Pyrrolo[3,2-c]quinoline compounds as CK2 inhibitors

A method of inhibiting CK2 enzyme activity in a patient, comprising administering to a patient in need thereof a therapeutically effective amount of a compound having the formula I:

• or a pharmaceutically acceptable salt, stereoisomer, or solvate thereof, wherein:
• R1 and R4 are independently selected from the group consisting of hydrogen, C1-C6 straight chained alkyl, C1-C6 branched alkyl, and C3-C6 cycloalkyl;
• R2 is selected from the group consisting of hydrogen, halogen, C1-C6 straight chained alkyl, C1-C6 branched alkyl, halo-C1-C6 straight chained alkyl, halo-C1-C6 branched alkyl, and —Ar;
• R3 is selected from the group consisting of —NHAr, —NHCH2Ar, —NHCH2CH2Ar, —NHCOAr, —NHSO2Ar, —NHCH2CH2NHR7, —NHCH2CH2NR7R8, —NHCH2CH2CH2NHR7, —NHCH2CH2CH2NR7R8, —NHCOCH2CH2NHR7, —NHCOCH2CH2NR7R8, —NHCOCH2CH2CH2NHR7, —NHCOCH2CH2CH2NR7R8, —NHSO2CH2CH2NHR7, —NHSO2CH2CH2NR7R8, —NHSO2CH2CH2CH2NHR7, —NHSO2CH2CH2CH2NR7R8, —Ar, —CH2Ar, —CH2CH2Ar, —COAr, —SO2Ar, —CH2CH2NHR7, —CH2CH2NR7R8, —CH2CH2CH2NHR7, —CH2CH2CH2NR7R8, —COCH2CH2NHR7, —COCH2CH2NR7R8, —COCH2CH2CH2NHR7, —COCH2CH2CH2NR7R8, —SO2CH2CH2NHR7, —SO2CH2CH2NR7R8, —SO2CH2CH2CH2NHR7, —SO2CH2CH2CH2NR7R8, C1-C6 straight chained alkyl, C1-C6 branched alkyl, C3-C6 cycloalkyl, halo-C1-C6 straight chain alkyl, halo-C1-C6 branched alkyl, halo-C3-C6 cycloalkyl, cyano-C1-C6 straight chain alkyl, cyano-C1-C6 branched alkyl, and cyano-C3-C6 cycloalkyl;
• Ar is an aryl ring or a 5 or 6 membered heteroaryl ring, either of the aryl ring or the heteroaryl ring being optionally substituted with one or more substituents selected from the group consisting of halogen, cyano, —OH, —OR5, —NH2, —NHR5, —NR5R6, —CONH2, —CONHR5, —CONR5R6, —SO2NH2, —SO2NHR5, —SO2NR5R6, —NHCOR5, —NHCO2R5, —NHCONHR5, —NHSO2NHR5, —NHSO2R5, —COR5, —CO2R5, C1-C6 straight chained alkyl, C1-C6 branched alkyl, C3-C6 cycloalkyl, halo-C1-C6 straight chain alkyl, halo-C1-C6 branched alkyl, halo-C3-C6 cycloalkyl, cyano-C1-C6 straight chain alkyl, cyano-C1-C6 branched alkyl, and cyano-C3-C6 cycloalkyl;
• R5 and R6 are each independently selected from the group consisting of hydrogen, C1-C6 straight chain alkyl, C1-C6 branched alkyl, C3-C6 cycloalkyl, halo-C1-C6 straight chain alkyl, halo-C1-C6 branched alkyl, halo-C3-C6 cycloalkyl, cyano-C1-C6 straight chain alkyl, cyano-C1-C6 branched alkyl, and cyano-C3-C6 cycloalkyl;
• and
• R7 and R8 are each independently selected from the group consisting of hydrogen, C1-C6 straight chain alkyl, C1-C6 branched alkyl, C3-C6 cycloalkyl, halo-C1-C6 straight chain alkyl, halo-C1-C6 branched alkyl, halo-C3-C6 cycloalkyl, cyano-C1-C6 straight chain alkyl, cyano-C1-C6 branched alkyl, and cyano-C3-C6 cycloalkyl or wherein R7 and R8, together with a nitrogen atom to which they are attached, form a nitrogen-containing heterocycle, such nitrogen-containing heterocycle being optionally substituted with from one to three substituents independently selected from the group consisting of a straight or branched C1-C6 alkyl group, a halogen atom, a straight or branched C1-C6 alkoxy group, a straight or branched C1-C6 trihaloalkyl group, and a hydroxy group.