The outbreak of coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has emphasized the urgency to develop effective therapeutics. Drug repurposing screening is regarded as one of the most practical and rapid approaches for the discovery of such therapeutics. The 3C-like protease (3CL^pro), or main protease (M^pro) of SARS-CoV-2 is a valid drug target as it is a specific viral enzyme and plays an essential role in viral replication. We performed a quantitative high-throughput screening (qHTS) of 10 755 compounds consisting of approved and investigational drugs, and bioactive compounds using a SARS-CoV-2 3CL^pro assay. Twenty-three small molecule inhibitors of SARS-CoV-2 3CL^pro have been identified with IC₅₀s ranging from 0.26 to 28.85 μM. Walrycin B (IC₅₀ = 0.26 μM), hydroxocobalamin (IC₅₀ = 3.29 μM), suramin sodium (IC₅₀ = 6.5 μM), Z-DEVD-FMK (IC₅₀ = 6.81 μM), LLL-12 (IC₅₀ = 9.84 μM), and Z-FA-FMK (IC₅₀ = 11.39 μM) are the most potent 3CL^pro inhibitors. The activity of the anti-SARS-CoV-2 viral infection was confirmed in 7 of 23 compounds using a SARS-CoV-2 cytopathic effect assay. The results demonstrated a set of SARS-CoV-2 3CL^pro inhibitors that may have potential for further clinical evaluation as part of drug combination therapies to treating COVID-19 patients and as starting points for chemistry optimization for new drug development.

中文翻译：

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通过定量高通量筛选鉴定 SARS-CoV-2 3CL 蛋白酶抑制剂

由严重急性呼吸综合征冠状病毒 2 (SARS-CoV-2) 引起的 2019 年冠状病毒病 (COVID-19) 的爆发强调了开发有效治疗方法的紧迫性。药物再利用筛选被认为是发现此类疗法的最实用和最快速的方法之一。SARS-CoV-2 的3C 样蛋白酶 (3CL ^pro ) 或主要蛋白酶 (M ^{pro ) 是有效的药物靶点，因为它是一种特定的病毒酶，在病毒复制中发挥重要作用。我们使用 SARS-CoV-2 3CL pro}检测对 10 755 种化合物进行了定量高通量筛选 (qHTS)，这些化合物包括已批准的和在研药物以及生物活性化合物。已鉴定出23 种 SARS-CoV-2 3CL ^{pro小分子抑制剂，其 IC} ₅₀范围为 0.26 至 28.85 μM。Walrycin B (IC ₅₀ = 0.26 μM)、羟钴胺素 (IC ₅₀ = 3.29 μM)、苏拉明钠 (IC ₅₀ = 6.5 μM)、Z-DEVD-FMK (IC ₅₀ = 6.81 μM)、LLL-12 (IC ₅₀ = 9.84) μM) 和 Z-FA-FMK (IC ₅₀ = 11.39 μM) 是最有效的 3CL^前体抑制剂。使用 SARS-CoV-2 细胞病变效应测定，在 23 种化合物中的 7 种中证实了抗 SARS-CoV-2 病毒感染的活性。结果表明，一组 SARS-CoV-2 3CL^前抑制剂可能具有进一步临床评估的潜力，作为治疗 COVID-19 患者的药物组合疗法的一部分，并作为新药开发化学优化的起点。