The fungicidal activity of substituted 1,4‐naphthoquinones. Part III: Amino, anilino and acylamino derivatives

A variety of 2‐amino‐, 2‐anilino‐ and 2‐acylamino‐1, 4‐naphthoquinones, with hydrogen, chlorine, alkoxy, phenoxy, methylthio or phenylthio as the 3‐substituent, have been synthesised and assayed against Botrytis cinerea, Cladosporium fulvum and Venturia inaequalis. With few exceptions, only the 2‐acylamino compounds possessed appreciable fungicidal activity: this was of a high order in the cases of 2‐prop‐ionamido‐, 2‐N‐methylacetamido‐3‐methylthio‐, and 3‐methoxy‐2‐N‐methylacetamido‐1, 4‐naphthoquinones.