Ureides, bromine-containing

A more specific method of detecting barbituric acids is through the murexide reaction [86a, 173] and of thiobarbituric acids, through the iodine-azide reaction (Rgt. No. 142) [173]. Bromine-containing barbituric acids may be characterised by oxidation yielding bromine which then converts fluorescein into eosin (Rgt. No. 119). Larger amounts of barbituric acids and ureides, separated by TLC, can be removed from the layer by microsublimation and identified through their crystal form [8]. 

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