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Due to alarming outbreak of pandemic COVID‐19 in recent times, there is a strong need to discover and identify new antiviral agents acting against SARS CoV‐2. Among natural products, lignan derivatives have been found effective against several viral strains including SARS CoV‐2. Total of twenty‐seven reported antiviral lignan derivatives of plant origin have been selected for computational studies to identify the potent inhibitors of SARS CoV‐2. Molecular docking study has been carried out in order to predict and describe molecular interaction between active site of enzyme and lignan derivatives. Out of identified hits, clemastatin B and erythro‐strebluslignanol G demonstrated stronger binding and high affinity with all selected proteins. Molecular dynamics simulation studies of clemastin B and savinin against promising targets of SARS CoV‐2 have revealed their inhibitory potential against SARS CoV‐2. In fine, in‐silico computational studies have provided initial breakthrough in design and discovery of potential SARS CoV‐2 inhibitors.

Background: Aspartic protease found in plasmodium parasites such as plasmepsin I, II and IV plays an important role in the degradation of hemoglobin. The studies have shown that effective drug must be able to inhibit more than one type of plasmepsin to avoid further growth of parasites and to prevent resistance of drug. Therefore, plasmepsins are believed to be excellent drug target for malarial disease. Extract of the plant Euphorbia hirta has been proved to exert antimalarial activity. However, molecular mechanism of this activity was not described. Aim: The aim of present investigation is to identify antimalarial phytochemicals of Euphorbia hirta as plasmepsin protease inhibitors using an in silico approach. Materials and methods: Docking studies were performed on three different protein targets plasmepsin I, II, and IV using iGEMDOCK. ADME and bioactivity predictions were done using molinspiration online tool. Toxicity studies were performed using ProTox-II online tool. Results: In the docking studies seven compounds showed significant inhibitory activity with low docking score as compared to standard drug artemisinin. Six compounds showed no violations as per Lipinski rule. Bioactivity prediction states that all the compounds may act through enzyme inhibition. The results of in silico studies suggest that out of the eleven selected phytochemicals isorhamnetin and pinocembrin have more drug likeliness properties and lesser in silico toxicity with more binding affinity than artemisinin on all receptors.  Conclusion: These findings indicate that isorhamnetin and pinocembrin have promising potential for development of antimalarial drug as plasmepsin inhibitors.

The DNA repair process protects the cells from DNA damaging agent by multiple pathways. Majority of the cancer therapy cause DNA damage which leads to apoptosis. The cell has natural ability to repair this damage which ultimately leads to development of resistance of drugs. The key enzymes involved in DNA repair process are poly(ADP-ribose) (PAR) and poly(ADP-ribose) polymerases (PARP). Tumor cells repair their defective gene via defective homologues recombination (HR) in the presence of enzyme PARP. PARP inhibitors inhibit the enzyme poly(ADP-ribose) polymerases (PARPs) which lead to apoptosis of cancer cells. Current clinical data shows the role of PARP inhibitors is not restricted to BRCA mutations but also effective in HR dysfunctions related tumors. Therefore, investigation in this area could be very helpful for future therapy of cancer. This review gives detail information on the role of PARP in DNA damage repair, the role of PARP inhibitors and chemistry of currently available PARP inhibitors.

Background: Novel Corona virus 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 had selected 30 phytoconstituents from the different plants which are reported for antiviral activities against corona virus (CoVs) and performed insilico screening to find out phytoconstituents which have potency to inhibit specific target of novel corona virus. Methods: We had perform molecular docking studies on three different proteins of novel corona virus 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 had screened five compounds biscoclaurine, norreticuline, amentoflavone, licoricidin and myricetin using insilico approach. All compounds found safe in insilico toxicity studies. Bioactivity prediction reviles that these all 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 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.