Abstract: The invention concerns novel compounds of the formula I ##STR1## wherein: W are selected from alkyl, alkenyl and alkynyl;X are selected from halogen, nitro, cyano, alkyl, substituted alkyl, hydroxy, alkoxy, substituted alkoxy, alkenyl, alkynyl, alkenyloxy, alkynyloxy, acyloxy, alkoxycarbonyl, alkylthio, alkylsulfinyl, alkylsulfonyl, sulfamoyl, substituted sulfamoyl, amino, substituted amino, and the groups formyl and alkanoyl and the oxime, imine and Schiff base derivatives thereof, and an alkylene group which bridges two adjacent carbon atoms of the benzene ring;R.sup.1 is selected from hydrogen, alkyl, alkenyl, alkynyl, substituted alkyl, alkylsulfonyl, arylsulfonyl, acyl and an inorganic or organic cation;R.sup.2 is selected from alkyl, substituted alkyl, alkenyl, haloalkenyl, alkynyl and haloalkynyl;R.sup.