6,7-dimethoxyquinazolines and therapeutic use thereof

A compound of the formula:

• wherein:
• Ra is iodo, (C1-C4)hydroxyalkyl, OCF3, SCF3, SO3H, SO2F, NR2R4 where R2 is hydrogen or (C1-C4)alkyl and R4 is phenyl;
• or a group of the formula:
• wherein R5 is (C1-C4)alkyl, or (C1-C4) perfluoroalkyl, and R6 is hydrogen, (C1-C4)alkyl, or (C1-C4) perfluoroalkyl, and R7 is hydrogen, halo, hydroxy, (C1-C4)alkyl, (C1-C4)alkoxy, (C1-C4)hydroxyalkyl, or N(R2)2, where R2 is hydrogen or (C1-C4)alkyl;
• n is an integer of 1-4;
• Rb is each, independently, halo, hydroxy, mercapto, (C1-C4)alkyl, (C1-C4)alkoxy, (C1-C4)thioalkyl, (C1-C4)hydroxyalkyl, nitro, cyano, COCH3,CF3, OCF3, SCF3COOH, SO3H, SO2F, phenyl, or phenyl substituted by a group selected from halo, hydroxy, mercapto, (C1-C4)alkyl, (C1-C4) alkoxy, (C1-C4)thioalkyl, (C1-C4)hydroxyalkyl, amino, nitro, cyano, CF3, COOH, SO3H, SO2F;
• benzyloxy or benzyloxy substituted on the phenyl portion by a group defined above;
• NR2R3 where R2 is H or (C1-C4)alkyl and R3 is H, (C1-C4)alkyl, phenyl, or phenyl substituted by a group as defined above;
• and
• R1 is (C1-C4)alkyl or a pharmaceutically acceptable acid solution salt thereof.