PURPOSE: To obtain new fluorone and pyronin Y derivatives having an advantage of absorbing light at high wavelength which are useful as fluorescers and as photoinitiators, in particular as fluorescers and fluorescein dyestuffs in immunoanalysis.
CONSTITUTION: Compounds of formula I [A is H, alkyl, alkenyl, alkynyl, dichlorotriazinylamino or an electron withdrawing group having a stronger electron withdrawing group than phenyl or substd. phenyl; W and W' are each O, O-, NR2+ or NR2 (R is H, alkyl, aralykyl or aryl); Z is H or a counter ion), such as 2,4,5,7-tetraiodo-3-hydroxy-6-fluorone of the formula II are provided. Exemplary compounds of formulae I and II are obtained by reacting 3,6- dihydroxyxanthane of formula V with iodic acid in a soln. of anhydrous ethanol, in which the compd. of formula V is obtained from a compd. of formula III via a compd. of formula IV.
JIAMIN SHI
