HSP90 N-TERMINAL DOMAIN with pochoxime B
[HS90A_HUMAN] Molecular chaperone that promotes the maturation, structural maintenance and proper regulation of specific target proteins involved for instance in cell cycle control and signal transduction. Undergoes a functional cycle that is linked to its ATPase activity. This cycle probably induces conformational changes in the client proteins, thereby causing their activation. Interacts dynamically with various co-chaperones that modulate its substrate recognition, ATPase cycle and chaperone function. 
Publication Abstract from PubMed
The pochoximes, based on the radicicol pharmacophore, are potent inhibitors of heat shock protein 90 (HSP90) that retain their activity in vivo. Herein we report an extended library that broadly explores the structure-activity relationship (SAR) of the pochoximes with four points of diversity. Several modifications were identified that afford improved cellular efficacy, new opportunities for conjugation, and further diversifications. Cocrystal structures of pochoximes A and B with HSP90 show that pochoximes bind to a different conformation of HSP90 than radicicol and provide a rationale for the enhanced affinity of the pochoximes relative to radicicol and the pochonins.
Inhibition of HSP90 with pochoximes: SAR and structure-based insights.,Barluenga S, Fontaine JG, Wang C, Aouadi K, Chen R, Beebe K, Neckers L, Winssinger N Chembiochem. 2009 Nov 23;10(17):2753-9. PMID:19856365
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.