Correlation between chemotype-dependent binding conformations of HSP90α/ß and isoform selectivity-Implications for the structure-based design of HSP90α/ß selective inhibitors for treating neurodegenerative diseases.

HSP90 continues to be a target of interest for neurodegeneration indications. Selective knockdown of the HSP90 cytosolic isoforms α and ß is sufficient to reduce mutant huntingtin protein levels in vitro. Chemotype-dependent binding conformations of HSP90α/ß appear to strongly influence isoform selectivity. The rational design of HSP90α/ß inhibitors selective versus the mitochondrial (TRAP1) and endoplasmic reticulum (GRP94) isoforms offers a potential mitigating strategy for mechanism-based toxicities. Better tolerated HSP90 inhibitors would be attractive for targeting chronic neurodegenerative diseases such as Huntington's disease.

Novel selective androgen receptor modulators: SAR studies on 6-bisalkylamino-2-quinolinones.

A series of selective androgen receptor modulators (SARMs) with a wide spectrum of receptor modulating activities was developed based on optimization of the 4-substituted 6-bisalkylamino-2-quinolinones (3). Significance of the trifluoromethyl group on the side chains and its interactions with amino acid residues within the androgen receptor (AR) ligand binding domain are discussed. A representative analog (9) was tested orally in a rodent model of hypogonadism and demonstrated desirable tissue selectivity.