C75H70N6O6 1151.40

Quinolinium,6-(dimethylamino)-2-[2-(2,5-dimethyl-1-phenyl]-1H-pyrrol-[3-yl)ethenyl]-1-methyl-,salt with 4,4¢-methylenebis[3-hydroxy-[2-naphthalenecarboxylic acid](2:1).
6-(Dimethylamino)-2-[2-(2,5-dimethyl-1-phenylpyrrol-3-yl)vinyl]-1-methylquinolinium 4,4¢-methylenebis[3-hydroxy-2-naphthoate](2:1) [3546-41-6].

Packaging and storage— Preserve in tight,light-resistant containers.

USP Reference standards á11ñ— USP Pyrvinium Pamoate RS.

Identification—

Water,Method Iá921ñ: not more than 6.0%,a 200-mg specimen being used for the test,and a mixture of 10mLof methanol and 10mLof chloroform being used as the solvent.

Residue on ignition á281ñ: not more than 0.5%.

Assay— [NOTE—Use low-actinic flasks in preparing the solutions,and otherwise protect the solutions from unnecessary exposure to bright light.Complete the assay without prolonged interruption.]Dissolve about 250mg of Pyrvinium Pamoate,accurately weighed,in 125mLof glacial acetic acid in a 250-mLvolumetric flask,dilute with methanol to volume,and mix.Transfer 5mLof this solution to a 500-mLvolumetric flask,dilute with methanol to volume,and mix.Similarly dissolve an accurately weighed quantity of USP Pyrvinium Pamoate RSin glacial acetic acid,using 1mLfor each 2mg taken,and dilute quantitatively and stepwise with methanol to obtain a Standard solution having a known concentration of about 10µg per mL.Concomitantly determine the absorbances of both solutions in 1-cm cells at the wavelength of maximum absorbance at about 505nm,with a suitable spectrophotometer,using methanol as the blank.Calculate the quantity,in mg,of C75H70N6O6in the portion of Pyrvinium Pamoate taken by the formula: in which Cis the concentration,in µg per mL,of USP Pyrvinium Pamoate RSin the Standard solution,calculated on the anhydrous basis,and AUand ASare the absorbances of the solution of Pyrvinium Pamoate and the Standard solution,respectively.

Expert Committee:(PA7)Pharmaceutical Analysis 7

USP28–NF23Page 1687

Phone Number:1-301-816-8394