NEW HETEROCYCLIC COMPOUNDS, PRODUCTION AND USE THEREOF

摘要

A compound having the formula (I) or (II) , wherein R<1> is a hydrogen atom or an organic residue bonded via a carbon atom, R<2> is a hydrogen atom or a N protecting group, -COR<3> is an optionally esterified or amidated carboxyl group, R<4> and R<5> are, the same or different, respectively a hydrogen atom or an acyl group or a chained or alicyclic hydrocarbon group optionally having an aryl substituent, R<6> is NOH or O, n is an integer of 0 to 3, or R<4> and R<5> together with the adjacent nitrogen atom may form a ring or an optionally substituted benzylidene amino group, which is useful therapeutics of brain dysfunction.