Hydroxychloroquine Impurity F 是 Hydroxychloroquine 的杂质。Hydroxychloroquine 是一种合成的抗疟疾剂，也可以抑制 Toll 样受体 7/9 (TLR7/9) 信号传导。Hydroxychloroquine 有效抑制 SARS-CoV-2 感染[1][2][3]。

[1]. Manzo C, et al. Psychomotor Agitation Following Treatment with Hydroxychloroquine. Drug Saf Case Rep. 2017 Dec;4(1):6. [2]. Lamphier M, et al. Novel small molecule inhibitors of TLR7 and TLR9: mechanism of action and efficacy in vivo. Mol Pharmacol. 2014 Mar;85(3):429-40. [3]. Yao X, et al. In Vitro Antiviral Activity and Projection of Optimized Dosing Design of Hydroxychloroquine for the Treatment of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2). Clin Infect Dis. 2020 Mar 9. pii: ciaa237.