Sulfisoxazole
;)
Benzenesulfonamide,4-amino-N-(3,4-dimethyl-5-isoxazolyl)-.
N1-(3,4-Dimethyl-5-isoxazolyl)sulfanilamide [127-69-5].
»Sulfisoxazole contains not less than 99.0percent and not more than 101.0percent of C11H13N3O3S,calculated on the dried basis.
Packaging and storage—
Preserve in tight,light-resistant containers.
Identification—
A:
Infrared Absorption á197Kñ.
B:
The UVabsorption spectrum of a 1in 100,000solution in pH7.5phosphate buffer (see Buffer Solutionsin the section Reagents,Indicators,and Solutions),prepared by dissolving about 100mg of Sulfisoxazole,accurately weighed,in 10mLof sodium hydroxide solution (1in 250)and adding sufficient amounts of the buffer solution to make 100mL,then diluting 10mLof the resulting solution with the buffer solution to 1000mL,exhibits maxima and minima at the same wavelengths as that of a similar solution of USP Sulfisoxazole RS,concomitantly measured.
C:
Dissolve about 10mg in 2mLof 3Nhydrochloric acid with the aid of heat,cool for 5minutes in an ice bath,add 3drops of sodium nitrite solution (1in 100),and dilute with water to 4mL:a yellow solution is produced.Add 1mLof sodium hydroxide solution (1in 10)containing 10mg of 2-naphthol:an orange-red precipitate is formed.
Loss on drying á731ñ—
Dry it at 105
for 2hours:it loses not more than 0.5%of its weight.
for 2hours:it loses not more than 0.5%of its weight.
Residue on ignition á281ñ:
not more than 0.1%.
Selenium á291ñ:
0.003%,a 200-mg test specimen being used.
Heavy metals,Method IIá231ñ:
0.002%.
Ordinary impurities á466ñ—
Test solution:
ethyl acetate.
Standard solution:
ethyl acetate.
Eluant:
a mixture of acetone,cyclohexane,and glacial acetic acid (5:4:1).
Visualization:
1.
Assay—
Place about 800mg of Sulfisoxazole,accurately weighed,in a 250-mLconical flask,add 50mLof dimethylformamide,shake thoroughly to dissolve the solid,add 5drops of a 1in 100solution of thymol blue in dimethylformamide,and titrate with 0.1Nlithium methoxide VSto a blue endpoint,taking precautions against absorption of atmospheric carbon dioxide.Perform a blank determination,and make any necessary correction.Each mLof 0.1Nlithium methoxide is equivalent to 26.73mg of C11H13N3O3S.
Auxiliary Information—
Staff Liaison:Behnam Davani,Ph.D.,MBA,Senior Scientist
Expert Committee:(PA7)Pharmaceutical Analysis 7
USP28–NF23Page 1836
Pharmacopeial Forum:Volume No.30(4)Page 1301
Phone Number:1-301-816-8394