ACE2 and COVID-19: Artemisin (45) and a limonoid, 6-α-acetoxygedunin (46), as well as glycyrrhizin (47) are terpenoids which showed potential inhibition against the COVID-19 main protease active site and ACE2 in an in silico study (Chen and Du, 2020; Khandelwal and Sharma, 2020; Omaret al., 2020) Also, among the several natural products screened by docking analysis, glycyrrhizin (47) and some other natural products including tryptanthrine, rhein and berberine were found to exhibit a higher degree of interaction with the COVID-19 main protease (Narkhede et al., 2020).