Pyrazine derivatives or salts thereof, pharmaceutical composition containing the same, and production intermediates thereof

摘要

Pyrazine derivatives represented by general formula [1]:wherein the variables are as defined in the specification, or salts thereof have an excellent antiviral activity and are useful as a therapeutic agent for treating viral infections. Further, fluoropyrazine-carboxamide derivatives represented by general formula [2]:wherein the variables are as defined in the specification, or salts thereof are useful as an intermediate for production of the compounds of general formula [1], and as an intermediate for production of the fluoropyrazine-carboxamide derivatives of which one typical example is 6-fluoro-3-hyroxy-2-pyrazine-carboxamide having an antiviral activity.