NITROGENOUS HETEROCYCLIC CARBOXAMIDE DERIVATIVES OR SALTS THEREOF AND ANTIVIRAL AGENTS CONTAINING BOTH

摘要

Nitrogenous heterocyclic carboxamide derivatives represented by general formula (I), or salts thereof are useful as preventives and therapeutic agen ts for infections with viruses, particularly influenza virus. In said formula A is an optionally substituted pyrazine, pyrimidine, pyridazine or triazine ring; R1 is O or OH; R2 is hydrogen, acyl, or optionally substituted carbamoylalkyl or carboxyalkyl; and the broken line represents a single or double bond.