Uracil-4-sulfonic acid, 5-amino

The 5,6-double bond in uracil, 5-fluorouracil, /V-alkyluracils, thiouracils, and uridines adds sodium sulfite or bisulfite to give the corresponding 5,6-dihydro-6-sulfonic acid salts. Bisulfite addition to cytosines and cytidine may be succeeded by a second reaction involving nucleophilic replacement of the amino group, for example, by water. 

Ultraviolet spectrometry, of sulfonic esters of carbohydrates, 257 Uracil, l-(5-amino-5-deoxy-/3-D-allofura-nosyluronic acid)-5-(hydroxymethyl)-, 116... 

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