Dipyridamole
;)
Ethanol,2,2¢,2¢¢,2¢¢¢-[4,8-di-1-piperidinylpyrimido[5,4-d]pyrimidine-2,6-diyl)dinitrilo]tetrakis-.
2,2¢,2¢¢,2¢¢¢-[4,8-Dipiperidinopyrimido[5,4-d]pyrimidine-2,6-diyl)dinitrilo]tetraethanol [58-32-2].
»Dipyridamole contains not less than 98.0percent and not more than 102.0percent of C24H40N8O4,calculated on the dried basis.
Packaging and storage—
Preserve in tight,light-resistant containers.Store at room temperature.
Identification,Infrared Absorption á197Kñ.
Melting range á741ñ:
between 162
and 168,but the range between beginning and end of melting does not exceed 2.
and 168,but the range between beginning and end of melting does not exceed 2.
Loss on drying á731ñ—
Dry it at 105for 3hours:it loses not more than 0.2%of its weight.
for 3hours:it loses not more than 0.2%of its weight.
Chloride—
Dissolve 500mg in 5mLof alcohol and 2mLof 2Nnitric acid,and add 1mLof silver nitrate TS:no turbidity or precipitate is produced.
Residue on ignition á281ñ:
not more than 0.1%.
Heavy metals,Method IIá231ñ:
0.001%.
Organic volatile impurities,Method IVá467ñ:
meets the requirements.
Chromatographic purity—
Test preparation A—
Prepare a solution of Dipyridamole in methanol having a known concentration of 1mg per mL.
Test preparation B—
Dilute 1.0mLof Test preparation Awith methanol to 100mL,and mix.
Procedure—
Inject 10µLof Test preparation Binto the chromatograph by means of a sampling valve,adjusting the operating parameters so that the response of the main peak (retention time about 6.5minutes)obtained is about 5%full scale.Inject 10µLof Test preparation A,and run the chromatograph for 10minutes:the sum of responses of all secondary peaks obtained from Test preparation Ais not greater than the response of the main peak obtained from Test preparation B(1.0%).
Assay—
Transfer about 450mg of Dipyridamole,accurately weighed,to a 250-mLbeaker,and dissolve in 50mLof glacial acetic acid.Stir for 30minutes.Add 75mLof acetone,and stir for an additional 15minutes.Titrate with 0.1Nperchloric acid VS,determining the endpoint potentiometrically,using a glass electrode and a silver-silver chloride reference electrode system.Perform a blank titration,and make any necessary correction.Each mLof 0.1Nperchloric acid is equivalent to 50.46mg of C24H40N8O4.
Auxiliary Information—
Staff Liaison:Andrzej Wilk,Ph.D.,Senior Scientific Associate
Expert Committee:(PA5)Pharmaceutical Analysis 5
USP28–NF23Page 673
Pharmacopeial Forum:Volume No.29(5)Page 1467
Phone Number:1-301-816-8305