Quinoline-based compounds and methods of inhibiting cdk8/19

A compound of Formula 1B

• wherein R1 is —CN, NO2, a halogen, an amino, or a halo-substituted alkyl;
• wherein R3 comprises a substituted or unsubstituted, branched or unbranched C1-C6 alkylene;
• and
• wherein R4 comprises —C(O)NRARB where—
• RA and RB groups on the same nitrogen are taken together with their intervening atoms to form a substituted or unsubstituted 4-7 membered saturated, partially unsaturated, or heteroaryl ring having 0-3 heteroatoms, in addition to the nitrogen, independently selected from nitrogen, oxygen, or sulfur;
• or
• each RA and RB are independently selected from hydrogen, a substituted or unsubstituted alkyl, a substituted or unsubstituted cycloalkyl, a substituted or unsubstituted phenyl, a substituted or unsubstituted 4-7 membered saturated or partially unsaturated heterocyclic having 1-2 heteroatoms independently selected from nitrogen, oxygen, or sulfur, or a substituted or unsubstituted 5-6 membered heteroaryl ring having 1-4 heteroatoms independently selected from nitrogen, oxygen, or sulfur.