Synthesis and structure-activity relationships of pyrazine-2-carboxamide derivatives as novel echinoderm microtubule-associated protein-like 4 (EML4)-anaplastic lymphoma kinase (ALK) inhibitors

Echinoderm microtubule-associated protein-like 4 (EML4)-anaplastic lymphoma kinase (ALK) is a valid therapeutic target for the treatment of EML4-ALK-positive non-small cell lung cancer (NSCLC). We discovered 12c as a novel and potent EML4-ALK inhibitor through structural optimization of 5a. In mice xenografted with 3T3 cells expressing EML4-ALK, oral administration of 12c demonstrated potent antitumor activity. This article describes the synthesis and biological evaluation of pyrazine-2-carboxamide derivatives along with studies of their structure-activity relationship (SAR) using computational modeling.