Myst family histone acetyltransferase inhibitors

A compound of formula I′:

• or a pharmaceutically acceptable salt thereof, wherein:
• Z is selected from —Cy, —(C1-3 aliphatic)-Cy, or optionally substituted C1-4 aliphatic;
• Cy is an optionally substituted group selected from phenyl, a 3-10 membered saturated or partially unsaturated carbocyclic ring, a 6-10 membered bridged bicyclic carbocyclic ring, a 3-10 membered saturated or partially unsaturated heterocyclic ring having 1-2 heteroatoms independently selected from nitrogen, oxygen and sulfur, a 6-8 membered bridged bicyclic heterocyclic ring having 1-2 heteroatoms independently selected from nitrogen, oxygen and sulfur, a 5-6 membered heteroaryl ring having 1-3 heteroatoms independently selected from nitrogen, oxygen and sulfur, an 8-10 membered bicyclic aryl ring, and an 8-10 membered bicyclic heteroaryl ring having 1-3 heteroatoms independently selected from nitrogen oxygen and sulfur;
• each of R1 and R2 is independently selected from halogen and C1-4 aliphatic;
• R3 is selected from hydrogen, halogen, —CN, —NR2, and optionally substituted C1-4 aliphatic;
• each R is independently selected from hydrogen, optionally substituted C1-4 aliphatic, and —C(O)O(C1-4 aliphatic);
• Ring A is an optionally substituted 5- or 6-membered heteroaryl ring having 1-4 heteroatoms independently selected from nitrogen, oxygen and sulfur;
• each Ra is selected from halogen and optionally substituted C1-4 aliphatic;
• and
• x is 0-3;
• provided that the compound is not