As the most abundant heat shock protein (HSP), Hsp90 is actively involved in tumor cell growth and various responses to anti-carcinogenic stress. Hsp90 has thus emerged as a potential drug target. A structure-based drug design approach was applied to develop novel resorcinolyltriazole derivatives as Hsp90 inhibitors. Structure-activity relationships (SARs) and molecular docking were investigated to provide a rationale for binding affinity and paralog selectivity. Click chemistry between iodoethynylresorcinol and an azido derivative was used to synthesize a new family of 2-((4-resorcinolyl)-5-aryl-1,2,3-triazol-1-yl) acetates that exhibited Hsp90 binding affinities of 40-100 nM (IC50). Among the synthesized molecules, the triazole alkyl acetates displayed the highest Hsp90 binding affinities. Their potency against Hsp90 was over 100-fold stronger than against TRAP1 and 1-3-fold stronger than against Grp94. In particular, compounds 18, 19, and 30 had Hsp90 inhibitory activities of ~45 nM (IC50) and they displayed over 350-fold selectivity for Hsp90 over TRAP1.
Keywords: Grp94; Hsp90; Inhibitor; Resorcinol; Selectivity; TRAP1; Triazole.
Copyright © 2019 Elsevier Ltd. All rights reserved.