19697-87-1Relevant academic research and scientific papers
Antiviral activities of halogenated emodin derivatives against human coronavirus nl63
Avbelj, Martina,Banjanac, Mihailo,Durán-Alonso, María Beatriz,Horvat, Monika,Iskra, Jernej,Petkovi?, Hrvoje
, (2021/11/27)
The current COVID-19 outbreak has highlighted the need for the development of new vaccines and drugs to combat Severe Acute Respiratory Syndrome-Coronavirus-2 (SARS-CoV-2). Recently, various drugs have been proposed as potentially effective against COVID-19, such as remdesivir, infliximab and imatinib. Natural plants have been used as an alternative source of drugs for thousands of years, and some of them are effective for the treatment of various viral diseases. Emodin (1,3,8-trihydroxy-6-methylanthracene-9,10-dione) is a biologically active anthraquinone with antiviral activity that is found in various plants. We studied the selectivity of electrophilic aromatic substitution reactions on an emodin core (halogenation, nitration and sulfonation), which resulted in a library of emodin derivatives. The main aim of this work was to carry out an initial evaluation of the potential to improve the activity of emodin against human coronavirus NL63 (HCoV-NL63) and also to generate a set of initial SAR guidelines. We have prepared emodin derivatives which displayed significant anti-HCoV-NL63 activity. We observed that halogenation of emodin can improve its antiviral activity. The most active compound in this study was the iodinated emodin analogue E_3I, whose anti-HCoV-NL63 activity was comparable to that of remdesivir. Evaluation of the emodin analogues also revealed some unwanted toxicity to Vero cells. Since new synthetic routes are now available that allow modification of the emodin structure, it is reasonable to expect that analogues with significantly improved anti-HCoV-NL63 activity and lowered toxicity may thus be generated.
Chlorination of anthraquinones by lichen and fungal enzymes
Cohen, Peter A.,Neil Towers
, p. 271 - 274 (2007/10/03)
Chlorination of the anthraquinones, emodin and 7-chloroemodin, was studied with an enzyme preparation from the lichen Nephroma laevigatum, and a commerically available fungal chloroperoxidase (EC 1.11.1.10). The fungal enzyme converted emodin to a mixture of 5-chloro, 7-chloro and 5,7- dichloroemodin, while converting the 7-chloro isomer to 5,7-dichloroemodin in nearly quantitative yield. The lichen enzyme, however, chlorinated emodin only at C-7 and failed to chlorinate 7-chloroemodin further. In non-enzymic controls, emodin gave the same set of products as the fungal enzyme but 7- chloroemodin did not undergo further chlorination. The chemical structures of the products were confirmed from UV, El-mass and 1H NMR spectral data.
