Procaine base

There was added to 250 ml of a concentrated butyl acetate extract containing 74,000 units of the acid form of penicillin per ml, 50 ml of a butyl acetate solution containing 0.238 g per ml of procaine base. The solution was agitated for one hour. The precipitate which formed was very gummy and not in the form of discrete crystals. This precipitate was crystallized by scratching the side of the vessel and agitating further. After this treatment 18.25 g of crystalline procaine penicillin was obtained which assayed 1010 units per mg representing a yield of 99.6% of the activity contained in the concentrated extract. 

The potentiometric method has been used for the determination of pure procaine base or its hydrochloride salt, and for procaine in pharmaceutical formulations. Lemahieu and Resibois reported the potentiometric determination of procaine hydrochloride with silver nitrate in dimethyl sulfoxide [64], Procaine was potentiometrically analyzed using a procaine-selective membrane electrode [65]. Abou-Ouf et al. have used potentiometry to determine procaine and other drugs in ointments and creams with dibromohydantoins [66]. 

The addition of sodium bicarbonate increases the potency of the local anesthetics two to four times for direct application or injection into nerve tranks and probably for subdural injection and on application to mucous surfaces. This is due to the easier penetration of the free anesthetic bases, as compared with their salts. For these purposes, the usual solutions of the anesthetic salts may be mixed with an equal volume of 0.5% sodium bicarbonate solution, without loss of efficiency, and with a saving of one half of the anesthetic, and correspondingly smaller danger of accidents. The mixtures, however, do not keep well, and must be made just before use. Alkalinization or buffering has no advantage for hypodermic or intradermic injections, because these do not require much penetration. Procaine base dissolved by the aid of carbon dioxide is also more potent than the hydrochloride when applied to the cornea, but not for intramuscular injection. 

Strong bases (amphetamines, methamphetamine, procaine), bases of medium strength (cocaine, heroin, noscapine, quinine), weak bases (diazepam, methaqualone), strong acids (A-9-tetrahydrocannabinolic acid), moderately strong acids (phenobarbi-tal) and weak acids (A-9-tetrahydrocannabinol) can be separated in a single run along with neutral solutes (testosterone, testosterone propionate). However, in order to... 

Procaine base may be prepared by the interaction of 2-chloro ethyl-p-amino benzoate anc diethylamine at an elevated temperature under pressure. The base is eonverted into its hydrochloride subsequently. 

The procaine base is obtained by the dehydration of molecule of p-amino benzoic acid and 2-hydroxy triethyl amine, which on treatment with hydrochloric acid yields the official compound. Method-Ill From Ethylene Chlorohydrin ... 

Procaine Benzylpenicillin, C 6Hi804N 2S,Ci3H o02N2,H20, Mol. Wt. 588-7. This salt is composed of one molecule of procaine base and one molecule of benzylpenicillin with one molecule of water of crystallisation. The assay of procaine presents no serious difficulties. Although nitrite titration has been recommended the simplest method is titration with standard acid after alkaline chloroform extraction. 

Transfer about 01 g, accurately weighed, to a separator, add 20 ml of water and 5 ml of 10 per cent sodium carbonate decahydrate solution. Extract by shaking with successive quantities, each of 25 ml, of chloroform until complete extraction of the procaine is effected, washing each chloroform extract with the same 5 ml of water. Transfer the mixed chloroform extracts to a second separator, add 20 ml of 0 01 N sulphuric acid, shake thoroughly, allow to separate, run off the chloroform layer into a third separator and w ash with 5 ml of water. Titrate the excess of sulphuric acid in the aqueous solution and washings with O OIN sodium hydroxide using methyl red as indicator. 1 ml 0 01 N sulphuric acid == 0 002363 g of procaine base, C13H20O2N2. 

To 10 ml of the partially decomposed solution in a separator add 0 5 g of sodium carbonate and remove undecomposed procaine base and di-ethylaminoethanol by shaking three times with 20-ml portions of a mixture of 1 volume of wopropyl alcohol and 3 volumes of chloroform. Wash the mixed solvent with 5 ml of water in a second separator. Add the water to the first separator, after washing with a fresh quantity of 5 ml of mixed solvent. 

Transfer a measured quantity of the injection, or an aqueous solution of the tablets, expected to contain between 0 02 and 0 10 mg of procaine base, into a 10-ml stoppered measuring cylinder and, if necessary, dilute with water to 5 ml. Add 1 ml of N hydrochloric acid and 0 5 ml of a freshly-prepared 1 per cent aqueous solution of sodium nitrite, mix, and allow to stand for thirty seconds. Add 1 ml of a 15 per cent aqueous solution of ammonium sulphamate, shake vigorously, allow to stand for thirty seconds, add 1 ml of a freshly-prepared 1 per cent solution of the refined acid sodium salt of l-amino-8-naphthol-3,6-disulphonic acid in 20 per cent w/v aqueous sodium hydroxide, mix and dilute to 10 ml with water. 

Measure the extinction of the solution at 520 vcifA by means of a suitable absorptiometer and read the number of milligrams of procaine equivalent to the observed extinction from a calibration graph prepared by treating amounts of standard procaine solution in 0 1 N hydrochloric acid, covering the range 0 02 to 0 10 mg, in the same way. Procaine base X 1 155 = procaine hydrochloride. 

Procaine, etc. (amino-linked) Dopamine (Schiff s base) Sulfadiazine (Schiff s base)... 

In this chapter, the voltammetric study of local anesthetics (procaine and related compounds) [14—16], antihistamines (doxylamine and related compounds) [17,22], and uncouplers (2,4-dinitrophenol and related compounds) [18] at nitrobenzene (NB]Uwater (W) and 1,2-dichloroethane (DCE)-water (W) interfaces is discussed. Potential step voltammetry (chronoamperometry) or normal pulse voltammetry (NPV) and potential sweep voltammetry or cyclic voltammetry (CV) have been employed. Theoretical equations of the half-wave potential vs. pH diagram are derived and applied to interpret the midpoint potential or half-wave potential vs. pH plots to evaluate physicochemical properties, including the partition coefficients and dissociation constants of the drugs. Voltammetric study of the kinetics of protonation of base (procaine) in aqueous solution is also discussed. Finally, application to structure-activity relationship and mode of action study will be discussed briefly. 

The mass of procaine hydrochloride spectrum was obtained utilizing a Shimadzu model PQ-5000 mass spectrometer, with helium being used as the carrier gas. As shown in Figure 10, the mass spectrum shows a base peak at m/z = 86. The proposed fragmentation pattern of procaine hydrochloride is fully outlined in Table 5. 

The direct potentiometric determination (using a cation-selective membrane electrode) of procaine and some physiologically active amines in pharmaceuticals has been reported [70]. The sensing membrane was formed from PVC plasticized with dibutyl phthalate, and contained 0.1 mM trioctyloxybenzene-sulfonic acid in dibutyl phthalate. The reference solution was a mixture of 1 mM solution of the organic base and hydrochloric acid. Response was found to be linear over a wide concentration range, and the method was highly selective. 

A poly (vinylchloride) membrane electrode was described for local anesthetics, based on dibenzo-24-crown-8 as the electroactive material, and di(2-ethyl)hexyl phthalate as the plasticizer [74]. It was reported that the electrode exhibited a Nemstian response to procaine, and other electrode properties were also presented. The analysis was performed at pH 6 to 6.5 vs. S.C.E., with a 0.2 M lithium acetate agar bridge. Less efficient crown ethers studied at this time were benzo-15-crown-5, dibenzo-18-crown-6, and dibenzo-30-crown-10. 

Medvedovskii et al. have developed a method of alkalimetric two-phase titration for the determination of procaine hydrochloride and other organic base salts [83]. 

The method of Koval chuk et al. was applied in the determination of procaine [84], These authors have also developed another alkalimetric two-phase titration method for determination of the salts of organic bases, including procaine hydrochloride [85]. A solution of the base salt was mixed with 2 mL chloroform and 2 drops of 0.15% methylene blue solution, and the mixture titrated with 0.02 to 0.1 M sodium hydroxide with shaking. At the endpoint, the chloroform layer becomes pink-violet. 

Potentiometric non-aqueous titration (using bismuth oxyacetate and perchloric acid or trifluoromethylsulfonic acid) was used by Zakhari et al. (90) for the determination of procaine and other drugs (halides and nitrogen bases) [90], Procaine hydrochloride was dissolved in 5 1 acetic... 

Chen and Gao studied the use of oscillopolarographic titration, and reported a direct titration of the salts of weak organic bases (or acids) in aqueous solution [61]. In their work, they included the determination of procaine by an oscillopolarographic titration method. 

Assay methods for Procaine have been reported which make use either of its direct ultraviolet absorption, or which are based on colorimetric reactions of the drug entity. 

A colorimetric assay procedure for the quantitative analysis of procaine hydrochloride was developed by Tan and Shelton [38]. The method is based on the interaction of procaine with /i-dimethylamino-... 

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