Дикумарол

Описание

The plants containing dicoumarol mainly include red carnation grass (Trifolium pratense L., hongchezhoucao), rotten alfalfa (Medicago sativa L., zimuxu), rotten white vanilla rhinoceros (Melilotus albus Desr., baixiangcaomuxi), and other plants in Leguminosae.

Химические свойства

white fine crystalline powder

Физические свойства

Appearance: white or milky white crystalline powder, slightly fragran; Solubility: not dissolved in water, ethanol, and ether, slightly dissolved in chloroform, dissolved in alkali solution; Melting point: 287–293?°C.?It can be bluer or with purple fluorescence in the ultraviolet light.

История

In 1940, Karl Paul Link, a fertile scientist from the University of Wisconsin in the United States, first isolated the anticoagulant substance from the moldy alfalfa (Melilotus) and determined its structure. It is a kind of dicoumaroloid substance, combined by two molecules of coumarin substances. Since this material was found in the first few years, it has been used as a rodenticide .
In 1979, Conrad et?al. reacted p-nitrobenzene ketone with 4-hydroxycoumarin to obtain vinegar coumarin, which is basically the same as warfarin in anticoagulant, but its metabolites also have anticoagulant effect, so the duration of anticoagulation is longer than warfarin.

Использование

Dicumarol is a natural chemical used as an anticoagulant agents that functions as a vitamin K antagonist and is also a derivative of Coumarin.

Показания

Intravascular thromboembolic diseases include postoperative or postoperative thrombotic phlebitis, pulmonary embolism, myocardial infarction, and atrial fibrillation caused by embolism.

Определение

ChEBI: A hydroxycoumarin that is methane in which two hydrogens have each been substituted by a 4-hydroxycoumarin-3-yl group.

Общее описание

Dicumarol, 3,3＇-methylenebis[4-hydroxycoumarin],is a white or creamy white crystalline powderwith a faint, pleasant odor and a slightly bitter taste. It ispractically insoluble in water or alcohol, slightly soluble inchloroform, and dissolved readily by solutions of fixed alkalies.The effects after administration require 12 to 72 hours todevelop and persist for 24 to 96 hours after discontinuance.

Фармакокине?тика

Dicoumarol is not completely absorbed in the gastrointestinal tract, often is associated with gastrointestinal discomfort, and is very rarely used clinically. Today, the only coumarin used in the United States is warfarin, but phenprocoumon and acenocomumarol are used in Europe.

Фармаколо?гия

Dicoumarin is an oral anticoagulant drug and is invalid in?vitro . Dicoumarin is a coumarin derivative, and its common mechanism is to inhibit synthesis of the coagulation factor in the liver. The structure of dicoumarin is similar to that of vitamin K and is an antagonist or a competitive inhibitor of vitamin K.?It binds to the vitamin K epoxide reductase in the liver, inhibits the conversion of vitamin K from epoxide to hydroquinone, and inhibits the recycling of vitamin K, resulting in that the glutamate side chain of vitamin K-dependent coagulation factors II, VII, IX, and X cannot be carboxylated by γ-carboxy glutamate groups, affecting the binding of coagulation factor with calcium ion, and thereby inhibiting coagulation, reducing platelet adhesion, and prolonging thrombosis time . Dicoumarol drugs have no direct confrontation with synthesized prothrombin and coagulation factor, so it is ineffective in?vitro. After withdrawal of dicoumarin, prothrombin and coagulation factors II, IV, IX, and X gradually restore to a certain level, and hence the anticoagulant effect disappear, so its efficacy can be maintained for a long time .

Клиническое использование

Dicumarol is used alone or as an adjunct to heparin in theprophylaxis and treatment of intravascular clotting. It is usedin postoperative thrombophlebitis, pulmonary embolus, acuteembolic and thrombotic occlusion of peripheral arteries, andrecurrent idiopathic thrombophlebitis. It has no effect on analready-formed embolus but may prevent further intravascularclotting. Because the outcome of acute coronary thrombosisdepends largely on extension of the clot and formation ofmural thrombi in the heart chambers, with subsequent embolization,dicumarol has been used in this condition. It hasalso been administered to arrest impending gangrene afterfrostbite. The dose, after determination of the prothrombinclotting time, is 25 to 200 mg, depending on the size and thecondition of the patient. The drug is given orally in the formof capsules or tablets. On the second day and thereafter, itmay be given in amounts sufficient to maintain the prothrombinclotting time at about 30 seconds. If hemorrhages shouldoccur, a dosage of 50 to 100 mg of menadione sodium bisulfiteis injected, supplemented by a blood transfusion.

Побочные эффекты

The most serious adverse reaction of warfarin is bleeding, which can be against by vitamin K, and if necessary, fresh plasma or whole blood can be injected into the body to confront bleeding .