PURPOSE: To provide the new compounds useful as antiviral agents.
CONSTITUTION: The compounds are those represented by the formula I [R1 is H or a 1-8C alkyl group; R2 is H, a formyl, methyl, benzyl group, or the like; R3 is H, a carboxyl, 3-8C cycloalkyl, 1-8C alkoxycarbonyl group or the like; and R4 is a 1,4-diazacycloheptanyl group than is joined through an N atom or the like, or a compound represented by the formula II or III ((o) is 2 or 3; D is -CH2 or O; and R8 is H or a methyl or ethyl group) or the like], such as ethyl 9,10-difluoro-2-ethoxycarbonyl-7-oxo-7H-pyrido[1,2,3- de][1,4]benzoxazine-6-carboxylate. Such a compound represented by the formula I is prepared by reacting a compound represented by the formula IV (T is a halogen) with a compound represented by the formula R4-H in an inert solvent, in the presence of a base and in a protective gas atmosphere.
MARUTEIN RUPERUTO
MIHIYAERU SHIYURIIBAA
TOOMASU JIEI SHIYURUTSUE
RAINAA NOIMAN
