How is Ethyl 4-hydroxy-6-methoxy-3-quinolinecarboxylate (CAS: 77156-78-6) typically synthesized?

Ethyl 4-hydroxy-6-methoxy-3-quinolinecarboxylate (CAS: 77156-78-6) can be synthesized through a multistep process involving the protection of a carboxylic acid, subsequent substitution reactions, and deprotection. Commonly, this involves protecting the carboxylic acid with an acylating agent, followed by a nucleophilic substitution reaction with a 4-hydroxy-6-methoxy-3-quinoline methyl ether. The process typically yields a clean product with high selectivity and reasonable to good yields.