Cinchocaine Base Powder CAS 73-78-9 - Local Anesthetic from Trusted China Suppliers and Factory

ChEBI: A monocarboxylic acid amide that is the 2-(diethylamino)ethyl amide of 2-butoxyquinoline-4-carboxylic acid. One of the most potent and toxic of the long-acting local anesthetics, its parenteral use was restricted to spinal anesthesia. It is now generally only used (usually as the hydrochloride) in creams and ointments and in suppositories for temporary relief of pain and itching associated with skin and anorectal conditions.

A benzene solution of 2.2 parts of α-chloro-γ-quinoline-carboxylic acid chloride is gradually mixed, while cooling, with 2.3 parts of unsymmetrical diethylethylenediamine. When the reaction is at an end the solution is washed with water and the new base extracted by means of hydrochloric acid. The base is precipitated by means of sodium carbonate and extracted with benzene. The solvent is distilled and the base recrystallized from petroleum ether. The α-chloro-γ-quinoline-carboxylic acid diethyl-amino-ethylene amide forms colorless lamina crystals of melting point 74°C. With acids the base forms neutral salts soluble in water.

A solution of 2.5 parts of sodium in n-butylalcohol is boiled with 30 parts of α- chloro-γ-quinoline-carboxylic acid diethyl-amino-ethylene-amide in a reflux apparatus, and when the reaction is over the excess of butylalcohol is distilled. The remaining base is taken up with ether; the solution is washed with water and dried. The solvent is then distilled. The α-n-butoxy-γ-quinoline. carboxylic acid diethyl-amino-ethylene-amide forms as colorless crystals, after recrystallization from petroleum ether melting point of it 64°C.

In practice it is usually used as hydrochloride.

Articaine has a secondary nitrogen with a pKa of 7.8. It contains an aromatic thiophene ring bioisostere of the phenyl ring found in most other amide anesthetics. The log P of a benzene ring is 2.13 and the thiophene ring log P is 1.81, thus the thiophene ring is more hydrophilic than a phenyl ring. Although the thiophene ring has less lipid solubility than a phenyl ring, articaine is a lipid-soluble compound due to the propylamine, the branched methyl and the substitutions on the thiophene ring. The onset of action of articaine is similar to lidocaine’s onset of action.

Articaine is available in a 4% solution with epinephrine for use in infiltration and nerve block anesthesia. Articaine is metabolized rapidly via plasma and tissue carboxyesterase to its primary metabolite, the inactive, water-soluble carboxylic acid. Approximately 40% to 70% of articaine administered epidurally is metabolized to the carboxylic acid, articainic acid. Approximately 4% to 15% of the articainic acid undergoes glucuronide conjugation and only 3% of the dose is recovered unchanged in the urine. The rapid plasma metabolism and reported inactivity of the carboxylic acid metabolite make articaine a potentially safer anesthetic agent when multiple or large doses are necessary.

Cinchocaine is a local anesthetic, used for Na+ channel blocker.