Ranitidine

(E )-form (upper) and (Z)- form ( see below)

  • C13H22N4O3S ( ranitidine )
  • C13H22N4O3S · HCl ( · ranitidine hydrochloride)
  • C19H30BiN4O10S ( ranitidine bismuth citrate · )
  • 66357-35-5 ( ranitidine )
  • 66357-59-3 ( · ranitidine hydrochloride)
  • 128345-62-0 ( ranitidine bismuth citrate · )

A02BA02

Ulkustherapeutika

H2 - antihistamine

  • 314.40 g · mol -1 ( ranitidine )
  • 350.86 g.mol -1 ( · ranitidine hydrochloride)
  • 715.51 g · mol -1 ( ranitidine bismuth citrate · )
  • 73.5 ° C ( ranitidine, polymorphic Form A)
  • 77.7 ° C ( ranitidine, polymorphic Form B )
  • 144.5 ° C ( ranitidine · hydrochloride polymorph A)
  • 146.2 ° C ( · ranitidine hydrochloride polymorphic form B)

Soluble in acetic acid and water, soluble in methanol ( · ranitidine hydrochloride)

Hydrochloride

884 mg · kg -1 ( LD50, mouse, oral)

Template: Infobox chemical / molecular formula search available

Ranitidine is a drug from the group of H2 antihistamines, which is used for control of gastric acid production in heartburn, for treatment of reflux disease and peptic ulcer prophylaxis both in human medicine and in veterinary medicine. In addition to prescription drugs, there are now ranitidine low doses also available over the counter at the pharmacy. However, the application should not be longer than seven days without medical care.

Production and representation

The synthesis of ranitidine is via the production of two key intermediates, the reaction leads to the target molecule. The synthesis of a precursor starts with the parallel alkylation and amination of furfuryl alcohol to 5 Dimethylaminomethylfurfurylalkohol, which is then reacted with cysteamine hydrochloride to Dimethylaminomethylfurfurylthioether.

Synthesis of the second precursor starts with the reaction of carbon disulfide and methylamine in benzene with sodium hydroxide solution in the presence of tetrabutylammonium bromide to dimethyl-N- methylcarboimidodithionat. The reaction with nitromethane then leads to the N-methyl- 1 -methylthio -2- nitroethenamin.

The target molecule is obtained by reacting the thioether with the Nitroethenamin.

Isomerism

Due to the interaction between the amine functions and of the nitro group with a six-membered ring, the rotational barrier of the carbon- carbon double bond is very low. In the NMR spectrum, only averaged signals ( E) - and (Z )-isomer found. The system can freeze at 271 K, then where separate signals for (E ) - and ( Z)- isomer was found. At room temperature, so are both isomers, the ranitidine at the same time before.

Effect

Ranitidine is a reversible, competitive antagonist of the histamine H2- receptor ( H2 antihistamine ). Through this receptor blockade histamine- dependent production of hydrochloric acid and digestive enzyme release of pepsin in the stomach is reduced. Ranitidine is about ten times stronger in this effect than cimetidine, but has significantly fewer side effects.

Ranitidine is rapidly absorbed in the intestine after oral ingestion. It is distributed in the body, passes through the placenta and is also excreted in the milk. Ranitidine is metabolized in the liver and excreted by the kidneys. The duration of action is about 8 to 12 hours.

Application

Ranitidine is used for ulcers and inflammation of the stomach, abomasum, duodenum (duodenum ), gastritis, esophagitis and gastroesophageal reflux disease. However, recent guidelines cause proton pump inhibitor H2 blockers in the treatment of gastritis, esophagitis and reflux disease before.

At the house dog ranitidine can also be used for the treatment of gastrinoma ( Zollinger -Ellison syndrome canine ), mastocytosis, and mast cell tumors.

Ranitidine is used for example, to the stomach protection during cortisone therapy and also sometimes referred to as gastric protection agents in pain therapy with nonsteroidal anti-inflammatory drugs, as these often, especially at high doses and / or long-term use, stomach pain, stomach bleeding and heartburn ( acid regurgitation ) lead.

Contraindications and side effects

The agent may not be used for a known incompatibility. In kidney dysfunction ranitidine should be used with caution.

Although almost all organs H2 receptors possess, the effects on other organs are barely detectable. Rare side effects in humans are mental confusion, headache, agranulocytosis, transient cardiac arrhythmias ( bradycardia ), rash, nausea with vomiting, diarrhea, constipation and loss of libido.

Ranitidine should not be taken with alcohol as ranitidine significantly increased, thus leading the bioavailability of ethanol in a significantly higher concentration of ethanol. This is due to the reduction in its first-pass extraction.

CAS registry number PubChem Anatomical Therapeutic Chemical Classification System DrugBank Active ingredient Tetra-n-butylammonium bromide Enamine Zollinger–Ellison syndrome Digital Object Identifier
457590
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