Article
Author: Illuzzi, Giuditta ; Pei, Xiaohui ; Pike, Andy ; Gunnarsson, Anders ; Degorce, Sébastien L. ; Hande, Sudhir M. ; Talbot, Verity ; Zhang, Andrew X. ; Johannes, Jeffrey W. ; Fawell, Stephen ; Yao, Tieguang ; Balazs, Amber Y. S. ; Liu, Lina ; Packer, Martin J. ; Critchlow, Susan E. ; Xue, Lin ; Orme, Jonathan P. ; Larner, Carrie J.B. ; Barratt, Derek ; Staniszewska, Anna D. ; Bista, Michal ; Lane, Jordan ; Pachl, Fiona ; Di Fruscia, Paolo ; Zheng, Xiaolan ; Madin, Andrew ; Schimpl, Marianne ; McWilliams, Lisa ; Leo, Elisabetta ; Hemsley, Paul ; Chuba, Matthew D. ; Underwood, Elizabeth ; Gill, Sonja J. ; Edmondson, Scott D. ; Embrey, Kevin J. ; Heightman, Tom D. ; Varnes, Jeffrey G. ; She, Hongyao ; Ghosh, Avipsa ; Cosulich, Sabina ; O’Connor, Mark J. ; Zhang, Ke
PARP inhibitors have attracted considerable interest in drug discovery due to the clinical success of first-generation agents such as olaparib, niraparib, rucaparib, and talazoparib. Their success lies in their ability to trap PARP to DNA; however, first-generation PARP inhibitors were not strictly optimized for trapping nor for selectivity among the PARP enzyme family. Previously we described the discovery of the second-generation PARP inhibitor AZD5305, a selective PARP1-DNA trapper. AZD5305 maintained the antitumor efficacy of first-generation PARP inhibitors while exhibiting lower hematological toxicity. Recently, there has been interest in central nervous system (CNS)-penetrant PARP inhibitors for CNS malignancies and other neurological conditions; however, AZD5305 is not CNS penetrant. Herein we describe the discovery and optimization of a series of CNS-penetrant, PARP1-selective inhibitors and PARP1-DNA trappers, culminating in the discovery of AZD9574, a compound that maintains the PARP1 selectivity of AZD5305 with improved permeability, reduced efflux, and increased CNS penetration.