Syntheses of Potent, Selective, and Orally Bioavailable Indazole-Pyridine Series of Protein Kinase B/Akt Inhibitors with Reduced Hypotension.
Zhu, G.D., Gandhi, V.B., Gong, J., Thomas, S., Woods, K.W., Song, X., Li, T., Diebold, R.B., Luo, Y., Liu, X., Guan, R., Klinghofer, V., Johnson, E.F., Bouska, J., Olson, A., Marsh, K.C., Stoll, V.S., Mamo, M., Polakowski, J., Campbell, T.J., Martin, R.L., Gintant, G.A., Penning, T.D., Li, Q., Rosenberg, S.H., Giranda, V.L.(2007) J Med Chem 50: 2990
- PubMed: 17523610 
- DOI: https://doi.org/10.1021/jm0701019
- Primary Citation of Related Structures:  
2UZT, 2UZU, 2UZV, 2UZW - PubMed Abstract: 
Compound 7 was identified as a potent (IC50 = 14 nM), selective, and orally bioavailable (F = 70% in mouse) inhibitor of protein kinase B/Akt. While promising efficacy was observed in vivo, this compound showed effects on depolarization of Purkinje fibers in an in vitro assay and CV hypotension in vivo. Guided by an X-ray structure of 7 bound to protein kinase A, which has 80% homology with Akt in the kinase domain, our efforts have focused on structure-activity relationship (SAR) studies of the phenyl moiety, in an attempt to address the cardiovascular liability and further improve the Akt potency. A novel and efficient synthetic route toward diversely substituted phenyl derivatives of 7 was developed utilizing a copper-mediated aziridine ring-opening reaction as the key step. To improve the selectivity of these Akt inhibitors over other protein kinases, a nitrogen atom was incorporated into selected phenyl analogues of 7 at the C-6 position of the methyl indazole scaffold. These modifications resulted in the discovery of inhibitor 37c with greater potency (IC50 = 0.6 nM vs Akt), selectivity, and improved cardiovascular safety profile. The SARs, pharmacokinetic profile, and CV safety of selected Akt inhibitors will be discussed.
Organizational Affiliation: 
Cancer Research, Preclinical Safety, Structural Biology, Integrative Pharmacology, GPRD, Abbott Laboratories, 100 Abbott Park Road, Abbott Park, Illinois 60064-6101, USA. gui-dong.zhu@abbott.com