Friedelin for COVID-19

 Friedelin has been reported as potentially beneficial for COVID-19 in the following studies.
COVID-19 involves the interplay of 350+ viral and host proteins and factors providing many therapeutic targets. Scientists have proposed 10,000+ potential treatments. c19early.org analyzes 210+ treatments. We have not reviewed Friedelin in detail.
Arumugam et al., In silico evaluation of some commercially available terpenoids as spike glycoprotein of SARS-CoV-2 – inhibitors using molecular dynamic approach, Journal of Biomolecular Structure and Dynamics, doi:10.1080/07391102.2023.2201848
Rena et al., Studi in silico: Screening Virtual Senyawa Triterpenoid pada Canophyllum inophyllum Sebagai Kandidat Inhibitor SARS-CoV-2, Jurnal Fisika Unand, doi:10.25077/jfu.14.5.459-465.2025
Penelitian ini bertujuan untuk mengidentifikasi potensi senyawa-senyawa triterpenoid dari tamanu (Canophyllum inophyllum) sebagai inhibitor SARS-CoV-2 melalui pendekatan in-silico menggunakan molecular docking. Dipilih sepuluh senyawa triterpenoid dan diuji afinitas ikatannya terhadap main protease (Mpro) SARS-CoV-2 (PDB ID:6W63). Hasil menunjukkan bahwa empat senyawa triterpenoid, diantaranya oleanolic acid (-8.2 kcal/mol), friedelin (-8.2 kcal/mol), inophynone (-8.1 kcal/mol), dan epifriedelanol (-8.2 kcal/mol) memiliki binding affinity yang lebih rendah dibandingkan ligand alami (X77 -8.0 kcal/mol) maupun ligand pembandingnya (paxlovid), yang mengindikasikan interaksi yang lebih kuat terhadap situs aktif protein. Diantara empat kandidat, hanya oleanolic acid yang membentuk ikatan hidrogen dengan residu asam amino pada situs aktif protein, yang memperkuat kemungkinan peranannya sebagai inhibitor SARS-CoV-2. Temuan ini menunjukkan bahwa senyawa-senyawa tersebut, khususnya oleanolic acid, berpotensi dikembangkan lebih lanjut sebagai terapi Covid-19 berbasis bahan alam. Studi ini memberikan kontribusi awal dalam ekplorasi bahan alam sebagai sumber senyawa aktif untuk pengembangan terapi Covid-19 melalui pendekatan in-silico
Djouonzo et al., SARS-CoV-2 main protease inhibitors from the stem barks of Discoglypremna caloneura (Pax) Prain (Euphorbiaceae) and Pterocarpus erinaceus Poir (Fabaceae) and their molecular docking investigation, Applied Biological Chemistry, doi:10.1186/s13765-023-00833-y
AbstractThe main viral protease (Mpro) of SARS-CoV-2 provides an excellent target for antivirals, due to its essential and conserved function in the viral replication cycle. We reported in this study, the SARS-CoV-2 main protease inhibitory effect of twelve compounds isolated from D. caloneura and P. erinaceus together with four derivatives. Among the effectively tested samples, two derivatized compounds displayed significant improvement on the activity from the starting material, friedelin (1) through the acetoreduced (2) to the acetoxy product (3) with respective IC50 values of 42.89, 29.69 and 19.39 µg/mL. The latter displayed the highest activity although lower as compared to that of baicalein, the positive control with IC50 0.41 µg/mL. The molecular docking study showed that an increase in the number of hydrogen bonds between compounds and active site of Mpro resulted in increased inhibition. Graphical Abstract
Bizzoca et al., Natural compounds may contribute in preventing SARS-CoV-2 infection: a narrative review, Food Science and Human Wellness, doi:10.1016/j.fshw.2022.04.005
Abou Baker et al., An overview on medicinal plants used for combating coronavirus: Current potentials and challenges, Journal of Agriculture and Food Research, doi:10.1016/j.jafr.2023.100632
Bekheit et al., Potential RNA-dependent RNA polymerase inhibitors as prospective drug candidates for SARS-CoV-2, European Journal of Medicinal Chemistry, doi:10.1016/j.ejmech.2023.115292