxide. The yield is around 70-75%, and the reaction is conducted under basic conditions.