Fungicidal activity and chemical constitution. XVIII. The activity of 4-(1-cyclo-, 1-iso- and 1-n-propylalkyl)-2, 6-dinitrophenols against powdery mildews

The synthesis of seven 4-(1-cyclopropylalkyl)- and eight 4-(1-isopropylalkyl)-2, 6-dinitrophenols is described. When tested, together with six 4-(1-n-propylalkyl)-2, 6-dinitrophenols, several of these compounds showed high protectant activities against apple and cucumber powdery mildews. Their activities are discussed in relation to π values obtained from g.l.c. retention times, and to hydrogen bonding characteristics (both intra-and inter-) derived from infrared spectroscopic data.