478-43-3 Usage
Physical and Chemical Properties
The chemical name of Rhein is 1,8-dihydroxy anthraquinone-3-carboxylic acid, with the molecular formula C15H8O6 and the molecular weight of 284.21. It becomes yellow acicular crystal after sublimation, with the melting point 321~322 ℃ and decomposition temperature 330 ℃ and UVλmax (methanol) 229, 258, 435nm. It is soluble in alkali and pyridine, and slightly soluble in alcohol, ether, benzene, chloroform, petroleum ether, and insoluble in water. It can form red sylvine and pink sodium salt, and form a red precipitate with calcium hydroxide and barium hydroxide.
Production Method: being acquired from the hydrolysis of Rhein diacetic ester.
diethyl acetate. Uses: Current clinical treatment of rheumatic drugs often contain Rhein.
Rhein is extracted from the root of the plant Rheum palmatum L. in Polygonaceae family, which is a anthraquinones and has the functions of antibacterial, anti-cancer, cathartic, and diuretic. The contents of rhein, aloe-emodin and rheum emodin in rhubarb are listed in the following table:
Table 1. The contents of rhein, aloe-emodin and rheum emodin in rhubarb (n=2%).
Pharmacological effects
There are chemical compounds chrysophanic acid, rhein, aloe-emodin, rheum emodin, aloe emodin, and Sennoside in rhubarb.
Both the rhein and rheum emodin have the anti-tumor effect, especially a strong inhibitory effect for melanoma and they have certain inhibition on breast cancer and ehrlich’s ascites carcinoma. When rhein was applied to intratumoral administration in mice with breast cancer, there was a significant damaging in the cancer tissue. The inhibition rate of 5mg/kg rhein and rheum emodin on murine melanoma was 76% and 73%, respectively. Rheum emodin has significant competitive inhibition on tyrosinase, and this inhibition may be one of the mechanisms why rhubarb has the anti-melanoma effect. At the concentration of 10μg/ml, Rheum emodin significantly inhibited the cell division and DNA biosynthesis of human lung cancer A-549 cells. After the subcutaneous injection of crude extracts of rhubarb, an inhibition of mouse sarcoma S37 was found. The inhibition rate of Rhein on ehrlich’s ascites carcinoma and sarcoma S180 in mice was 15% and 21%, respectively. The inhibition rate of hot water extracts of Rhubarb on sarcoma S180 in mice was 48.8%.
Rhein has inhibition effect on mouse leukemia P388. Rhein, aloe-emodin and rheum emodin are extracted from rhubarb and these three anthraquinone derivatives could minimize the amount of ascites and the number of cancer cells in different extent in mice with tumors, among which the effect of rhein was most obvious and the effect of aloe-emodin was poorer, with a almost parallel relationship with prolonged survival time. The inhibition of rhein and rheum emodin on biosynthesis of DNA, RNA and protein was stronger, whereas the inhibition of aloe-emodin was weaker.
Uses
Different sources of media describe the Uses of 478-43-3 differently. You can refer to the following data:
1. Medical intermediate;raw materials of health food.
2. Rhein is used to inhibit growth factor beta-1 induced plasminogen activator inhibitor-1 in endothelial cells. It acts as an antibacterial agent against Staphylococcus aureus. It is also used as a laxative. Further, it is employed as a pharmaceutical intermediate.
3. Rhein was used to induce necrosis-apoptosis switch in injured pancreatic acinar cells.
General Description
Yellow needles (from methanol) or yellow-brown powder.
Air & Water Reactions
Insoluble in water.
Reactivity Profile
Rhein forms a red potassium salt and a pink sodium salt.
Hazard
Low toxicity by ingestion.
Fire Hazard
Flash point data for Rhein are not available; however, Rhein is probably combustible.
Biochem/physiol Actions
Constituent that is enriched in rhubarb with anti-inflammatory, anti-osteoarthritic, and anti-cancer activity. It reduces IL-1β production and secretion, caspase-3 activity, inducible nitric oxide synthase activity, and phosphorylation of c-Jun and c-Jun NH2-terminal kinase (JNK).
Safety Profile
A poison by intravenous route. Low toxicity by ingestion. When heated to decomposition it emits acrid smoke and irritating vapors.
Check Digit Verification of cas no
The CAS Registry Mumber 478-43-3 includes 6 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 3 digits, 4,7 and 8 respectively; the second part has 2 digits, 4 and 3 respectively.
Calculate Digit Verification of CAS Registry Number 478-43:
(5*4)+(4*7)+(3*8)+(2*4)+(1*3)=83
83 % 10 = 3
So 478-43-3 is a valid CAS Registry Number.
InChI:InChI=1/C15H8O6/c16-9-3-1-2-7-11(9)14(19)12-8(13(7)18)4-6(15(20)21)5-10(12)17/h1-5,16-17H,(H,20,21)/p-1
478-43-3Relevant articles and documents
Synthesis and pharmacokinetic profile of rhein- boswellic acid conjugate
Suneela, Dhaneshwar,Dipmala, Patil
, p. 7582 - 7587 (2012)
Rhein, an active metabolite of diacerein, down-regulates the gene-expression and production of pro-matrix metalloproteinases and up-regulates the tissue inhibitors of metalloproteinase-1 production. The therapeutic effects of diacerein on osteoarthritis are, at least in part, due to the chondroprotective effect of rhein. Boswellic acid is a specific, non-redox inhibitor of leukotriene synthesis. It is claimed to possess good anti-inflammatory, anti-arthritic, analgesic, and anti-ulcer activities. It prevents the destruction of articular cartilage by decreasing degradation of glycosaminoglycans. Therefore, rhein and boswellic acid were linked chemically through a bioreversible ester linkage to synthesize their mutual prodrug by reported procedure. In vitro release profile of this prodrug was extensively studied in aqueous buffers of varied pH, upper GIT homogenates and 80% human plasma. In vivo release studies were undertaken in blood, urine and feces of rats. The prodrug was stable in HCl buffer (pH 1.2) and stomach homogenates of rats. However; in phosphate buffer (pH 7.4) and in intestinal homogenates the prodrug exhibited 91% and 96% release of rhein and 27.5% and 38% release of boswellic acid respectively over a period of 6 h following first order kinetics. In 80% human plasma (in vitro) and rat blood (in vivo) also 96.35% and 91% release of rhein and 78% and 86.41% release of boswellic acid respectively was observed. The 24 h pooled samples of rat urine revealed presence of 6.2% intact prodrug, 7.1% of rhein and 8.9% of boswellic acid indicating their renal excretion. Samples of rat feces pooled over a period of 24 h showed absence of rhein and presence of 3.1% of intact boswellic acid and 4.6% of boswellic acid emphasizing their intestinal excretion. The in vivo release kinetics of prodrug in rat clearly indicated activation of prodrug to be occurring in blood, being catalyzed by the weak alkaline pH of blood (7.4) in combination with esterases present therein.
Oesterle,Riat
, p. 527 (1909)
Synthesis of rhein and diacerein: a chemoenzymatic approach using anthrol reductase of Talaromyces islandicus
Rajput, Anshul,Mondal, Amit,Pandey, Satyendra Kumar,Husain, Syed Masood
supporting information, p. 358 - 361 (2022/01/20)
Herein, we report two methods for the synthesis of the osteoarthritis drug rhein and its prodrug diacerein using a chemoenzymatic approach. The strategy relies on the use of an NADPH-dependent anthrol reductase of Talaromyces islandicus (ARti-2), which mediates the regioselective and reductive deoxygenation of anthraquinones. The work further implies similar biosynthesis of rhein in fungi.
Industrial production method suitable for diacerein
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Paragraph 0035-0037; 0046-0048; 0057-0059; 0068; 0069; 0070, (2018/07/30)
The invention discloses an industrial production method suitable for diacerein. A compound as shown in a formula I is obtained after carrying out secondary oxidation on raw materials. The industrial production disclosed by the invention overcomes the disadvantages of excessive heavy metal, serious pollution, and inflammability and explosibility of a finished product prepared through a synthesis route reported in existing literatures; a reagent used by the industrial production method is low in cost, environment pollution is small, the operation is easy, and the industrial production method issuitable for industrial production; a product is good in quality, total impurities are less, the content of single impurity is controlled to be 0.1 percent or less, the finished product is controlledto be in a single and stable crystal form, and the requirements of medicinal-class bulk drugs can be met.
