Efficacy of top analogs in cochlear explants treated with cisplatin. (A) Outer hair-cell counts for cochlear explants treated with medium alone, cisplatin alone, cisplatin + analog 4, cisplatin + analog 5, cisplatin + analog 7, or cisplatin + analog 14. All compounds were tested at a concentration of 150 nM. OHC counts for media alone were considered as complete protection from cisplatin-induced toxicity and OHC counts for cisplatin alone were considered as no protection. Number of explants tested indicated within each bar. Cell counts for explants treated with cisplatin + analog 7 (150 nM) were significantly different from explants treated with cisplatin alone (*P < 0.05). (B) The chemical structure of analog 7 and its EC50 in cochlear explants treated with cisplatin. (C) The dose response of analog 7 in P3 cochlear explants from mice.