Abstract
1) Following the irradiation of ultraviolet light, an squeous solution of sulfanilamide elicits purple, accompanied by changes of maximal absorption spectrum from 260mu to 560mu in wavelength.
2) No spot is found with the paperchromatography of the concentrated purple solution in n-butanol-acetic asid-water system (4:1:2), while a purple spot at the original point in a water-saturated n-butanol. It is negative in Bratton-Marshall color reaction.
3) These changes are not observed in the other sulfa drugs than sulfanilamide. The purple substance is distinguished from p-hydroxylaminobenzene sulfonamide, a photoxidation product of sulfanilamide, in physicochemical characteristics.
