Procaine is a local anesthetic. Its hydrochloride is commonly used in clinic, and it is also known as novocaine. It is white crystalline or crystalline powder, and it is soluble in water. It is less toxic than cocaine. The addition of a trace of adrenaline into the injection can prolong the action time. It is used for infiltration anesthesia, spinal anesthesia, “closed therapy”, etc. In addition to the reactions of central nervous system and cardiovascular system caused by overdose, there are occasional allergic reactions. Skin allergy test shall be carried out before medication. Its metabolite p-aminobenzoic acid (PABA) can weaken the antibacterial efficacy of sulfonamides.
Procaine Basic Info
Infiltration anesthesia, spinal anesthesia, “closed therapy”
Athletes shall use it with caution
It can cause uneasiness, floating feeling and abnormal feeling around the mouth
White crystalline or crystalline powder
It has less toxicity and it is a commonly used local anesthetics
Western medicine, injection, drug, anesthetic
Chinese Name: procaine
Chinese Alias: procaine hydrochloride; novocaine; 4-amino-, 2-(diethylamino)ethyl ester; 4-aminobenzoic acid 2-diethylaminoethyl ester; novocaine; procaine
English Name: procaine
English alias: Benzoic acid, 4-amino-, 2-(diethylamino)ethyl ester; 4-aminobenzoic acid 2-diethylaminoethyl ester; PROCAINE; novocaine
CAS No: 59-46-1
Molecular Formula: C13H20N2O2
Molecular Mass: 236.31000
Precise Mass: 236.15200
Melting point: 61ºC
Boiling point: 373.6ºC at 760 mmHg
Refraction index: 1.542
Customs code: 2922499100
Dangerous goods transportation Code: UN 3249
Character: its hydrochloride is colorless, odorless, small needle-shaped or lobular crystal, slightly bitter, and dull to the tongue. It is easily soluble in water, slightly soluble in ethanol and slightly soluble in trichloromethane. Its aqueous solution is unstable, and it is easy to deteriorate in case of light or acid-base substances.
1. it is mainly used for infiltration anesthesia.
2. It is used for the operation of lower abdomen which does not take long. It can also be used for local intravenous anesthesia of limbs.
3. It is used for “closed therapy” to treat some injuries and inflammation, which can alleviate the symptoms of injury and inflammation to a certain extent.
4. It is used to correct vasomotor dysfunction of limbs.
5. Treat neurosis.
Method 1: the technical scheme of the preparation method of procaine includes the following steps:
(a) Weigh the nickel aluminum alloy, add it into the NaOH solution with the temperature of 55 ~ 65 ℃ and the concentration of 18 ~ 20% in batches within 1 ~ 1.5h, raise the temperature to 85 ~ 95 ℃ after feeding, and keep it for 2 ~ 3 hours before discharging, then place it still, pour out the solution, wash it with 70 ~ 80 ℃ water first, and then wash it with normal-temperature water to the pH value of 8 ~ 9, so as to obtain Raney nickel catalyst and store it with absolute ethanol;
(b) Nitrocaine is obtained by esterification of 4-nitrobenzoic acid and diethylaminoethanol in dimethylbenzene solvent;
(c) Nitrocaine is reduced in xylene solvent with Raney nickel as catalyst and hydrogen as reducing agent. The hydrogen pressure was 2.0 ~ 3.0MPa, the reaction temperature was 80 ~ 130 ℃, and the reaction time was 5 ~ 8 hours. Then, the material is cooled and discharged. After extraction and filtration, the pH value of the filtrate is adjusted, and the precipitation is filtered and dried to obtain solid procaine.
Method 2: the best synthetic method of procaine hydrochloride is:
60g of 4-nitrobenzoic acid, 360g of dimethylbenzene and 44g of diethylaminoethanol are added into a three-mouth bottle, heated and refluxed for water separation, and the reaction temperature is 141 ~ 143 ℃ for 12 hours; after the reaction, cool it to below 20 ℃ and recover dimethylbenzene under reduced pressure;
After recovery, cool it to below 40 ℃, slowly add 570g 6% dilute hydrochloric acid, stir it for 30 minutes, cool it to 20 ~ 25 ℃ and filter it to obtain the filtrate;
Add the filtrate from the previous step into the hydrogenation reactor, add 15g of catalyst Ni powder, purge it twice with nitrogen, inject hydrogen at 10 standard atmospheric pressure, control the reaction temperature at 50 ~ 60 ℃ for hydrogenation reaction, filter it after the reaction, add 16g refined salt into the filtrate, stir and dissolve it, and cool it to 10 ℃, then the product will be obtained.