Benzoheterocyclic analogues of dotinurad as orally efficacious human urate transporter 1 inhibitors: Design, synthesis, structure-activity relationships, and pharmacokinetic studies.

A series of benzoheterocyclic analogues of Dotinurad were designed and synthesized as URAT1 inhibitors via bioisosterism and linker modification strategies. Among the 19 synthesized derivatives, compounds 9, 13, and 14 (bearing benzimidazole, benzotetrahydropyrrole, and benzo[b]thiazine 1,1-dioxide scaffolds, respectively) exhibited acceptable inhibitory potency (IC50: 69.81-441.51 nM), favorable metabolic stability, and improved pharmacokinetic profiles compared to Dotinurad. Notably, despite showing weaker in vitro URAT1 inhibition than the Dotinurad, these three candidates demonstrated significantly superior uricosuric activity in hyperuricemic rats. Mechanistic investigation revealed that the substantial excretion of unchanged prototype compounds into the urine ensured a high local concentration within the renal tubule lumen, which effectively compensated for their moderate in vitro affinity. These findings validated the design strategy and highlighted compounds 9, 13, and 14 as promising candidates for hyperuricemia treatment.