Fungicides which are sulfonamide derivatives are represented by the general formula;
wherein R' is lower alkyl, lower alkenyl, lower alkynyl or aryl of 6 to 10 carbon atoms optionally substituted by up to 3 halogen atoms; R2 is lower alkyl, lower alkenyl, lower alkynyl or aryl of 6 to 10 carbon atoms optionally substituted by up to 3 halogen atoms or up to 3 lower alkoxy groups; and R3 is alkyl of 1 to 3 carbon atoms substituted by 3 to 6 halogen atoms or trihalovinyl. The compounds are solids which unexpectedly have higher melting points and reduced solubilities which enhance their utility as fungicides.