Synthesis and fungicidal activity of N‐(p‐sulfonylphenyl)‐N1 ‐carbamoylureas

A series of 11 N-(p-sulfonylphenyl)-N 1 -carbamoylureas was prepared by reaction of 1,6-diphenyl-2,4-dioxohexahydro-s-triazine with chlorosulfonic acid and thionyl chloride. The resultant N-(p-chlorosulfonylphenyl)-N 1 -carbamoylurea was subsequently condensed with amines, butanol, hydrazine and sodium azide. The hydrazide was reacted with carbonyl compounds and the azide with trimethyl phosphite. The products were tested for in-vivo fungicidal activity against barley powdery mildew (Erysiphe graminis); the acetone hydrazone derivative showed the highest activity.