Alpha-cinnamide compounds and compositions as hdac8 inhibitors

A compound of Formula (Ia):

• or a pharmaceutically acceptable salt thereof,
• wherein
• A is hydrogen;
• het is a 3-to-12 membered heterocycle, wherein said heterocycle is optionally substituted with one or more Rd;
• each Rd is independently hydrogen, hydroxyl, C1-C6 alkyl, C1-C6 haloalkyl, C1-C6 alkoxy, cyano, oxo, C3-C8 cycloalkyl, 3-to-12 membered heterocycloalkyl, aryl, heteroaryl, —(CH2)nRe, —(CH2)nO(CH2)mRe, —(CH2)nNReRf, —C(O)(CH2)nRe, —(CH2)nC(O)ORe, —C(O)(CH2)nSRe, —(CH2)nC(O)NReRf, —NH(CH2)nRe, —NHC(O)(CH2)nRe, —NHC(O)(CH2)ORe, —NHC(O)(CH2)nSRe, —NHS(O)2Re, —ORe, or —S(O)2Re, wherein each alkyl, haloalkyl, alkoxy, cycloalkyl, heterocycloalkyl, aryl, or heteroaryl is optionally substituted with one or more Re or Rf;
• or two Rd when attached to the same carbon atom can form a C5-C12spirocycle or a 3- to 12-membered spiroheterocycle, wherein the spirocycle or the spiroheterocycle are optionally substituted with one or more Re or Rf;
• each Re is independently hydrogen, hydroxyl, C1-C6 alkyl, C1-C6 alkyl, C1-C6 alkoxy, C3-C8 cycloalkyl, heterocycloalkyl, aryl, heteroaryl, —C(O)(CH2)nRf, or —(CH2)nC(O)Rf, wherein each alkyl, alkoxy, cycloalkyl, heterocycloalkyl, aryl, or heteroaryl is optionally substituted with one or more Rf;
• each Rf is independently hydrogen, C1-C6 alkyl, C1-C6 haloalkyl, C1-C6 alkoxy, C1-C6 haloalkoxy, cyano, oxo, cycloalkyl, 3-to-12 membered heterocycloalkyl, aryl, heteroaryl, (C1-C6)alkylaryl, halogen, —(CH2)nO(CH2)mCH3, —(CH2)nN(CH3)2, —(CH2)nO(CH2)mN(CH3)2, —(CH2)nNReRf, —N(CH3)S(O)2CH3, —S(CH2)mCH3, or —S(O)2(CH2)mCH3, wherein each alkyl, haloalkyl, alkoxy, haloalkoxy, cycloalkyl, heterocycloalkyl, aryl, or heteroaryl is optionally substituted with one or more alkyl, haloalkyl, alkoxy, haloalkoxy, cyano, oxo, halogen, cycloalkyl, heterocycloalkyl, aryl, or heteroaryl;
• n is 0, 1, 2, 3, or 4;
• and
• m is 0, 1, 2, 3, or 4.