Bis l,2,3-triazol-2-yl stilbenes

3-triazol-2-yl)stilbene brighteners have high efficiencies and good lightfastness and are very resistant to chemical bleaches. They are employed as brighteners for cotton and polyamides. An example is 4,4 -bis(4-phenyl-l,2,3-triazol-2-yl)stilbcnc-2,2 -disulfonic acid dipotassium salt (32) [52237-03-3] [59], 

Compound 34 is obtained by bishydrazone formation from hydroxyiminoace-tophenone (33) and 4,4 -dihydrazinostilbene-2,2 -disulfonic acid followed by cyclization with urea [60], 

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