Background: Novel coronavirus is a type of enveloped viruses with a single-stranded RNA enclosing helical nucleocapsid. The envelope consists of spikes on the surface which are made up of proteins through which virus enters into human cells. Until now, there is no specific drug or vaccine available to treat COVID-19 infection. In this scenario, reposting of drug or active molecules may provide rapid solution to fight against this deadly disease.

Objective: We selected 30 phytoconstituents from the different plants which are reported for antiviral activities against coronavirus (CoVs) and performed in silico screening to find out phytoconstituents which have potency to inhibit specific target of the novel coronavirus.

Methods: We performed molecular docking studies on three different proteins of novel coronavirus, namely COVID-19 main protease (3CL pro), papain-like protease (PL pro) and spike protein (S) attached to ACE2 binding domain. The screening of the phytoconstituents on the basis of binding affinity compared to standard drugs. The validations of screened compounds were done using ADMET and bioactivity prediction.

Results: We screened five compounds biscoclaurine, norreticuline, amentoflavone, licoricidin and myricetin, using in silico approach. All compounds were found safe in In silico toxicity studies. Bioactivity prediction reveals that these compounds may act through protease or enzyme inhibition. Results of compound biscoclaurine norreticuline were more interesting as this biscoclaurine had higher binding affinity for the target 3CLpro and PLpro targets and norreticuline had a higher binding affinity for the target PLpro and Spike protein.

Conclusion: Our study concludes that these compounds could be further explored rapidly as it may have potential to fight against COVID-19.

背景：新型冠状病毒是一种有包膜病毒，其单链RNA包裹着螺旋状的核衣壳。包膜由表面上的尖刺组成，这些尖刺由病毒进入人体细胞的蛋白质组成。到目前为止，还没有可用于治疗 COVID-19 感染的特定药物或疫苗。在这种情况下，重新发布药物或活性分子可能会为对抗这种致命疾病提供快速解决方案。

目的：我们从不同植物中选择了 30 种具有抗冠状病毒 (CoVs) 抗病毒活性的植物成分，并进行了计算机筛选，以找出能够抑制新型冠状病毒特定靶标的植物成分。

方法：我们对新型冠状病毒的三种不同蛋白质进行分子对接研究，即COVID-19主蛋白酶（3CL pro）、木瓜蛋白酶样蛋白酶（PL pro）和附着于ACE2结合域的刺突蛋白（S）。与标准药物相比，基于结合亲和力筛选植物成分。使用 ADMET 和生物活性预测对筛选的化合物进行验证。

结果：我们采用计算机模拟方法筛选了五种化合物biscoclaurine、norreticuline、amentoflavone、licoricidin和myricetin。在计算机毒性研究中发现所有化合物都是安全的。生物活性预测表明，这些化合物可能通过蛋白酶或酶抑制起作用。复方双可乐林去甲网库林的结果更有趣，因为这种双可乐林对靶标 3CLpro 和 PLpro 靶标具有更高的结合亲和力，而去甲甲氨蝶呤对靶标 PLpro 和 Spike 蛋白具有更高的结合亲和力。

结论：我们的研究得出结论，可以进一步快速探索这些化合物，因为它可能具有对抗 COVID-19 的潜力。