Patent ID: 8115023

Claim:
A compound selected from a group consisting of: wherein: A is hydroxy, alkoxy, aryloxy, amino, alkylamino, dialkylamino or —OM, where M is a cation selected from the group consisting of ammonium, tetra-alkyl ammonium, and the cations of sodium, potassium, magnesium and zinc; W is hydrogen, alkyl, alkenyl, alkynyl, aryl, heteroaryl, halo, hydroxy, alkoxy, aryloxy, carboxy, amino, alkylamino, dialkylamino, acylamino, carboxamido, or sulfonamide; R a -R c are independently selected from a group costing of hydrogen, alkyl, aryl, acyl or alkoxyacyl; the integer n is zero, one or two; the integer m is one or two.