C10H11I2NO3 447.01

1(4H)-Pyridineacetic acid,3,5-diiodo-4-oxo-,propyl ester.
Propyl 3,5-diiodo-4-oxo-1(4H)pyridineacetate [587-61-1].

Packaging and storage— Preserve in tight,light-resistant containers.Store at 25,excursions permitted between 15and 30.

Identification—

Melting range á741ñ: between 187and 190.

Acidity— Dissolve 1.0g in 40mLof hot n-propyl alcohol previously neutralized to phenolphthalein TS,cool,and allow to stand in an ice bath for 15minutes with frequent shaking.Filter,wash the residue with neutralized n-propyl alcohol,combine the filtrate and washings,add phenolphthalein TS,and titrate with 0.050Nsodium hydroxide to a pink color that persists for 15seconds:not more than 0.15mLof 0.050Nsodium hydroxide is required for neutralization.

Loss on drying á731ñ— Dry it at 105to constant weight:it loses not more than 0.5%of its weight.

Residue on ignition á281ñ: not more than 0.1%.

Iodine and iodide— Shake 2.4g with 30mLof water for 15minutes,filter,and to 10mLof filtrate add 1mLof 2Nnitric acid,1mLof sodium nitrite solution (1in 500),and 2mLof chloroform.Shake,and centrifuge:any purple color in the chloroform layer is not darker than that obtained with a mixture of 6mLof water and 4mLof potassium iodide solution (2.6in 100,000)treated in the same manner (0.01%of I).

Heavy metals,Method IIá231ñ: 0.002%.

Assay— Using about 15mg of Propyliodone,accurately weighed,proceed as directed in the Assayunder Iodoquinol.Each mLof 0.02Nsodium thiosulfate is equivalent to 0.7450mg of C10H11I2NO3.

Expert Committee:(RMI)Radiopharmaceuticals and Medical Imaging Agents

USP28–NF23Page 1666

Phone Number:1-301-816-8305