COUMARIN DERIVATIVES WITH COMT INHIBITING ACTIVITY

摘要

Compounds of formula (I') wherein the two OH- substituents in the phenyl moiety are in a position ortho to one another and R1 in a position ortho to one of the hydroxy groups; and X, R1 to R6 are as defined in claims, exhibit COMT enzyme inhibiting activity so that they are useful as COMT inhibitors.