Cyanoisoquinoline compounds and methods of use thereof

A method for inhibiting a HIF hydroxylase in a subject, the method comprising administering to the subject a compound of formula I:

• wherein:
• R is selected from the group consisting of hydrogen, alkyl, and substituted alkyl;
• R1, R2, R3 and R4 are independently selected from the group consisting of hydrogen, halo, cyano, hydroxyl, alkyl, substituted alkyl, aryl, substituted aryl, heteroaryl, substituted heteroaryl, amino, substituted amino, —OR7, —SR7, —SOR7, and —SO2R7 wherein R7 is selected from the group consisting of alkyl, substituted alkyl, cycloalkyl, substituted cycloalkyl, aryl, substituted aryl, heteroaryl, and substituted heteroaryl;
• R5 and R6 are independently selected from the group consisting of hydrogen and C1-3 alkyl;
• or a pharmaceutically acceptable salt, tautomer, or stereoisomer thereof;
• or an ester or amide of the carboxylic acid moiety on the glycine or alanine-based substituent of the cyanoisoquinoline ring.