Herbicidal sulfonylureas, method of preparation and their use

Described are sulphonyl urea compounds of the general formula I in which R is a methyl or ethyl group; R is C1-C3 alkoxycarbonyl, a C1-C2 alkyl group with 1 to 5 fluorine atoms, methylsulphonyl, dimethylaminosulphonyl, thiomethyl, methylsulphoxide, methylsulphonyloxy, trifluoromethoxy, difluoromethoxy, difluorochloromethoxy, difluorochloromethyl or nitro; R is hydrogen, methyl, methoxy, ethoxy, fluorine, chlorine or thiomethyl; W is hydrogen or chlorine and Z is CH or N, plus salts of these compounds suitable for use in agriculture.