Emodin

Emodin (6-methyl-1,3,8-trihydroxyanthraquinone) is a chemical compound, of the anthraquinone family, that can be isolated from rhubarb, buckthorn, and Japanese knotweed (Reynoutria japonica syn. Polygonum cuspidatum). Emodin is particularly abundant in the roots of the Chinese rhubarb (Rheum palmatum), knotweed and knotgrass (Polygonum cuspidatum and Polygonum multiflorum) as well as Hawaii ‘au‘auko‘i cassia seeds or coffee weed (Semen cassia). It is specifically isolated from Rheum palmatum L. It is also produced by many species of fungi, including members of the genera Aspergillus, Pyrenochaeta, and Pestalotiopsis, inter alia. The common name is derived from Rheum emodi, a taxonomic synonym of Rheum australe, (Himalayan rhubarb) and synonyms include emodol, frangula emodin, rheum emodin, 3-methyl-1,6,8-trihydroxyanthraquinone, Schüttgelb (Schuttgelb), and Persian Berry Lake.

Emodin

Names
Preferred IUPAC name 1,3,8-Trihydroxy-6-methylanthracene-9,10-dione
Other names 6-Methyl-1,3,8-trihydroxyanthraquinone
Identifiers
CAS Number	518-82-1 Y
3D model (JSmol)	Interactive image
ChEBI	CHEBI:42223 Y
ChEMBL	ChEMBL289277 Y
ChemSpider	3107 Y
DrugBank	DB07715 Y
ECHA InfoCard	100.007.509
KEGG	C10343 Y
PubChem CID	3220
UNII	KA46RNI6HN Y
CompTox Dashboard (EPA)	DTXSID5025231
InChI InChI=1S/C15H10O5/c1-6-2-8-12(10(17)3-6)15(20)13-9(14(8)19)4-7(16)5-11(13)18/h2-5,16-18H,1H3 Y Key: RHMXXJGYXNZAPX-UHFFFAOYSA-N Y InChI=1/C15H10O5/c1-6-2-8-12(10(17)3-6)15(20)13-9(14(8)19)4-7(16)5-11(13)18/h2-5,16-18H,1H3 Key: RHMXXJGYXNZAPX-UHFFFAOYAD
SMILES O=C2c1cc(cc(O)c1C(=O)c3c2cc(O)cc3O)C
Properties
Chemical formula	C15H10O5
Molar mass	270.240 g·mol−1
Appearance	Orange solid
Density	1.583±0.06 g/cm3
Melting point	256 to 257 °C (493 to 495 °F; 529 to 530 K)
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). Y verify (what is YN ?) Infobox references

Emodin is an active component of several plants used in traditional Chinese medicine (TCM) such as Rheum palmatum, Polygonum cuspidatum, and Polygonum multiflorum. It has various actions including laxative, antibacterial and antiinflammatory effects, and has also been identified as having potential antiviral activity against coronaviruses such as SARS-CoV-2, being one of the major active components of the antiviral TCM formulation Lianhua Qingwen.

A computational study was conducted to investigate the inhibition mechanism on the formation of the Spike-ACE2 protein complex. Specifically, it is seen dose-dependent inhibition in the prevention of infection by SARS-CoV-1, evidence which has stimulated further investigations on SARS-CoV-2.

Emodin has been shown to inhibit the ion channel of protein 3a, which could play a crucial role in the release of the virus from infected cells.

The following plant species produce emodin:

• Acalypha australis
• Cassia occidentalis
• Cassia siamea
• Frangula alnus
• Glossostemon bruguieri
• Kalimeris indica
• Polygonum hypoleucum
• Reynoutria japonica (syn. Fallopia japonica) (syn. Polygonum cuspidatum)
• Rhamnus alnifolia, the alderleaf buckthorn
• Rhamnus cathartica, the common buckthorn
• Rheum palmatum
• Rumex nepalensis
• Senna obtusifolia (syn. Cassia obtusifolia)
• Thielavia subthermophila
• Ventilago madraspatana

Emodin also occurs in variable amounts in members of the crustose lichen genus Catenarina.

• British Pharmacopoeia

• List of compounds with carbon number 15