C-terminal HSP90 inhibitors

A pharmaceutical composition comprising a compound of Formula I:

• wherein
• R1 is hydrogen, hydroxy, halo, trifluoroalkyl, alkyl, alkenyl, alkynyl, carbocyclic, heterocyclic, aryl, aralkyl, carboxyl, amido, amino, alkoxy, sulfanyl, sulfenyl, sulfonyl, or ether;
• R2 is hydrogen, halo, hydroxy, trifluoromethyl, alkoxy, alkyl, alkenyl, alkynyl, carbocyclic, alkylcarbocyclic, alkylheterocyclic, heterocyclic, or —R9—OR10, wherein R9 is a covalent bond or alkyl, and R10 is hydrogen, alkyl, C-amido or acyl;
• R3 is hydrogen, hydroxy, halo, trifluoroalkyl, alkyl, alkoxy, sulfanyl, or —R11—O—R12, wherein R11 is a covalent bond or alkyl, and R12 is alkyl, C-amido, or acyl;
• R4 is hydrogen or alkyl;
• R5 is hydrogen or alkyl;
• R6 is hydrogen, hydroxy, sulfanyl, alkyl, or alkoxy;
• R7 is hydrogen or hydroxyl;
• R8 is hydrogen or hydroxyl;
• X1 is —CHR19—, and wherein R19 is selected from hydrogen, halo, alkyl, alkenyl, and alkynyl;
• X2 is —CHR20—, and wherein R20 is selected from hydrogen, halo, alkyl, alkenyl, and alkynyl;
• X is ═CR21— or ═N—, wherein R21 is hydrogen, halo, trifluoromethyl, alkyl, alkenyl, alkynyl, alkoxy, or hydroxy;
• R′ is hydrogen or alkyl;
• R″ is alkyl;
• Y is ═CR3— or ═N—;
• Z is CH or Z-Z1 is —C═C—;
• Z1 is CH or Z-Z1 is —C═C—;
• and
• n is 0, 1, 2, or 3
• and a pharmaceutically acceptable carrier.