Kinase inhibitors and related methods of use

A compound of formula (II), or a pharmaceutically acceptable salt thereof:

• wherein:
• R2 is selected from the group consisting of C1-C6 alkyl, substituted aryl and optionally substituted heteroaryl;
• R3 is hydrogen;
• R4 and R5 together form an oxo group;
• R6 is selected from the group consisting of hydrogen and —(CRaRb)n—X;
• R7 is selected from the group consisting of hydrogen and —(CRaRb)n—X;
• each Ra and Rb is independently selected from the group consisting of hydrogen and C1-C4 alkyl;
• n is 1, 2, 3, 4, 5 or 6;
• each X is independently selected from the group consisting of optionally substituted aryl, optionally substituted heteroaryl, —ORc, —CORd, —COORe, —CON(Rf)(Rg), —CN;
• each Rc is independently selected from the group consisting of hydrogen, C1-C4 alkyl, and —(CH2)m—Y wherein m is 1, 2 or 3 and Y is selected from the group consisting of —OH, —O(C1-C4-alkyl), —COORe and —CON(Rf)(Rg);
• each Rd is independently selected from the group consisting of optionally substituted aryl, optionally substituted heteroaryl and —(CH2)p—Z wherein p is 1, 2 or 3 and Z is selected from the group consisting of —OH, —O(C1-C4-alkyl), —COORe and —CON(Rf)(Rg);
• and
• each Re, Rf and Rg is independently selected from the group consisting of hydrogen and C1-C4 alkyl.