Patent ID: 7247632

Claim:
A compound of formula (I): wherein: a. R 1 is aryl, optionally substituted with one or more hydrogen, halo, cyano, hydroxy, carboxy, keto, thioketo, amino, acylamino, acyl, amido, phenyl, aryloxy, alkyl, alkenyl, alkynyl, heteroalkyl, haloalkyl, alkoxy, aryl, cycloalkyl, spirocycloalkyl or combinations thereof; b. each R 2 is independently chosen from hydrogen, halo, cyano, hydroxy, carboxy, keto, thioketo, amino, acylamino, acyl, amido, phenyl, aryloxy, alkyl, alkenyl, alkynyl, beteroalkyl, haloalkyl, alkoxy, aryl, and cycloalkyl; c. R 3 and R 4 , together with the nitrogen atom to which they are bonded, join to form a piperazine ring substituted with a pyridazine ring or one or more hydrogen, halo, cyano, hydroxy, carboxy, keto, thioketo, amino, acylamino, acyl, amido, alkyl, alkenyl, alkynyl, heteroalkyl, haloalkyl, alkoxy, or combinations thereof; and d. R 5 and R 6 are each independently chosen from hydrogen, halo, cyano, hydroxy, carboxy, keto, thioketo, amino, acylamino, acyl, amido, phenyl, aryloxy, alkyl, alkenyl, alkynyl, heteroalkyl, haloalkyl, alkoxy, aryl, and cycloalkyl; or optical isomers, diastereomers and enantiomers of the formula above, or a pharmaceutically-acceptable salt thereof.