Patent ID: 6849713

Claim:
A compound of Formula (I): wherein; Z 1 and Z 2 are independently —NR 3 — or —O—; R 1 and R 2 are independently substituted alkyl, substituted aryl, heteroaryl, or substituted heteroaryl provided that at least one of R 1 and R 2 is a group that can form a pharmaceutically acceptable acid addition salt; R 3 is hydrogen, alkyl or R 3 and R 1 or R 2 together with the atoms to which they are attached form a heterocyclic ring; X 2 is a fused bicyclic or tricyclic heteroaryl group: X 2 and X 3 are independently aryl, substituted aryl, heteroaryl, substituted heteroaryl, or —CHR 4 , wherein R 4 is natural or unnatural amino acid side chain; or a pharmaceutically acceptable acid addition salt thereof.