Preparation method of dibucaine hydrochloride

Abstract

A preparation method of dibucaine hydrochloride comprises the following steps: (a) adding 2-hydroxy-4-quinolinecarboxylic acid and toluene into a reactor, adding dropwise thionyl chloride, after completion of the reaction, directly removing the thionyl chloride by rotary evaporation, then directly adding dropwise N,N-diethylethanamine, stirring at 20-75 DEG C for 1-24h, filtering, washing with water and drying to obtain 2-chloro-N-[2-(Diethylamino) ethyl]-4-quinolinecarboxamide; (b) adding the 2-chloro-N-[2-(Diethylamino) ethyl]-4-quinolinecarboxamide to n-butanol and sodium n-butoxide, heating and stirring at reflux, and after completion of the reaction, adding the toluene for extraction and crystallization to obtain a dibucaine hydrochloride refined product; and (c) adding the dibucainehydrochloride refined product into a solvent, dropwise adding hydrochloric acid ethanol for solid precipitation, stirring for 2h, filtering and drying to obtain the dibucaine hydrochloride. The methodhas the advantages of cheap sources of raw materials, easy process operation control, high yield and stable quality, and is suitable for industrialized production.

Description

technical field [0001] The invention belongs to the field of pharmaceutical preparations. Specifically, the present invention relates to a kind of preparation method of dibucaine hydrochloride. Background technique [0002] Dibucaine hydrochloride is also known as cocaine, dibucaine, neobucaine, savcaine, and dibucaine hydrochloride. Although there are amides in its chemical structure, it is still the same as ester local anesthetics, and it can be hydrolyzed by plasma cholinesterase , clinically and can be used to identify the effect of the esterase. The efficacy of local anesthesia is 22-25 times greater than that of procaine, and the duration is longer, but the toxicity is 15-20 times greater than that of procaine. Once poisoning occurs, rescue needs It can be reversed after 4-8 hours. It is far more stable than procaine in the tissue, so the anesthesia lasts longer (about 3 times that of procaine). It is suitable for epidural anesthesia and spinal anesthesia, and is easy...

AI Technical Summary

Problems solved by technology

[0002] Dibucaine hydrochloride is also known as cocaine, dibucaine, neobucaine, savcaine, and dibucaine hydrochloride. Although there are amides in the chemical structure, it is still the same as ester local anesthetics, and can be hydrolyzed by plasma cholinesterase , clinically and can be used to identify the effect of the esterase. The efficacy of local anesthesia is 22-25 times greater than that of procaine, and the duration is longer, but the toxicity is 15-20 times greater than that of procaine. Once poisoning occurs, rescue needs It can be reversed after 4-8 hours. It is far more stable than procaine in the tissue, so the anesthesia lasts longer (about 3 times that of procaine). It is suitable for epidural anesthesia and spinal anesthesia, and is easy to pass Mucous membranes, also used for topical anesthesia, but less used for infiltration anesthesia due to its high toxicity (about 15 times higher than procaine)