N-(1-arylpyrazol-4L)sulfonamides and their use as parasiticides

A method of treating a parasitic infestation or infection in a non-human animal or plant comprising administration of a therapeutically effective amount of a compound of Formula 1

• or a pharmaceutically, veterinarily, or agriculturally acceptable salt thereof, wherein
• R1 is phenyl optionally substituted by one or more groups independently selected from the group consisting of halo, cyano, hydroxy, C1-6 alkyl, C1-6 haloalkyl, C1-6, alkoxy, C1-6 haloalkoxy, C1-6 alkanoyl, C1-6 haloalkanoyl, —S(O)nC1-6alkyl, —S(O)nC1-6haloalkyl and pentafluorothio;
• R2 is cyano;
• R3 is C1-6 alkyl, C1-6 haloalkyl, or —(C0-3alkylene)-phenyl;
• R4 is hydrogen, C1-6 alkyl, C1-6haloalkyl, —(C0-3alkylene)-R7 or —(C1-3alkylene)-R8;
• or R3 and R4 taken together with the nitrogen and sulphur atoms to which they are attached form a 4 to 7-membered ring;
• R5 is hydrogen;
• R6 is C1-6 alkyl or haloalkyl;
• R7 is C3-8cycloalkyl, —S(O)nR9, phenyl, het, —CO2R6 or C(O)N(Ra)Rb;
• R8 is hydroxy, C1-6 alkoxy, C1-6 haloalkoxy, cyano, —N(Ra)Rb or —O—C(O)R6;
• R9 is C1-6 alkyl, C1-6 haloalkyl, C3-8cycloalkyl, —N(Ra)Rb, phenyl or het;
• Ra and Rb independently represent hydrogen, C1-6 alkyl, C1-6 haloalkyl, C2-6 alkenyl or C2-6 haloalkenyl, or Ra additionally is —(C0-3alkylene)-C3-8 cycloalkyl, —(C0-3alkylene)-phenyl or —(C0-3alkylene)-het, or together Ra and Rb form a 4- to 7-membered ring, optionally substituted by one or more groups independently selected from the group consisting of halo, hydroxy, C1-6 alkyl, C1-6haloalkyl, C1-6 alkoxy and C1-6haloalkoxy;
• n is the integer 0, 1 or 2;
• where het represents a four- to seven-membered heterocyclic group, which is aromatic or non-aromatic and which contains one or more heteroatoms selected from the group consisting of nitrogen, oxygen, sulfur and mixtures thereof;
• where both phenyl and het may be optionally substituted, where the valence allows, by one or more substituents independently selected from the group consisting of halo, hydroxy, cyano, nitro, C1-6 alkyl, C1-6haloalkyl, C1-6 alkenyl, C1-6haloalkenyl, C1-6alkoxy, C1-6haloalkoxy, C3-8 cycloalkyl, C1-6 alkanoyl, C1-6 haloalkanoyl, C1-6 alkylcarbonyloxy, C1-6 alkoxycarbonyl and NRaRb;
• where C3-8cycloalkyl may be optionally substituted by one or more groups independently selected from the group consisting of halo, C1-6alkyl, C1-6haloalkyl, C1-6alkenyl, C1-6haloalkenyl, hydroxy, C1-6alkoxy and C1-6haloalkoxy;
• and
• where any alkylene or alkenylene group may be optionally substituted by one or more halo.