Compounds, compositions, and methods for protein degradation

A compound of Formula I:

• or a pharmaceutically acceptable salt or stereoisomer thereof, wherein
• A is
• E is
• X1 and X2 are each independently selected from O, NR3, and S;
• or X1 or X2 combine with L to form a heterocyclyl or heteroaryl;
• or both of X1 and X2 combine with L to form a heterocyclyl or heteroaryl;
• L comprises an alkylene, cycloalkylene, heterocyclylene, arylene, or heteroarylene chain, or a combination thereof, comprising 1 to 35 carbon atoms, optionally wherein:
• if L comprises an alkylene comprising 1 to 35 —CH2— moieties, then at least one, but no more than ten, —CH2— moieties of L are independently replaced with a moiety selected from —C(═O)—, —C(═O)—NR4—, —NR4—C(═O)—, —C(═O)—O—, —O—C(═O)—, —NR4—C(═O)—NR3—, —O—C(═O)—NR4—, —NR4—C(═O)—O—, —O—, —S—, and —NR4—, provided that the number of —CH2— moieties of L is larger than the collective number of —C(═O)—, —C(═O)—NR4—, —NR4—C(═O)—, —C(═O)—O—, —O—C(═O)—, —NR4—C(═O)—NR3—, —O—C(═O)—NR4—, —NR4—C(═O)—O—, —O—, —S—, and —NR3— moieties of L, and provided there is at least one —CH2— between each —C(═O)—, —C(═O)—NR4—, —NR4—C(═O)—, —C(═O)—O—, —O—C(═O)—, —NR4—C(═O)—NR3—, —O—C(═O)—NR4—, —NR4—C(═O)—O—, —O—, —S—, and —NR4— moiety of L;
• R1 is halo;
• R2 is H;
• R3 and R4 are each independently selected from H and alkyl;
• and
• n is 1-5.