AbstractTick‐borne encephalitis virus (TBEV), yellow fever virus (YFV), and West Nile virus (WNV) are flaviviruses causing emerging arthropod‐borne infections of a great public health concern. Clinically approved drugs are not available to complement or replace the existing vaccines, which do not provide sufficient coverage. Thus, the discovery and characterization of new antiflaviviral chemotypes would advance studies in this field. In this study, a series of tetrahydroquinazoline N‐oxides was synthesized, and the antiviral activity of the compounds was assessed against TBEV, YFV, and WNV using the plaque reduction assay along with the cytotoxicity to the corresponding cell lines (porcine embryo kidney and Vero). Most of the studied compounds were active against TBEV (EC50 2 to 33 μM) and WNV (EC50 0.15 to 34 μM) and a few also demonstrated inhibitory activity against YFV (EC50 0.18 to 41 μM). To investigate the potential mechanism of action of the synthesized compounds, time‐of‐addition (TOA) experiments and virus yield reduction assays were performed for TBEV. The TOA studies suggested that the antiviral activity of the compounds should affect the early stages of the viral replication cycle after cell entry. Compounds with tetrahydroquinazoline N‐oxide scaffold show a broad spectrum of activity against flaviviruses and represent a promising chemotype for antiviral drug discovery.
摘要蜱传脑炎病毒(TBEV)、黄热病病毒(YFV)和西尼罗河病毒(WNV)是引起新出现的节肢动物传播感染的黄病毒,是公共卫生的重大问题。目前还没有临床认可的药物来补充或替代现有的疫苗,因为现有疫苗的覆盖范围不够。因此,发现和鉴定新的抗黄病毒
化学型将推动这一领域的研究。本研究合成了一系列四氢
喹唑啉 N-氧化物,并使用斑块还原试验评估了这些化合物对 TBEV、YFV 和 WNV 的抗病毒活性以及对相应
细胞系(猪胚肾和 Vero)的细胞毒性。所研究的大多数化合物对 TBEV(
EC50 2 至 33 μM)和 WNV(
EC50 0.15 至 34 μM)具有活性,少数化合物还对 YFV(
EC50 0.18 至 41 μM)具有抑制活性。为了研究合成化合物的潜在作用机制,研究人员对 TBEV 进行了添加时间(
TOA)实验和病毒产量降低实验。
TOA 研究表明,这些化合物的抗病毒活性应该会影响进入细胞后病毒复制周期的早期阶段。具有四氢
喹唑啉 N-氧化物支架的化合物对黄病毒具有广谱的抗病毒活性,是抗病毒药物发现中一种很有前途的
化学类型。