The invention concerns novel compounds of the formula I STR1 wherein: X are selected from halogen, nitro, cyano, alkyl, substituted alkyl, hydroxy, alkoxy, substituted alkoxy, alkenyl, alkenyloxy, alkynyl, alkynyloxy, acyloxy, alkoxycarbonyl, alkylthio, alkylsulfinyl, alkylsulfonyl, sulfamoyl, substituted sulfamoyl, alkanoyloxy, benzyloxy, substituted benzyloxy, amino, substituted amino, and the groups formyl and alkanoyl and the oxime, imine and Schiff base derivatives thereof; R1 is selected from hydrogen, alkyl, alkenyl, alkynyl, substituted alkyl, alkylsulfonyl, arylsulfonyl, acyl and an inorganic or organic cation; R2 is selected from alkyl, substituted alkyl, alkenyl, haloalkenyl, alkynyl and haloalkynyl; R3 is selected from alkyl, fluoroalkyl, alkenyl, alkynyl, and phenyl; R4 is selected from hydrogen, halogen, alkyl, cyano and alkoxycarbonyl; and n is selected from the integers 1 and 2. The compounds of the invention show herbicidal properties and plant growth regulating properties and in further embodiments the invention provides processes for the preparation of compounds of formula I, intermediates useful in the preparation of the compounds of formula I, compositions containing as active ingredient a compound of formula I, and herbicidal and plant growth regulating processes utilizing compounds of formula I.