| abstract |
Abstract of the Disclosure: 1-Hydroxypyrazole deriva-tives of the formula (I) (I) where A is -SO-, -SO2- or -SO2-N-, n is 0 or 1, R1, R2 and R3 independently of one another are each hydrogen, chlorine, bromine or iodine, R4 is hydrogen, a straight-chain or branched, open-chain alkyl, alkenyl or alkynyl radical, a cyclic alkyl, alkenyl or alkynyl radical or aryl or aralkyl, and the radicals R4 which are capable of substitution may furthermore be mono-substituted or polysubstituted by halogen, haloalkyl, haloalkoxy, alkyl, alkoxy, alkoxycarbonyl, -OH, =0, -COOH or salts of this, -NO2 or -CN, have a nitrification-inhibiting action. Substances where R4 is not hydrogen when n is 0 are novel. |