Immunoproteasome inhibitors

A compound of Formula (I):

• and/or a pharmaceutically acceptable salt thereof, wherein:
• W is —O—P-Q-C(R8a)═C(R8b)(R8c) or a group of formula
• A1 is hydrogen, hydroxy, optionally substituted alkyl, optionally substituted aryl, optionally substituted heteroaryl, optionally substituted heterocyclyl, or —S(═O)2-alkyl, wherein said alkyl of said —S(═O)2-alkyl is optionally substituted;
• P is -alkyl-N(R)—, -alkyl-(C3-C6)cycloalkyl-N(R)—, -alkyl-O-alkyl-N(R)—,
• Z and Z1 are independently a covalent bond, -alkyl-, -alkyl-O—, -alkyl-N(R)—, or -alkyl-O-alkyl-, with the proviso that Z is connected to ring A at a carbon atom adjacent to the ring nitrogen atom;
• ring A with the ring nitrogen atom shown is an optionally substituted saturated mono- or multicyclic 4 to 10 membered heterocyclyl;
• ring J with the ring nitrogen atom and ring Y1 atom shown is a saturated 4 to 10 membered heterocyclyl;
• Y1 is C or N;
• Z2 is a covalent bond or N(R), with the proviso that when Y1 in ring J is nitrogen, then Z2 is a covalent bond;
• each R is independently hydrogen, or alkyl;
• Q is —C(═O)— or —S(═O)2—;
• R8a is hydrogen, halogen, or cyano;
• R8b is hydrogen, optionally substituted alkyl, optionally substituted cycloalkyl, optionally substituted heteroaryl, or optionally substituted heterocyclyl;
• or
• R8a and R8b are taken together to form a bond;
• and
• R8c is hydrogen or optionally substituted alkyl;
• Rb1 is optionally substituted alkyl, optionally substituted aryl, optionally substituted heteroaryl, optionally substituted cycloalkyl, or optionally substituted heterocyclyl;
• and
• Rb2 and Rb3 are independently hydrogen or optionally substituted alkyl;
• or
• Rb2 and Rb3 together with the boron atom to which they are shown attached form a cyclic boronic ester.