HETEROCYCLIC COMPOUNDS AND CEREBRAL FUNCTION IMPROVERS CONTAINING THE SAME AS THE ACTIVE INGREDIENT

摘要

Heterocyclic compounds represented by the general formula (I): (I) wherein the skeleton (II) is a structure of formula (III) or (IV) or the like: (II) (III) (IV) R1 is hydrogen, C1-6 alkyl, or benzyloxy; R2 is methyl or nil; R3 is hydrogen, C1-6 alkyl, C2-6 alkenyl, C3-8 cycloalkyl, or -CH2R5 [wherein R5 is phenyl (which may be substituted with C1-6 alkyl, halogeno, or cyano) or thienyl]; and R4 is C1-6 alkyl, C2-6 alkenyl, C3-8 cycloalkyl, or -CH2R6 [wherein R6 is phenyl (which may be substituted with C1-6 alkyl, halogeno, or cyano), naphthyl, or thienyl], or alternatively R3 and R4 may be united.