C19H22N2OS,C4H4O4 442.5 3598-37-6
Action and use
Dopamine receptor antagonist; neuroleptic.
Preparations
Acepromazine Injection
Acepromazine Tablets
DEFINITION
Acepromazine Maleate is 2-acetyl-10-(3-dimethylaminopropyl) phenothiazine hydrogen maleate.
It contains not less than 98.5% and not more than 101.0% of C19H22N2OS,C4H4O4 , calculated with reference to the dried substance.
CHARACTERISTICS
A yellow, crystalline powder.
Soluble in water; freely soluble in chloroform; soluble in ethanol (96%); slightly soluble in ether.
IDENTIFICATION
A. Dissolve 20 mg in 2 mL of water, add 3 mL of 2M sodium hydroxide, extract with 5 mL of cyclohexane and evaporate to dryness under reduced pressure. The infrared absorption
spectrum of the residue, Appendix II A, is concordant with the reference spectrum of acepromazine (RSV 01).
B. Complies with the test for identification of phenothiazines, Appendix III A, applying to the plate 1 μL of each solution and using acepromazine maleate BPCRS for the preparation of solution (2).
C. Dissolve 0.2 g in a mixture of 3 mL of water and 2 mL of 5M sodium hydroxide and shake with three 3-mL quantities of ether. Add to the aqueous solution 2 mL of bromine solution, warm in a water bath for 10 minutes, heat to boiling, cool and add 0.25 mL to a solution of 10 mg of resorcinol in 3 mL of sulfuric acid. A bluish black colour develops on heating for 15 minutes in a water bath.
TESTS
Acidity
pH of a 1.0% w/v solution, 4.0 to 4.5, Appendix V L.
Melting point
136° to 139°, Appendix V A.
Related substances
Complies with the test for related substances in phenothiazines, Appendix III A, but using a mixture of 75 volumes of n-hexane, 17 volumes of butan-2-one and 8 volumes of diethylamine as the mobile phase.
Loss on drying
When dried to constant weight at 105°, loses not more than 1.0% of its weight. Use 1 g.
Sulfated ash
Not more than 0.2%, Appendix IX A.
ASSAY
Dissolve 0.4 g in 50 mL of acetic anhydride and carry out Method I for non-aqueous titration, Appendix VIII A, using crystal violet solution as indicator. Each mL of 0.1M perchloric acid VS is equivalent to 44.25 mg of C19H22N2OS,C4H4O4
